--- /dev/null
+/*
+ * Copyright (C) 2007 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/blkdev.h>
+#include <linux/scatterlist.h>
+#include <linux/swap.h>
+#include <linux/radix-tree.h>
+#include <linux/writeback.h>
+#include <linux/buffer_head.h>
+#include <linux/workqueue.h>
+#include <linux/kthread.h>
+#include <linux/freezer.h>
+#include <linux/slab.h>
+#include <linux/migrate.h>
+#include <linux/ratelimit.h>
+#include <linux/uuid.h>
+#include <linux/semaphore.h>
+#include <asm/unaligned.h>
+#include "ctree.h"
+#include "disk-io.h"
+#include "hash.h"
+#include "transaction.h"
+#include "btrfs_inode.h"
+#include "volumes.h"
+#include "print-tree.h"
+#include "locking.h"
+#include "tree-log.h"
+#include "free-space-cache.h"
+#include "inode-map.h"
+#include "check-integrity.h"
+#include "rcu-string.h"
+#include "dev-replace.h"
+#include "raid56.h"
+#include "sysfs.h"
+#include "qgroup.h"
+
+#ifdef CONFIG_X86
+#include <asm/cpufeature.h>
+#endif
+
+static const struct extent_io_ops btree_extent_io_ops;
+static void end_workqueue_fn(struct btrfs_work *work);
+static void free_fs_root(struct btrfs_root *root);
+static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
+ int read_only);
+static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
+static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
+ struct btrfs_root *root);
+static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
+static int btrfs_destroy_marked_extents(struct btrfs_root *root,
+ struct extent_io_tree *dirty_pages,
+ int mark);
+static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
+ struct extent_io_tree *pinned_extents);
+static int btrfs_cleanup_transaction(struct btrfs_root *root);
+static void btrfs_error_commit_super(struct btrfs_root *root);
+
+/*
+ * btrfs_end_io_wq structs are used to do processing in task context when an IO
+ * is complete. This is used during reads to verify checksums, and it is used
+ * by writes to insert metadata for new file extents after IO is complete.
+ */
+struct btrfs_end_io_wq {
+ struct bio *bio;
+ bio_end_io_t *end_io;
+ void *private;
+ struct btrfs_fs_info *info;
+ int error;
+ enum btrfs_wq_endio_type metadata;
+ struct list_head list;
+ struct btrfs_work work;
+};
+
+static struct kmem_cache *btrfs_end_io_wq_cache;
+
+int __init btrfs_end_io_wq_init(void)
+{
+ btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq",
+ sizeof(struct btrfs_end_io_wq),
+ 0,
+ SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+ NULL);
+ if (!btrfs_end_io_wq_cache)
+ return -ENOMEM;
+ return 0;
+}
+
+void btrfs_end_io_wq_exit(void)
+{
+ if (btrfs_end_io_wq_cache)
+ kmem_cache_destroy(btrfs_end_io_wq_cache);
+}
+
+/*
+ * async submit bios are used to offload expensive checksumming
+ * onto the worker threads. They checksum file and metadata bios
+ * just before they are sent down the IO stack.
+ */
+struct async_submit_bio {
+ struct inode *inode;
+ struct bio *bio;
+ struct list_head list;
+ extent_submit_bio_hook_t *submit_bio_start;
+ extent_submit_bio_hook_t *submit_bio_done;
+ int rw;
+ int mirror_num;
+ unsigned long bio_flags;
+ /*
+ * bio_offset is optional, can be used if the pages in the bio
+ * can't tell us where in the file the bio should go
+ */
+ u64 bio_offset;
+ struct btrfs_work work;
+ int error;
+};
+
+/*
+ * Lockdep class keys for extent_buffer->lock's in this root. For a given
+ * eb, the lockdep key is determined by the btrfs_root it belongs to and
+ * the level the eb occupies in the tree.
+ *
+ * Different roots are used for different purposes and may nest inside each
+ * other and they require separate keysets. As lockdep keys should be
+ * static, assign keysets according to the purpose of the root as indicated
+ * by btrfs_root->objectid. This ensures that all special purpose roots
+ * have separate keysets.
+ *
+ * Lock-nesting across peer nodes is always done with the immediate parent
+ * node locked thus preventing deadlock. As lockdep doesn't know this, use
+ * subclass to avoid triggering lockdep warning in such cases.
+ *
+ * The key is set by the readpage_end_io_hook after the buffer has passed
+ * csum validation but before the pages are unlocked. It is also set by
+ * btrfs_init_new_buffer on freshly allocated blocks.
+ *
+ * We also add a check to make sure the highest level of the tree is the
+ * same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this code
+ * needs update as well.
+ */
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# if BTRFS_MAX_LEVEL != 8
+# error
+# endif
+
+static struct btrfs_lockdep_keyset {
+ u64 id; /* root objectid */
+ const char *name_stem; /* lock name stem */
+ char names[BTRFS_MAX_LEVEL + 1][20];
+ struct lock_class_key keys[BTRFS_MAX_LEVEL + 1];
+} btrfs_lockdep_keysets[] = {
+ { .id = BTRFS_ROOT_TREE_OBJECTID, .name_stem = "root" },
+ { .id = BTRFS_EXTENT_TREE_OBJECTID, .name_stem = "extent" },
+ { .id = BTRFS_CHUNK_TREE_OBJECTID, .name_stem = "chunk" },
+ { .id = BTRFS_DEV_TREE_OBJECTID, .name_stem = "dev" },
+ { .id = BTRFS_FS_TREE_OBJECTID, .name_stem = "fs" },
+ { .id = BTRFS_CSUM_TREE_OBJECTID, .name_stem = "csum" },
+ { .id = BTRFS_QUOTA_TREE_OBJECTID, .name_stem = "quota" },
+ { .id = BTRFS_TREE_LOG_OBJECTID, .name_stem = "log" },
+ { .id = BTRFS_TREE_RELOC_OBJECTID, .name_stem = "treloc" },
+ { .id = BTRFS_DATA_RELOC_TREE_OBJECTID, .name_stem = "dreloc" },
+ { .id = BTRFS_UUID_TREE_OBJECTID, .name_stem = "uuid" },
+ { .id = 0, .name_stem = "tree" },
+};
+
+void __init btrfs_init_lockdep(void)
+{
+ int i, j;
+
+ /* initialize lockdep class names */
+ for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
+ struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
+
+ for (j = 0; j < ARRAY_SIZE(ks->names); j++)
+ snprintf(ks->names[j], sizeof(ks->names[j]),
+ "btrfs-%s-%02d", ks->name_stem, j);
+ }
+}
+
+void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
+ int level)
+{
+ struct btrfs_lockdep_keyset *ks;
+
+ BUG_ON(level >= ARRAY_SIZE(ks->keys));
+
+ /* find the matching keyset, id 0 is the default entry */
+ for (ks = btrfs_lockdep_keysets; ks->id; ks++)
+ if (ks->id == objectid)
+ break;
+
+ lockdep_set_class_and_name(&eb->lock,
+ &ks->keys[level], ks->names[level]);
+}
+
+#endif
+
+/*
+ * extents on the btree inode are pretty simple, there's one extent
+ * that covers the entire device
+ */
+static struct extent_map *btree_get_extent(struct inode *inode,
+ struct page *page, size_t pg_offset, u64 start, u64 len,
+ int create)
+{
+ struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+ struct extent_map *em;
+ int ret;
+
+ read_lock(&em_tree->lock);
+ em = lookup_extent_mapping(em_tree, start, len);
+ if (em) {
+ em->bdev =
+ BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
+ read_unlock(&em_tree->lock);
+ goto out;
+ }
+ read_unlock(&em_tree->lock);
+
+ em = alloc_extent_map();
+ if (!em) {
+ em = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+ em->start = 0;
+ em->len = (u64)-1;
+ em->block_len = (u64)-1;
+ em->block_start = 0;
+ em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
+
+ write_lock(&em_tree->lock);
+ ret = add_extent_mapping(em_tree, em, 0);
+ if (ret == -EEXIST) {
+ free_extent_map(em);
+ em = lookup_extent_mapping(em_tree, start, len);
+ if (!em)
+ em = ERR_PTR(-EIO);
+ } else if (ret) {
+ free_extent_map(em);
+ em = ERR_PTR(ret);
+ }
+ write_unlock(&em_tree->lock);
+
+out:
+ return em;
+}
+
+u32 btrfs_csum_data(char *data, u32 seed, size_t len)
+{
+ return btrfs_crc32c(seed, data, len);
+}
+
+void btrfs_csum_final(u32 crc, char *result)
+{
+ put_unaligned_le32(~crc, result);
+}
+
+/*
+ * compute the csum for a btree block, and either verify it or write it
+ * into the csum field of the block.
+ */
+static int csum_tree_block(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *buf,
+ int verify)
+{
+ u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+ char *result = NULL;
+ unsigned long len;
+ unsigned long cur_len;
+ unsigned long offset = BTRFS_CSUM_SIZE;
+ char *kaddr;
+ unsigned long map_start;
+ unsigned long map_len;
+ int err;
+ u32 crc = ~(u32)0;
+ unsigned long inline_result;
+
+ len = buf->len - offset;
+ while (len > 0) {
+ err = map_private_extent_buffer(buf, offset, 32,
+ &kaddr, &map_start, &map_len);
+ if (err)
+ return 1;
+ cur_len = min(len, map_len - (offset - map_start));
+ crc = btrfs_csum_data(kaddr + offset - map_start,
+ crc, cur_len);
+ len -= cur_len;
+ offset += cur_len;
+ }
+ if (csum_size > sizeof(inline_result)) {
+ result = kzalloc(csum_size, GFP_NOFS);
+ if (!result)
+ return 1;
+ } else {
+ result = (char *)&inline_result;
+ }
+
+ btrfs_csum_final(crc, result);
+
+ if (verify) {
+ if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
+ u32 val;
+ u32 found = 0;
+ memcpy(&found, result, csum_size);
+
+ read_extent_buffer(buf, &val, 0, csum_size);
+ printk_ratelimited(KERN_WARNING
+ "BTRFS: %s checksum verify failed on %llu wanted %X found %X "
+ "level %d\n",
+ fs_info->sb->s_id, buf->start,
+ val, found, btrfs_header_level(buf));
+ if (result != (char *)&inline_result)
+ kfree(result);
+ return 1;
+ }
+ } else {
+ write_extent_buffer(buf, result, 0, csum_size);
+ }
+ if (result != (char *)&inline_result)
+ kfree(result);
+ return 0;
+}
+
+/*
+ * we can't consider a given block up to date unless the transid of the
+ * block matches the transid in the parent node's pointer. This is how we
+ * detect blocks that either didn't get written at all or got written
+ * in the wrong place.
+ */
+static int verify_parent_transid(struct extent_io_tree *io_tree,
+ struct extent_buffer *eb, u64 parent_transid,
+ int atomic)
+{
+ struct extent_state *cached_state = NULL;
+ int ret;
+ bool need_lock = (current->journal_info == BTRFS_SEND_TRANS_STUB);
+
+ if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
+ return 0;
+
+ if (atomic)
+ return -EAGAIN;
+
+ if (need_lock) {
+ btrfs_tree_read_lock(eb);
+ btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
+ }
+
+ lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
+ 0, &cached_state);
+ if (extent_buffer_uptodate(eb) &&
+ btrfs_header_generation(eb) == parent_transid) {
+ ret = 0;
+ goto out;
+ }
+ printk_ratelimited(KERN_ERR
+ "BTRFS (device %s): parent transid verify failed on %llu wanted %llu found %llu\n",
+ eb->fs_info->sb->s_id, eb->start,
+ parent_transid, btrfs_header_generation(eb));
+ ret = 1;
+
+ /*
+ * Things reading via commit roots that don't have normal protection,
+ * like send, can have a really old block in cache that may point at a
+ * block that has been free'd and re-allocated. So don't clear uptodate
+ * if we find an eb that is under IO (dirty/writeback) because we could
+ * end up reading in the stale data and then writing it back out and
+ * making everybody very sad.
+ */
+ if (!extent_buffer_under_io(eb))
+ clear_extent_buffer_uptodate(eb);
+out:
+ unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
+ &cached_state, GFP_NOFS);
+ if (need_lock)
+ btrfs_tree_read_unlock_blocking(eb);
+ return ret;
+}
+
+/*
+ * Return 0 if the superblock checksum type matches the checksum value of that
+ * algorithm. Pass the raw disk superblock data.
+ */
+static int btrfs_check_super_csum(char *raw_disk_sb)
+{
+ struct btrfs_super_block *disk_sb =
+ (struct btrfs_super_block *)raw_disk_sb;
+ u16 csum_type = btrfs_super_csum_type(disk_sb);
+ int ret = 0;
+
+ if (csum_type == BTRFS_CSUM_TYPE_CRC32) {
+ u32 crc = ~(u32)0;
+ const int csum_size = sizeof(crc);
+ char result[csum_size];
+
+ /*
+ * The super_block structure does not span the whole
+ * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space
+ * is filled with zeros and is included in the checkum.
+ */
+ crc = btrfs_csum_data(raw_disk_sb + BTRFS_CSUM_SIZE,
+ crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
+ btrfs_csum_final(crc, result);
+
+ if (memcmp(raw_disk_sb, result, csum_size))
+ ret = 1;
+ }
+
+ if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
+ printk(KERN_ERR "BTRFS: unsupported checksum algorithm %u\n",
+ csum_type);
+ ret = 1;
+ }
+
+ return ret;
+}
+
+/*
+ * helper to read a given tree block, doing retries as required when
+ * the checksums don't match and we have alternate mirrors to try.
+ */
+static int btree_read_extent_buffer_pages(struct btrfs_root *root,
+ struct extent_buffer *eb,
+ u64 start, u64 parent_transid)
+{
+ struct extent_io_tree *io_tree;
+ int failed = 0;
+ int ret;
+ int num_copies = 0;
+ int mirror_num = 0;
+ int failed_mirror = 0;
+
+ clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
+ io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
+ while (1) {
+ ret = read_extent_buffer_pages(io_tree, eb, start,
+ WAIT_COMPLETE,
+ btree_get_extent, mirror_num);
+ if (!ret) {
+ if (!verify_parent_transid(io_tree, eb,
+ parent_transid, 0))
+ break;
+ else
+ ret = -EIO;
+ }
+
+ /*
+ * This buffer's crc is fine, but its contents are corrupted, so
+ * there is no reason to read the other copies, they won't be
+ * any less wrong.
+ */
+ if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
+ break;
+
+ num_copies = btrfs_num_copies(root->fs_info,
+ eb->start, eb->len);
+ if (num_copies == 1)
+ break;
+
+ if (!failed_mirror) {
+ failed = 1;
+ failed_mirror = eb->read_mirror;
+ }
+
+ mirror_num++;
+ if (mirror_num == failed_mirror)
+ mirror_num++;
+
+ if (mirror_num > num_copies)
+ break;
+ }
+
+ if (failed && !ret && failed_mirror)
+ repair_eb_io_failure(root, eb, failed_mirror);
+
+ return ret;
+}
+
+/*
+ * checksum a dirty tree block before IO. This has extra checks to make sure
+ * we only fill in the checksum field in the first page of a multi-page block
+ */
+
+static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page)
+{
+ u64 start = page_offset(page);
+ u64 found_start;
+ struct extent_buffer *eb;
+
+ eb = (struct extent_buffer *)page->private;
+ if (page != eb->pages[0])
+ return 0;
+ found_start = btrfs_header_bytenr(eb);
+ if (WARN_ON(found_start != start || !PageUptodate(page)))
+ return 0;
+ csum_tree_block(fs_info, eb, 0);
+ return 0;
+}
+
+static int check_tree_block_fsid(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *eb)
+{
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ u8 fsid[BTRFS_UUID_SIZE];
+ int ret = 1;
+
+ read_extent_buffer(eb, fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE);
+ while (fs_devices) {
+ if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
+ ret = 0;
+ break;
+ }
+ fs_devices = fs_devices->seed;
+ }
+ return ret;
+}
+
+#define CORRUPT(reason, eb, root, slot) \
+ btrfs_crit(root->fs_info, "corrupt leaf, %s: block=%llu," \
+ "root=%llu, slot=%d", reason, \
+ btrfs_header_bytenr(eb), root->objectid, slot)
+
+static noinline int check_leaf(struct btrfs_root *root,
+ struct extent_buffer *leaf)
+{
+ struct btrfs_key key;
+ struct btrfs_key leaf_key;
+ u32 nritems = btrfs_header_nritems(leaf);
+ int slot;
+
+ if (nritems == 0)
+ return 0;
+
+ /* Check the 0 item */
+ if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) !=
+ BTRFS_LEAF_DATA_SIZE(root)) {
+ CORRUPT("invalid item offset size pair", leaf, root, 0);
+ return -EIO;
+ }
+
+ /*
+ * Check to make sure each items keys are in the correct order and their
+ * offsets make sense. We only have to loop through nritems-1 because
+ * we check the current slot against the next slot, which verifies the
+ * next slot's offset+size makes sense and that the current's slot
+ * offset is correct.
+ */
+ for (slot = 0; slot < nritems - 1; slot++) {
+ btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
+ btrfs_item_key_to_cpu(leaf, &key, slot + 1);
+
+ /* Make sure the keys are in the right order */
+ if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
+ CORRUPT("bad key order", leaf, root, slot);
+ return -EIO;
+ }
+
+ /*
+ * Make sure the offset and ends are right, remember that the
+ * item data starts at the end of the leaf and grows towards the
+ * front.
+ */
+ if (btrfs_item_offset_nr(leaf, slot) !=
+ btrfs_item_end_nr(leaf, slot + 1)) {
+ CORRUPT("slot offset bad", leaf, root, slot);
+ return -EIO;
+ }
+
+ /*
+ * Check to make sure that we don't point outside of the leaf,
+ * just incase all the items are consistent to eachother, but
+ * all point outside of the leaf.
+ */
+ if (btrfs_item_end_nr(leaf, slot) >
+ BTRFS_LEAF_DATA_SIZE(root)) {
+ CORRUPT("slot end outside of leaf", leaf, root, slot);
+ return -EIO;
+ }
+ }
+
+ return 0;
+}
+
+static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
+ u64 phy_offset, struct page *page,
+ u64 start, u64 end, int mirror)
+{
+ u64 found_start;
+ int found_level;
+ struct extent_buffer *eb;
+ struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
+ int ret = 0;
+ int reads_done;
+
+ if (!page->private)
+ goto out;
+
+ eb = (struct extent_buffer *)page->private;
+
+ /* the pending IO might have been the only thing that kept this buffer
+ * in memory. Make sure we have a ref for all this other checks
+ */
+ extent_buffer_get(eb);
+
+ reads_done = atomic_dec_and_test(&eb->io_pages);
+ if (!reads_done)
+ goto err;
+
+ eb->read_mirror = mirror;
+ if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
+ ret = -EIO;
+ goto err;
+ }
+
+ found_start = btrfs_header_bytenr(eb);
+ if (found_start != eb->start) {
+ printk_ratelimited(KERN_ERR "BTRFS (device %s): bad tree block start "
+ "%llu %llu\n",
+ eb->fs_info->sb->s_id, found_start, eb->start);
+ ret = -EIO;
+ goto err;
+ }
+ if (check_tree_block_fsid(root->fs_info, eb)) {
+ printk_ratelimited(KERN_ERR "BTRFS (device %s): bad fsid on block %llu\n",
+ eb->fs_info->sb->s_id, eb->start);
+ ret = -EIO;
+ goto err;
+ }
+ found_level = btrfs_header_level(eb);
+ if (found_level >= BTRFS_MAX_LEVEL) {
+ btrfs_err(root->fs_info, "bad tree block level %d",
+ (int)btrfs_header_level(eb));
+ ret = -EIO;
+ goto err;
+ }
+
+ btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
+ eb, found_level);
+
+ ret = csum_tree_block(root->fs_info, eb, 1);
+ if (ret) {
+ ret = -EIO;
+ goto err;
+ }
+
+ /*
+ * If this is a leaf block and it is corrupt, set the corrupt bit so
+ * that we don't try and read the other copies of this block, just
+ * return -EIO.
+ */
+ if (found_level == 0 && check_leaf(root, eb)) {
+ set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
+ ret = -EIO;
+ }
+
+ if (!ret)
+ set_extent_buffer_uptodate(eb);
+err:
+ if (reads_done &&
+ test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
+ btree_readahead_hook(root, eb, eb->start, ret);
+
+ if (ret) {
+ /*
+ * our io error hook is going to dec the io pages
+ * again, we have to make sure it has something
+ * to decrement
+ */
+ atomic_inc(&eb->io_pages);
+ clear_extent_buffer_uptodate(eb);
+ }
+ free_extent_buffer(eb);
+out:
+ return ret;
+}
+
+static int btree_io_failed_hook(struct page *page, int failed_mirror)
+{
+ struct extent_buffer *eb;
+ struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
+
+ eb = (struct extent_buffer *)page->private;
+ set_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags);
+ eb->read_mirror = failed_mirror;
+ atomic_dec(&eb->io_pages);
+ if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
+ btree_readahead_hook(root, eb, eb->start, -EIO);
+ return -EIO; /* we fixed nothing */
+}
+
+static void end_workqueue_bio(struct bio *bio, int err)
+{
+ struct btrfs_end_io_wq *end_io_wq = bio->bi_private;
+ struct btrfs_fs_info *fs_info;
+ struct btrfs_workqueue *wq;
+ btrfs_work_func_t func;
+
+ fs_info = end_io_wq->info;
+ end_io_wq->error = err;
+
+ if (bio->bi_rw & REQ_WRITE) {
+ if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA) {
+ wq = fs_info->endio_meta_write_workers;
+ func = btrfs_endio_meta_write_helper;
+ } else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE) {
+ wq = fs_info->endio_freespace_worker;
+ func = btrfs_freespace_write_helper;
+ } else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
+ wq = fs_info->endio_raid56_workers;
+ func = btrfs_endio_raid56_helper;
+ } else {
+ wq = fs_info->endio_write_workers;
+ func = btrfs_endio_write_helper;
+ }
+ } else {
+ if (unlikely(end_io_wq->metadata ==
+ BTRFS_WQ_ENDIO_DIO_REPAIR)) {
+ wq = fs_info->endio_repair_workers;
+ func = btrfs_endio_repair_helper;
+ } else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
+ wq = fs_info->endio_raid56_workers;
+ func = btrfs_endio_raid56_helper;
+ } else if (end_io_wq->metadata) {
+ wq = fs_info->endio_meta_workers;
+ func = btrfs_endio_meta_helper;
+ } else {
+ wq = fs_info->endio_workers;
+ func = btrfs_endio_helper;
+ }
+ }
+
+ btrfs_init_work(&end_io_wq->work, func, end_workqueue_fn, NULL, NULL);
+ btrfs_queue_work(wq, &end_io_wq->work);
+}
+
+int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
+ enum btrfs_wq_endio_type metadata)
+{
+ struct btrfs_end_io_wq *end_io_wq;
+
+ end_io_wq = kmem_cache_alloc(btrfs_end_io_wq_cache, GFP_NOFS);
+ if (!end_io_wq)
+ return -ENOMEM;
+
+ end_io_wq->private = bio->bi_private;
+ end_io_wq->end_io = bio->bi_end_io;
+ end_io_wq->info = info;
+ end_io_wq->error = 0;
+ end_io_wq->bio = bio;
+ end_io_wq->metadata = metadata;
+
+ bio->bi_private = end_io_wq;
+ bio->bi_end_io = end_workqueue_bio;
+ return 0;
+}
+
+unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
+{
+ unsigned long limit = min_t(unsigned long,
+ info->thread_pool_size,
+ info->fs_devices->open_devices);
+ return 256 * limit;
+}
+
+static void run_one_async_start(struct btrfs_work *work)
+{
+ struct async_submit_bio *async;
+ int ret;
+
+ async = container_of(work, struct async_submit_bio, work);
+ ret = async->submit_bio_start(async->inode, async->rw, async->bio,
+ async->mirror_num, async->bio_flags,
+ async->bio_offset);
+ if (ret)
+ async->error = ret;
+}
+
+static void run_one_async_done(struct btrfs_work *work)
+{
+ struct btrfs_fs_info *fs_info;
+ struct async_submit_bio *async;
+ int limit;
+
+ async = container_of(work, struct async_submit_bio, work);
+ fs_info = BTRFS_I(async->inode)->root->fs_info;
+
+ limit = btrfs_async_submit_limit(fs_info);
+ limit = limit * 2 / 3;
+
+ if (atomic_dec_return(&fs_info->nr_async_submits) < limit &&
+ waitqueue_active(&fs_info->async_submit_wait))
+ wake_up(&fs_info->async_submit_wait);
+
+ /* If an error occured we just want to clean up the bio and move on */
+ if (async->error) {
+ bio_endio(async->bio, async->error);
+ return;
+ }
+
+ async->submit_bio_done(async->inode, async->rw, async->bio,
+ async->mirror_num, async->bio_flags,
+ async->bio_offset);
+}
+
+static void run_one_async_free(struct btrfs_work *work)
+{
+ struct async_submit_bio *async;
+
+ async = container_of(work, struct async_submit_bio, work);
+ kfree(async);
+}
+
+int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
+ int rw, struct bio *bio, int mirror_num,
+ unsigned long bio_flags,
+ u64 bio_offset,
+ extent_submit_bio_hook_t *submit_bio_start,
+ extent_submit_bio_hook_t *submit_bio_done)
+{
+ struct async_submit_bio *async;
+
+ async = kmalloc(sizeof(*async), GFP_NOFS);
+ if (!async)
+ return -ENOMEM;
+
+ async->inode = inode;
+ async->rw = rw;
+ async->bio = bio;
+ async->mirror_num = mirror_num;
+ async->submit_bio_start = submit_bio_start;
+ async->submit_bio_done = submit_bio_done;
+
+ btrfs_init_work(&async->work, btrfs_worker_helper, run_one_async_start,
+ run_one_async_done, run_one_async_free);
+
+ async->bio_flags = bio_flags;
+ async->bio_offset = bio_offset;
+
+ async->error = 0;
+
+ atomic_inc(&fs_info->nr_async_submits);
+
+ if (rw & REQ_SYNC)
+ btrfs_set_work_high_priority(&async->work);
+
+ btrfs_queue_work(fs_info->workers, &async->work);
+
+ while (atomic_read(&fs_info->async_submit_draining) &&
+ atomic_read(&fs_info->nr_async_submits)) {
+ wait_event(fs_info->async_submit_wait,
+ (atomic_read(&fs_info->nr_async_submits) == 0));
+ }
+
+ return 0;
+}
+
+static int btree_csum_one_bio(struct bio *bio)
+{
+ struct bio_vec *bvec;
+ struct btrfs_root *root;
+ int i, ret = 0;
+
+ bio_for_each_segment_all(bvec, bio, i) {
+ root = BTRFS_I(bvec->bv_page->mapping->host)->root;
+ ret = csum_dirty_buffer(root->fs_info, bvec->bv_page);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+static int __btree_submit_bio_start(struct inode *inode, int rw,
+ struct bio *bio, int mirror_num,
+ unsigned long bio_flags,
+ u64 bio_offset)
+{
+ /*
+ * when we're called for a write, we're already in the async
+ * submission context. Just jump into btrfs_map_bio
+ */
+ return btree_csum_one_bio(bio);
+}
+
+static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
+ int mirror_num, unsigned long bio_flags,
+ u64 bio_offset)
+{
+ int ret;
+
+ /*
+ * when we're called for a write, we're already in the async
+ * submission context. Just jump into btrfs_map_bio
+ */
+ ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
+ if (ret)
+ bio_endio(bio, ret);
+ return ret;
+}
+
+static int check_async_write(struct inode *inode, unsigned long bio_flags)
+{
+ if (bio_flags & EXTENT_BIO_TREE_LOG)
+ return 0;
+#ifdef CONFIG_X86
+ if (cpu_has_xmm4_2)
+ return 0;
+#endif
+ return 1;
+}
+
+static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
+ int mirror_num, unsigned long bio_flags,
+ u64 bio_offset)
+{
+ int async = check_async_write(inode, bio_flags);
+ int ret;
+
+ if (!(rw & REQ_WRITE)) {
+ /*
+ * called for a read, do the setup so that checksum validation
+ * can happen in the async kernel threads
+ */
+ ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
+ bio, BTRFS_WQ_ENDIO_METADATA);
+ if (ret)
+ goto out_w_error;
+ ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
+ mirror_num, 0);
+ } else if (!async) {
+ ret = btree_csum_one_bio(bio);
+ if (ret)
+ goto out_w_error;
+ ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
+ mirror_num, 0);
+ } else {
+ /*
+ * kthread helpers are used to submit writes so that
+ * checksumming can happen in parallel across all CPUs
+ */
+ ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
+ inode, rw, bio, mirror_num, 0,
+ bio_offset,
+ __btree_submit_bio_start,
+ __btree_submit_bio_done);
+ }
+
+ if (ret) {
+out_w_error:
+ bio_endio(bio, ret);
+ }
+ return ret;
+}
+
+#ifdef CONFIG_MIGRATION
+static int btree_migratepage(struct address_space *mapping,
+ struct page *newpage, struct page *page,
+ enum migrate_mode mode)
+{
+ /*
+ * we can't safely write a btree page from here,
+ * we haven't done the locking hook
+ */
+ if (PageDirty(page))
+ return -EAGAIN;
+ /*
+ * Buffers may be managed in a filesystem specific way.
+ * We must have no buffers or drop them.
+ */
+ if (page_has_private(page) &&
+ !try_to_release_page(page, GFP_KERNEL))
+ return -EAGAIN;
+ return migrate_page(mapping, newpage, page, mode);
+}
+#endif
+
+
+static int btree_writepages(struct address_space *mapping,
+ struct writeback_control *wbc)
+{
+ struct btrfs_fs_info *fs_info;
+ int ret;
+
+ if (wbc->sync_mode == WB_SYNC_NONE) {
+
+ if (wbc->for_kupdate)
+ return 0;
+
+ fs_info = BTRFS_I(mapping->host)->root->fs_info;
+ /* this is a bit racy, but that's ok */
+ ret = percpu_counter_compare(&fs_info->dirty_metadata_bytes,
+ BTRFS_DIRTY_METADATA_THRESH);
+ if (ret < 0)
+ return 0;
+ }
+ return btree_write_cache_pages(mapping, wbc);
+}
+
+static int btree_readpage(struct file *file, struct page *page)
+{
+ struct extent_io_tree *tree;
+ tree = &BTRFS_I(page->mapping->host)->io_tree;
+ return extent_read_full_page(tree, page, btree_get_extent, 0);
+}
+
+static int btree_releasepage(struct page *page, gfp_t gfp_flags)
+{
+ if (PageWriteback(page) || PageDirty(page))
+ return 0;
+
+ return try_release_extent_buffer(page);
+}
+
+static void btree_invalidatepage(struct page *page, unsigned int offset,
+ unsigned int length)
+{
+ struct extent_io_tree *tree;
+ tree = &BTRFS_I(page->mapping->host)->io_tree;
+ extent_invalidatepage(tree, page, offset);
+ btree_releasepage(page, GFP_NOFS);
+ if (PagePrivate(page)) {
+ btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info,
+ "page private not zero on page %llu",
+ (unsigned long long)page_offset(page));
+ ClearPagePrivate(page);
+ set_page_private(page, 0);
+ page_cache_release(page);
+ }
+}
+
+static int btree_set_page_dirty(struct page *page)
+{
+#ifdef DEBUG
+ struct extent_buffer *eb;
+
+ BUG_ON(!PagePrivate(page));
+ eb = (struct extent_buffer *)page->private;
+ BUG_ON(!eb);
+ BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
+ BUG_ON(!atomic_read(&eb->refs));
+ btrfs_assert_tree_locked(eb);
+#endif
+ return __set_page_dirty_nobuffers(page);
+}
+
+static const struct address_space_operations btree_aops = {
+ .readpage = btree_readpage,
+ .writepages = btree_writepages,
+ .releasepage = btree_releasepage,
+ .invalidatepage = btree_invalidatepage,
+#ifdef CONFIG_MIGRATION
+ .migratepage = btree_migratepage,
+#endif
+ .set_page_dirty = btree_set_page_dirty,
+};
+
+void readahead_tree_block(struct btrfs_root *root, u64 bytenr)
+{
+ struct extent_buffer *buf = NULL;
+ struct inode *btree_inode = root->fs_info->btree_inode;
+
+ buf = btrfs_find_create_tree_block(root, bytenr);
+ if (!buf)
+ return;
+ read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
+ buf, 0, WAIT_NONE, btree_get_extent, 0);
+ free_extent_buffer(buf);
+}
+
+int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr,
+ int mirror_num, struct extent_buffer **eb)
+{
+ struct extent_buffer *buf = NULL;
+ struct inode *btree_inode = root->fs_info->btree_inode;
+ struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
+ int ret;
+
+ buf = btrfs_find_create_tree_block(root, bytenr);
+ if (!buf)
+ return 0;
+
+ set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
+
+ ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
+ btree_get_extent, mirror_num);
+ if (ret) {
+ free_extent_buffer(buf);
+ return ret;
+ }
+
+ if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
+ free_extent_buffer(buf);
+ return -EIO;
+ } else if (extent_buffer_uptodate(buf)) {
+ *eb = buf;
+ } else {
+ free_extent_buffer(buf);
+ }
+ return 0;
+}
+
+struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info,
+ u64 bytenr)
+{
+ return find_extent_buffer(fs_info, bytenr);
+}
+
+struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
+ u64 bytenr)
+{
+ if (btrfs_test_is_dummy_root(root))
+ return alloc_test_extent_buffer(root->fs_info, bytenr);
+ return alloc_extent_buffer(root->fs_info, bytenr);
+}
+
+
+int btrfs_write_tree_block(struct extent_buffer *buf)
+{
+ return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start,
+ buf->start + buf->len - 1);
+}
+
+int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
+{
+ return filemap_fdatawait_range(buf->pages[0]->mapping,
+ buf->start, buf->start + buf->len - 1);
+}
+
+struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
+ u64 parent_transid)
+{
+ struct extent_buffer *buf = NULL;
+ int ret;
+
+ buf = btrfs_find_create_tree_block(root, bytenr);
+ if (!buf)
+ return NULL;
+
+ ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
+ if (ret) {
+ free_extent_buffer(buf);
+ return NULL;
+ }
+ return buf;
+
+}
+
+void clean_tree_block(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info,
+ struct extent_buffer *buf)
+{
+ if (btrfs_header_generation(buf) ==
+ fs_info->running_transaction->transid) {
+ btrfs_assert_tree_locked(buf);
+
+ if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
+ __percpu_counter_add(&fs_info->dirty_metadata_bytes,
+ -buf->len,
+ fs_info->dirty_metadata_batch);
+ /* ugh, clear_extent_buffer_dirty needs to lock the page */
+ btrfs_set_lock_blocking(buf);
+ clear_extent_buffer_dirty(buf);
+ }
+ }
+}
+
+static struct btrfs_subvolume_writers *btrfs_alloc_subvolume_writers(void)
+{
+ struct btrfs_subvolume_writers *writers;
+ int ret;
+
+ writers = kmalloc(sizeof(*writers), GFP_NOFS);
+ if (!writers)
+ return ERR_PTR(-ENOMEM);
+
+ ret = percpu_counter_init(&writers->counter, 0, GFP_KERNEL);
+ if (ret < 0) {
+ kfree(writers);
+ return ERR_PTR(ret);
+ }
+
+ init_waitqueue_head(&writers->wait);
+ return writers;
+}
+
+static void
+btrfs_free_subvolume_writers(struct btrfs_subvolume_writers *writers)
+{
+ percpu_counter_destroy(&writers->counter);
+ kfree(writers);
+}
+
+static void __setup_root(u32 nodesize, u32 sectorsize, u32 stripesize,
+ struct btrfs_root *root, struct btrfs_fs_info *fs_info,
+ u64 objectid)
+{
+ root->node = NULL;
+ root->commit_root = NULL;
+ root->sectorsize = sectorsize;
+ root->nodesize = nodesize;
+ root->stripesize = stripesize;
+ root->state = 0;
+ root->orphan_cleanup_state = 0;
+
+ root->objectid = objectid;
+ root->last_trans = 0;
+ root->highest_objectid = 0;
+ root->nr_delalloc_inodes = 0;
+ root->nr_ordered_extents = 0;
+ root->name = NULL;
+ root->inode_tree = RB_ROOT;
+ INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
+ root->block_rsv = NULL;
+ root->orphan_block_rsv = NULL;
+
+ INIT_LIST_HEAD(&root->dirty_list);
+ INIT_LIST_HEAD(&root->root_list);
+ INIT_LIST_HEAD(&root->delalloc_inodes);
+ INIT_LIST_HEAD(&root->delalloc_root);
+ INIT_LIST_HEAD(&root->ordered_extents);
+ INIT_LIST_HEAD(&root->ordered_root);
+ INIT_LIST_HEAD(&root->logged_list[0]);
+ INIT_LIST_HEAD(&root->logged_list[1]);
+ spin_lock_init(&root->orphan_lock);
+ spin_lock_init(&root->inode_lock);
+ spin_lock_init(&root->delalloc_lock);
+ spin_lock_init(&root->ordered_extent_lock);
+ spin_lock_init(&root->accounting_lock);
+ spin_lock_init(&root->log_extents_lock[0]);
+ spin_lock_init(&root->log_extents_lock[1]);
+ mutex_init(&root->objectid_mutex);
+ mutex_init(&root->log_mutex);
+ mutex_init(&root->ordered_extent_mutex);
+ mutex_init(&root->delalloc_mutex);
+ init_waitqueue_head(&root->log_writer_wait);
+ init_waitqueue_head(&root->log_commit_wait[0]);
+ init_waitqueue_head(&root->log_commit_wait[1]);
+ INIT_LIST_HEAD(&root->log_ctxs[0]);
+ INIT_LIST_HEAD(&root->log_ctxs[1]);
+ atomic_set(&root->log_commit[0], 0);
+ atomic_set(&root->log_commit[1], 0);
+ atomic_set(&root->log_writers, 0);
+ atomic_set(&root->log_batch, 0);
+ atomic_set(&root->orphan_inodes, 0);
+ atomic_set(&root->refs, 1);
+ atomic_set(&root->will_be_snapshoted, 0);
+ root->log_transid = 0;
+ root->log_transid_committed = -1;
+ root->last_log_commit = 0;
+ if (fs_info)
+ extent_io_tree_init(&root->dirty_log_pages,
+ fs_info->btree_inode->i_mapping);
+
+ memset(&root->root_key, 0, sizeof(root->root_key));
+ memset(&root->root_item, 0, sizeof(root->root_item));
+ memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
+ if (fs_info)
+ root->defrag_trans_start = fs_info->generation;
+ else
+ root->defrag_trans_start = 0;
+ root->root_key.objectid = objectid;
+ root->anon_dev = 0;
+
+ spin_lock_init(&root->root_item_lock);
+}
+
+static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *root = kzalloc(sizeof(*root), GFP_NOFS);
+ if (root)
+ root->fs_info = fs_info;
+ return root;
+}
+
+#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
+/* Should only be used by the testing infrastructure */
+struct btrfs_root *btrfs_alloc_dummy_root(void)
+{
+ struct btrfs_root *root;
+
+ root = btrfs_alloc_root(NULL);
+ if (!root)
+ return ERR_PTR(-ENOMEM);
+ __setup_root(4096, 4096, 4096, root, NULL, 1);
+ set_bit(BTRFS_ROOT_DUMMY_ROOT, &root->state);
+ root->alloc_bytenr = 0;
+
+ return root;
+}
+#endif
+
+struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info,
+ u64 objectid)
+{
+ struct extent_buffer *leaf;
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ struct btrfs_root *root;
+ struct btrfs_key key;
+ int ret = 0;
+ uuid_le uuid;
+
+ root = btrfs_alloc_root(fs_info);
+ if (!root)
+ return ERR_PTR(-ENOMEM);
+
+ __setup_root(tree_root->nodesize, tree_root->sectorsize,
+ tree_root->stripesize, root, fs_info, objectid);
+ root->root_key.objectid = objectid;
+ root->root_key.type = BTRFS_ROOT_ITEM_KEY;
+ root->root_key.offset = 0;
+
+ leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
+ if (IS_ERR(leaf)) {
+ ret = PTR_ERR(leaf);
+ leaf = NULL;
+ goto fail;
+ }
+
+ memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
+ btrfs_set_header_bytenr(leaf, leaf->start);
+ btrfs_set_header_generation(leaf, trans->transid);
+ btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
+ btrfs_set_header_owner(leaf, objectid);
+ root->node = leaf;
+
+ write_extent_buffer(leaf, fs_info->fsid, btrfs_header_fsid(),
+ BTRFS_FSID_SIZE);
+ write_extent_buffer(leaf, fs_info->chunk_tree_uuid,
+ btrfs_header_chunk_tree_uuid(leaf),
+ BTRFS_UUID_SIZE);
+ btrfs_mark_buffer_dirty(leaf);
+
+ root->commit_root = btrfs_root_node(root);
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+
+ root->root_item.flags = 0;
+ root->root_item.byte_limit = 0;
+ btrfs_set_root_bytenr(&root->root_item, leaf->start);
+ btrfs_set_root_generation(&root->root_item, trans->transid);
+ btrfs_set_root_level(&root->root_item, 0);
+ btrfs_set_root_refs(&root->root_item, 1);
+ btrfs_set_root_used(&root->root_item, leaf->len);
+ btrfs_set_root_last_snapshot(&root->root_item, 0);
+ btrfs_set_root_dirid(&root->root_item, 0);
+ uuid_le_gen(&uuid);
+ memcpy(root->root_item.uuid, uuid.b, BTRFS_UUID_SIZE);
+ root->root_item.drop_level = 0;
+
+ key.objectid = objectid;
+ key.type = BTRFS_ROOT_ITEM_KEY;
+ key.offset = 0;
+ ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
+ if (ret)
+ goto fail;
+
+ btrfs_tree_unlock(leaf);
+
+ return root;
+
+fail:
+ if (leaf) {
+ btrfs_tree_unlock(leaf);
+ free_extent_buffer(root->commit_root);
+ free_extent_buffer(leaf);
+ }
+ kfree(root);
+
+ return ERR_PTR(ret);
+}
+
+static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *root;
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ struct extent_buffer *leaf;
+
+ root = btrfs_alloc_root(fs_info);
+ if (!root)
+ return ERR_PTR(-ENOMEM);
+
+ __setup_root(tree_root->nodesize, tree_root->sectorsize,
+ tree_root->stripesize, root, fs_info,
+ BTRFS_TREE_LOG_OBJECTID);
+
+ root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
+ root->root_key.type = BTRFS_ROOT_ITEM_KEY;
+ root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
+
+ /*
+ * DON'T set REF_COWS for log trees
+ *
+ * log trees do not get reference counted because they go away
+ * before a real commit is actually done. They do store pointers
+ * to file data extents, and those reference counts still get
+ * updated (along with back refs to the log tree).
+ */
+
+ leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
+ NULL, 0, 0, 0);
+ if (IS_ERR(leaf)) {
+ kfree(root);
+ return ERR_CAST(leaf);
+ }
+
+ memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
+ btrfs_set_header_bytenr(leaf, leaf->start);
+ btrfs_set_header_generation(leaf, trans->transid);
+ btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
+ btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
+ root->node = leaf;
+
+ write_extent_buffer(root->node, root->fs_info->fsid,
+ btrfs_header_fsid(), BTRFS_FSID_SIZE);
+ btrfs_mark_buffer_dirty(root->node);
+ btrfs_tree_unlock(root->node);
+ return root;
+}
+
+int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *log_root;
+
+ log_root = alloc_log_tree(trans, fs_info);
+ if (IS_ERR(log_root))
+ return PTR_ERR(log_root);
+ WARN_ON(fs_info->log_root_tree);
+ fs_info->log_root_tree = log_root;
+ return 0;
+}
+
+int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_root *log_root;
+ struct btrfs_inode_item *inode_item;
+
+ log_root = alloc_log_tree(trans, root->fs_info);
+ if (IS_ERR(log_root))
+ return PTR_ERR(log_root);
+
+ log_root->last_trans = trans->transid;
+ log_root->root_key.offset = root->root_key.objectid;
+
+ inode_item = &log_root->root_item.inode;
+ btrfs_set_stack_inode_generation(inode_item, 1);
+ btrfs_set_stack_inode_size(inode_item, 3);
+ btrfs_set_stack_inode_nlink(inode_item, 1);
+ btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
+ btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
+
+ btrfs_set_root_node(&log_root->root_item, log_root->node);
+
+ WARN_ON(root->log_root);
+ root->log_root = log_root;
+ root->log_transid = 0;
+ root->log_transid_committed = -1;
+ root->last_log_commit = 0;
+ return 0;
+}
+
+static struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
+ struct btrfs_key *key)
+{
+ struct btrfs_root *root;
+ struct btrfs_fs_info *fs_info = tree_root->fs_info;
+ struct btrfs_path *path;
+ u64 generation;
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return ERR_PTR(-ENOMEM);
+
+ root = btrfs_alloc_root(fs_info);
+ if (!root) {
+ ret = -ENOMEM;
+ goto alloc_fail;
+ }
+
+ __setup_root(tree_root->nodesize, tree_root->sectorsize,
+ tree_root->stripesize, root, fs_info, key->objectid);
+
+ ret = btrfs_find_root(tree_root, key, path,
+ &root->root_item, &root->root_key);
+ if (ret) {
+ if (ret > 0)
+ ret = -ENOENT;
+ goto find_fail;
+ }
+
+ generation = btrfs_root_generation(&root->root_item);
+ root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
+ generation);
+ if (!root->node) {
+ ret = -ENOMEM;
+ goto find_fail;
+ } else if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
+ ret = -EIO;
+ goto read_fail;
+ }
+ root->commit_root = btrfs_root_node(root);
+out:
+ btrfs_free_path(path);
+ return root;
+
+read_fail:
+ free_extent_buffer(root->node);
+find_fail:
+ kfree(root);
+alloc_fail:
+ root = ERR_PTR(ret);
+ goto out;
+}
+
+struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
+ struct btrfs_key *location)
+{
+ struct btrfs_root *root;
+
+ root = btrfs_read_tree_root(tree_root, location);
+ if (IS_ERR(root))
+ return root;
+
+ if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
+ set_bit(BTRFS_ROOT_REF_COWS, &root->state);
+ btrfs_check_and_init_root_item(&root->root_item);
+ }
+
+ return root;
+}
+
+int btrfs_init_fs_root(struct btrfs_root *root)
+{
+ int ret;
+ struct btrfs_subvolume_writers *writers;
+
+ root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
+ root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
+ GFP_NOFS);
+ if (!root->free_ino_pinned || !root->free_ino_ctl) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ writers = btrfs_alloc_subvolume_writers();
+ if (IS_ERR(writers)) {
+ ret = PTR_ERR(writers);
+ goto fail;
+ }
+ root->subv_writers = writers;
+
+ btrfs_init_free_ino_ctl(root);
+ spin_lock_init(&root->ino_cache_lock);
+ init_waitqueue_head(&root->ino_cache_wait);
+
+ ret = get_anon_bdev(&root->anon_dev);
+ if (ret)
+ goto free_writers;
+ return 0;
+
+free_writers:
+ btrfs_free_subvolume_writers(root->subv_writers);
+fail:
+ kfree(root->free_ino_ctl);
+ kfree(root->free_ino_pinned);
+ return ret;
+}
+
+static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
+ u64 root_id)
+{
+ struct btrfs_root *root;
+
+ spin_lock(&fs_info->fs_roots_radix_lock);
+ root = radix_tree_lookup(&fs_info->fs_roots_radix,
+ (unsigned long)root_id);
+ spin_unlock(&fs_info->fs_roots_radix_lock);
+ return root;
+}
+
+int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
+ struct btrfs_root *root)
+{
+ int ret;
+
+ ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
+ if (ret)
+ return ret;
+
+ spin_lock(&fs_info->fs_roots_radix_lock);
+ ret = radix_tree_insert(&fs_info->fs_roots_radix,
+ (unsigned long)root->root_key.objectid,
+ root);
+ if (ret == 0)
+ set_bit(BTRFS_ROOT_IN_RADIX, &root->state);
+ spin_unlock(&fs_info->fs_roots_radix_lock);
+ radix_tree_preload_end();
+
+ return ret;
+}
+
+struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
+ struct btrfs_key *location,
+ bool check_ref)
+{
+ struct btrfs_root *root;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ int ret;
+
+ if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
+ return fs_info->tree_root;
+ if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
+ return fs_info->extent_root;
+ if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
+ return fs_info->chunk_root;
+ if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
+ return fs_info->dev_root;
+ if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
+ return fs_info->csum_root;
+ if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
+ return fs_info->quota_root ? fs_info->quota_root :
+ ERR_PTR(-ENOENT);
+ if (location->objectid == BTRFS_UUID_TREE_OBJECTID)
+ return fs_info->uuid_root ? fs_info->uuid_root :
+ ERR_PTR(-ENOENT);
+again:
+ root = btrfs_lookup_fs_root(fs_info, location->objectid);
+ if (root) {
+ if (check_ref && btrfs_root_refs(&root->root_item) == 0)
+ return ERR_PTR(-ENOENT);
+ return root;
+ }
+
+ root = btrfs_read_fs_root(fs_info->tree_root, location);
+ if (IS_ERR(root))
+ return root;
+
+ if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
+ ret = -ENOENT;
+ goto fail;
+ }
+
+ ret = btrfs_init_fs_root(root);
+ if (ret)
+ goto fail;
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ key.objectid = BTRFS_ORPHAN_OBJECTID;
+ key.type = BTRFS_ORPHAN_ITEM_KEY;
+ key.offset = location->objectid;
+
+ ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
+ btrfs_free_path(path);
+ if (ret < 0)
+ goto fail;
+ if (ret == 0)
+ set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
+
+ ret = btrfs_insert_fs_root(fs_info, root);
+ if (ret) {
+ if (ret == -EEXIST) {
+ free_fs_root(root);
+ goto again;
+ }
+ goto fail;
+ }
+ return root;
+fail:
+ free_fs_root(root);
+ return ERR_PTR(ret);
+}
+
+static int btrfs_congested_fn(void *congested_data, int bdi_bits)
+{
+ struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
+ int ret = 0;
+ struct btrfs_device *device;
+ struct backing_dev_info *bdi;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
+ if (!device->bdev)
+ continue;
+ bdi = blk_get_backing_dev_info(device->bdev);
+ if (bdi_congested(bdi, bdi_bits)) {
+ ret = 1;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
+{
+ int err;
+
+ err = bdi_setup_and_register(bdi, "btrfs");
+ if (err)
+ return err;
+
+ bdi->ra_pages = VM_MAX_READAHEAD * 1024 / PAGE_CACHE_SIZE;
+ bdi->congested_fn = btrfs_congested_fn;
+ bdi->congested_data = info;
+ return 0;
+}
+
+/*
+ * called by the kthread helper functions to finally call the bio end_io
+ * functions. This is where read checksum verification actually happens
+ */
+static void end_workqueue_fn(struct btrfs_work *work)
+{
+ struct bio *bio;
+ struct btrfs_end_io_wq *end_io_wq;
+ int error;
+
+ end_io_wq = container_of(work, struct btrfs_end_io_wq, work);
+ bio = end_io_wq->bio;
+
+ error = end_io_wq->error;
+ bio->bi_private = end_io_wq->private;
+ bio->bi_end_io = end_io_wq->end_io;
+ kmem_cache_free(btrfs_end_io_wq_cache, end_io_wq);
+ bio_endio_nodec(bio, error);
+}
+
+static int cleaner_kthread(void *arg)
+{
+ struct btrfs_root *root = arg;
+ int again;
+
+ do {
+ again = 0;
+
+ /* Make the cleaner go to sleep early. */
+ if (btrfs_need_cleaner_sleep(root))
+ goto sleep;
+
+ if (!mutex_trylock(&root->fs_info->cleaner_mutex))
+ goto sleep;
+
+ /*
+ * Avoid the problem that we change the status of the fs
+ * during the above check and trylock.
+ */
+ if (btrfs_need_cleaner_sleep(root)) {
+ mutex_unlock(&root->fs_info->cleaner_mutex);
+ goto sleep;
+ }
+
+ btrfs_run_delayed_iputs(root);
+ btrfs_delete_unused_bgs(root->fs_info);
+ again = btrfs_clean_one_deleted_snapshot(root);
+ mutex_unlock(&root->fs_info->cleaner_mutex);
+
+ /*
+ * The defragger has dealt with the R/O remount and umount,
+ * needn't do anything special here.
+ */
+ btrfs_run_defrag_inodes(root->fs_info);
+sleep:
+ if (!try_to_freeze() && !again) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (!kthread_should_stop())
+ schedule();
+ __set_current_state(TASK_RUNNING);
+ }
+ } while (!kthread_should_stop());
+ return 0;
+}
+
+static int transaction_kthread(void *arg)
+{
+ struct btrfs_root *root = arg;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_transaction *cur;
+ u64 transid;
+ unsigned long now;
+ unsigned long delay;
+ bool cannot_commit;
+
+ do {
+ cannot_commit = false;
+ delay = HZ * root->fs_info->commit_interval;
+ mutex_lock(&root->fs_info->transaction_kthread_mutex);
+
+ spin_lock(&root->fs_info->trans_lock);
+ cur = root->fs_info->running_transaction;
+ if (!cur) {
+ spin_unlock(&root->fs_info->trans_lock);
+ goto sleep;
+ }
+
+ now = get_seconds();
+ if (cur->state < TRANS_STATE_BLOCKED &&
+ (now < cur->start_time ||
+ now - cur->start_time < root->fs_info->commit_interval)) {
+ spin_unlock(&root->fs_info->trans_lock);
+ delay = HZ * 5;
+ goto sleep;
+ }
+ transid = cur->transid;
+ spin_unlock(&root->fs_info->trans_lock);
+
+ /* If the file system is aborted, this will always fail. */
+ trans = btrfs_attach_transaction(root);
+ if (IS_ERR(trans)) {
+ if (PTR_ERR(trans) != -ENOENT)
+ cannot_commit = true;
+ goto sleep;
+ }
+ if (transid == trans->transid) {
+ btrfs_commit_transaction(trans, root);
+ } else {
+ btrfs_end_transaction(trans, root);
+ }
+sleep:
+ wake_up_process(root->fs_info->cleaner_kthread);
+ mutex_unlock(&root->fs_info->transaction_kthread_mutex);
+
+ if (unlikely(test_bit(BTRFS_FS_STATE_ERROR,
+ &root->fs_info->fs_state)))
+ btrfs_cleanup_transaction(root);
+ if (!try_to_freeze()) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (!kthread_should_stop() &&
+ (!btrfs_transaction_blocked(root->fs_info) ||
+ cannot_commit))
+ schedule_timeout(delay);
+ __set_current_state(TASK_RUNNING);
+ }
+ } while (!kthread_should_stop());
+ return 0;
+}
+
+/*
+ * this will find the highest generation in the array of
+ * root backups. The index of the highest array is returned,
+ * or -1 if we can't find anything.
+ *
+ * We check to make sure the array is valid by comparing the
+ * generation of the latest root in the array with the generation
+ * in the super block. If they don't match we pitch it.
+ */
+static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
+{
+ u64 cur;
+ int newest_index = -1;
+ struct btrfs_root_backup *root_backup;
+ int i;
+
+ for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
+ root_backup = info->super_copy->super_roots + i;
+ cur = btrfs_backup_tree_root_gen(root_backup);
+ if (cur == newest_gen)
+ newest_index = i;
+ }
+
+ /* check to see if we actually wrapped around */
+ if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
+ root_backup = info->super_copy->super_roots;
+ cur = btrfs_backup_tree_root_gen(root_backup);
+ if (cur == newest_gen)
+ newest_index = 0;
+ }
+ return newest_index;
+}
+
+
+/*
+ * find the oldest backup so we know where to store new entries
+ * in the backup array. This will set the backup_root_index
+ * field in the fs_info struct
+ */
+static void find_oldest_super_backup(struct btrfs_fs_info *info,
+ u64 newest_gen)
+{
+ int newest_index = -1;
+
+ newest_index = find_newest_super_backup(info, newest_gen);
+ /* if there was garbage in there, just move along */
+ if (newest_index == -1) {
+ info->backup_root_index = 0;
+ } else {
+ info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
+ }
+}
+
+/*
+ * copy all the root pointers into the super backup array.
+ * this will bump the backup pointer by one when it is
+ * done
+ */
+static void backup_super_roots(struct btrfs_fs_info *info)
+{
+ int next_backup;
+ struct btrfs_root_backup *root_backup;
+ int last_backup;
+
+ next_backup = info->backup_root_index;
+ last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
+ BTRFS_NUM_BACKUP_ROOTS;
+
+ /*
+ * just overwrite the last backup if we're at the same generation
+ * this happens only at umount
+ */
+ root_backup = info->super_for_commit->super_roots + last_backup;
+ if (btrfs_backup_tree_root_gen(root_backup) ==
+ btrfs_header_generation(info->tree_root->node))
+ next_backup = last_backup;
+
+ root_backup = info->super_for_commit->super_roots + next_backup;
+
+ /*
+ * make sure all of our padding and empty slots get zero filled
+ * regardless of which ones we use today
+ */
+ memset(root_backup, 0, sizeof(*root_backup));
+
+ info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
+
+ btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
+ btrfs_set_backup_tree_root_gen(root_backup,
+ btrfs_header_generation(info->tree_root->node));
+
+ btrfs_set_backup_tree_root_level(root_backup,
+ btrfs_header_level(info->tree_root->node));
+
+ btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
+ btrfs_set_backup_chunk_root_gen(root_backup,
+ btrfs_header_generation(info->chunk_root->node));
+ btrfs_set_backup_chunk_root_level(root_backup,
+ btrfs_header_level(info->chunk_root->node));
+
+ btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
+ btrfs_set_backup_extent_root_gen(root_backup,
+ btrfs_header_generation(info->extent_root->node));
+ btrfs_set_backup_extent_root_level(root_backup,
+ btrfs_header_level(info->extent_root->node));
+
+ /*
+ * we might commit during log recovery, which happens before we set
+ * the fs_root. Make sure it is valid before we fill it in.
+ */
+ if (info->fs_root && info->fs_root->node) {
+ btrfs_set_backup_fs_root(root_backup,
+ info->fs_root->node->start);
+ btrfs_set_backup_fs_root_gen(root_backup,
+ btrfs_header_generation(info->fs_root->node));
+ btrfs_set_backup_fs_root_level(root_backup,
+ btrfs_header_level(info->fs_root->node));
+ }
+
+ btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
+ btrfs_set_backup_dev_root_gen(root_backup,
+ btrfs_header_generation(info->dev_root->node));
+ btrfs_set_backup_dev_root_level(root_backup,
+ btrfs_header_level(info->dev_root->node));
+
+ btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
+ btrfs_set_backup_csum_root_gen(root_backup,
+ btrfs_header_generation(info->csum_root->node));
+ btrfs_set_backup_csum_root_level(root_backup,
+ btrfs_header_level(info->csum_root->node));
+
+ btrfs_set_backup_total_bytes(root_backup,
+ btrfs_super_total_bytes(info->super_copy));
+ btrfs_set_backup_bytes_used(root_backup,
+ btrfs_super_bytes_used(info->super_copy));
+ btrfs_set_backup_num_devices(root_backup,
+ btrfs_super_num_devices(info->super_copy));
+
+ /*
+ * if we don't copy this out to the super_copy, it won't get remembered
+ * for the next commit
+ */
+ memcpy(&info->super_copy->super_roots,
+ &info->super_for_commit->super_roots,
+ sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
+}
+
+/*
+ * this copies info out of the root backup array and back into
+ * the in-memory super block. It is meant to help iterate through
+ * the array, so you send it the number of backups you've already
+ * tried and the last backup index you used.
+ *
+ * this returns -1 when it has tried all the backups
+ */
+static noinline int next_root_backup(struct btrfs_fs_info *info,
+ struct btrfs_super_block *super,
+ int *num_backups_tried, int *backup_index)
+{
+ struct btrfs_root_backup *root_backup;
+ int newest = *backup_index;
+
+ if (*num_backups_tried == 0) {
+ u64 gen = btrfs_super_generation(super);
+
+ newest = find_newest_super_backup(info, gen);
+ if (newest == -1)
+ return -1;
+
+ *backup_index = newest;
+ *num_backups_tried = 1;
+ } else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
+ /* we've tried all the backups, all done */
+ return -1;
+ } else {
+ /* jump to the next oldest backup */
+ newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
+ BTRFS_NUM_BACKUP_ROOTS;
+ *backup_index = newest;
+ *num_backups_tried += 1;
+ }
+ root_backup = super->super_roots + newest;
+
+ btrfs_set_super_generation(super,
+ btrfs_backup_tree_root_gen(root_backup));
+ btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
+ btrfs_set_super_root_level(super,
+ btrfs_backup_tree_root_level(root_backup));
+ btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
+
+ /*
+ * fixme: the total bytes and num_devices need to match or we should
+ * need a fsck
+ */
+ btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
+ btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
+ return 0;
+}
+
+/* helper to cleanup workers */
+static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
+{
+ btrfs_destroy_workqueue(fs_info->fixup_workers);
+ btrfs_destroy_workqueue(fs_info->delalloc_workers);
+ btrfs_destroy_workqueue(fs_info->workers);
+ btrfs_destroy_workqueue(fs_info->endio_workers);
+ btrfs_destroy_workqueue(fs_info->endio_meta_workers);
+ btrfs_destroy_workqueue(fs_info->endio_raid56_workers);
+ btrfs_destroy_workqueue(fs_info->endio_repair_workers);
+ btrfs_destroy_workqueue(fs_info->rmw_workers);
+ btrfs_destroy_workqueue(fs_info->endio_meta_write_workers);
+ btrfs_destroy_workqueue(fs_info->endio_write_workers);
+ btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
+ btrfs_destroy_workqueue(fs_info->submit_workers);
+ btrfs_destroy_workqueue(fs_info->delayed_workers);
+ btrfs_destroy_workqueue(fs_info->caching_workers);
+ btrfs_destroy_workqueue(fs_info->readahead_workers);
+ btrfs_destroy_workqueue(fs_info->flush_workers);
+ btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
+ btrfs_destroy_workqueue(fs_info->extent_workers);
+}
+
+static void free_root_extent_buffers(struct btrfs_root *root)
+{
+ if (root) {
+ free_extent_buffer(root->node);
+ free_extent_buffer(root->commit_root);
+ root->node = NULL;
+ root->commit_root = NULL;
+ }
+}
+
+/* helper to cleanup tree roots */
+static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
+{
+ free_root_extent_buffers(info->tree_root);
+
+ free_root_extent_buffers(info->dev_root);
+ free_root_extent_buffers(info->extent_root);
+ free_root_extent_buffers(info->csum_root);
+ free_root_extent_buffers(info->quota_root);
+ free_root_extent_buffers(info->uuid_root);
+ if (chunk_root)
+ free_root_extent_buffers(info->chunk_root);
+}
+
+void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
+{
+ int ret;
+ struct btrfs_root *gang[8];
+ int i;
+
+ while (!list_empty(&fs_info->dead_roots)) {
+ gang[0] = list_entry(fs_info->dead_roots.next,
+ struct btrfs_root, root_list);
+ list_del(&gang[0]->root_list);
+
+ if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state)) {
+ btrfs_drop_and_free_fs_root(fs_info, gang[0]);
+ } else {
+ free_extent_buffer(gang[0]->node);
+ free_extent_buffer(gang[0]->commit_root);
+ btrfs_put_fs_root(gang[0]);
+ }
+ }
+
+ while (1) {
+ ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
+ (void **)gang, 0,
+ ARRAY_SIZE(gang));
+ if (!ret)
+ break;
+ for (i = 0; i < ret; i++)
+ btrfs_drop_and_free_fs_root(fs_info, gang[i]);
+ }
+
+ if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
+ btrfs_free_log_root_tree(NULL, fs_info);
+ btrfs_destroy_pinned_extent(fs_info->tree_root,
+ fs_info->pinned_extents);
+ }
+}
+
+static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
+{
+ mutex_init(&fs_info->scrub_lock);
+ atomic_set(&fs_info->scrubs_running, 0);
+ atomic_set(&fs_info->scrub_pause_req, 0);
+ atomic_set(&fs_info->scrubs_paused, 0);
+ atomic_set(&fs_info->scrub_cancel_req, 0);
+ init_waitqueue_head(&fs_info->scrub_pause_wait);
+ fs_info->scrub_workers_refcnt = 0;
+}
+
+static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
+{
+ spin_lock_init(&fs_info->balance_lock);
+ mutex_init(&fs_info->balance_mutex);
+ atomic_set(&fs_info->balance_running, 0);
+ atomic_set(&fs_info->balance_pause_req, 0);
+ atomic_set(&fs_info->balance_cancel_req, 0);
+ fs_info->balance_ctl = NULL;
+ init_waitqueue_head(&fs_info->balance_wait_q);
+}
+
+static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info,
+ struct btrfs_root *tree_root)
+{
+ fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
+ set_nlink(fs_info->btree_inode, 1);
+ /*
+ * we set the i_size on the btree inode to the max possible int.
+ * the real end of the address space is determined by all of
+ * the devices in the system
+ */
+ fs_info->btree_inode->i_size = OFFSET_MAX;
+ fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
+
+ RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
+ extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
+ fs_info->btree_inode->i_mapping);
+ BTRFS_I(fs_info->btree_inode)->io_tree.track_uptodate = 0;
+ extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
+
+ BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
+
+ BTRFS_I(fs_info->btree_inode)->root = tree_root;
+ memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
+ sizeof(struct btrfs_key));
+ set_bit(BTRFS_INODE_DUMMY,
+ &BTRFS_I(fs_info->btree_inode)->runtime_flags);
+ btrfs_insert_inode_hash(fs_info->btree_inode);
+}
+
+static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
+{
+ fs_info->dev_replace.lock_owner = 0;
+ atomic_set(&fs_info->dev_replace.nesting_level, 0);
+ mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
+ mutex_init(&fs_info->dev_replace.lock_management_lock);
+ mutex_init(&fs_info->dev_replace.lock);
+ init_waitqueue_head(&fs_info->replace_wait);
+}
+
+static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
+{
+ spin_lock_init(&fs_info->qgroup_lock);
+ mutex_init(&fs_info->qgroup_ioctl_lock);
+ fs_info->qgroup_tree = RB_ROOT;
+ fs_info->qgroup_op_tree = RB_ROOT;
+ INIT_LIST_HEAD(&fs_info->dirty_qgroups);
+ fs_info->qgroup_seq = 1;
+ fs_info->quota_enabled = 0;
+ fs_info->pending_quota_state = 0;
+ fs_info->qgroup_ulist = NULL;
+ mutex_init(&fs_info->qgroup_rescan_lock);
+}
+
+static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
+ struct btrfs_fs_devices *fs_devices)
+{
+ int max_active = fs_info->thread_pool_size;
+ unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
+
+ fs_info->workers =
+ btrfs_alloc_workqueue("worker", flags | WQ_HIGHPRI,
+ max_active, 16);
+
+ fs_info->delalloc_workers =
+ btrfs_alloc_workqueue("delalloc", flags, max_active, 2);
+
+ fs_info->flush_workers =
+ btrfs_alloc_workqueue("flush_delalloc", flags, max_active, 0);
+
+ fs_info->caching_workers =
+ btrfs_alloc_workqueue("cache", flags, max_active, 0);
+
+ /*
+ * a higher idle thresh on the submit workers makes it much more
+ * likely that bios will be send down in a sane order to the
+ * devices
+ */
+ fs_info->submit_workers =
+ btrfs_alloc_workqueue("submit", flags,
+ min_t(u64, fs_devices->num_devices,
+ max_active), 64);
+
+ fs_info->fixup_workers =
+ btrfs_alloc_workqueue("fixup", flags, 1, 0);
+
+ /*
+ * endios are largely parallel and should have a very
+ * low idle thresh
+ */
+ fs_info->endio_workers =
+ btrfs_alloc_workqueue("endio", flags, max_active, 4);
+ fs_info->endio_meta_workers =
+ btrfs_alloc_workqueue("endio-meta", flags, max_active, 4);
+ fs_info->endio_meta_write_workers =
+ btrfs_alloc_workqueue("endio-meta-write", flags, max_active, 2);
+ fs_info->endio_raid56_workers =
+ btrfs_alloc_workqueue("endio-raid56", flags, max_active, 4);
+ fs_info->endio_repair_workers =
+ btrfs_alloc_workqueue("endio-repair", flags, 1, 0);
+ fs_info->rmw_workers =
+ btrfs_alloc_workqueue("rmw", flags, max_active, 2);
+ fs_info->endio_write_workers =
+ btrfs_alloc_workqueue("endio-write", flags, max_active, 2);
+ fs_info->endio_freespace_worker =
+ btrfs_alloc_workqueue("freespace-write", flags, max_active, 0);
+ fs_info->delayed_workers =
+ btrfs_alloc_workqueue("delayed-meta", flags, max_active, 0);
+ fs_info->readahead_workers =
+ btrfs_alloc_workqueue("readahead", flags, max_active, 2);
+ fs_info->qgroup_rescan_workers =
+ btrfs_alloc_workqueue("qgroup-rescan", flags, 1, 0);
+ fs_info->extent_workers =
+ btrfs_alloc_workqueue("extent-refs", flags,
+ min_t(u64, fs_devices->num_devices,
+ max_active), 8);
+
+ if (!(fs_info->workers && fs_info->delalloc_workers &&
+ fs_info->submit_workers && fs_info->flush_workers &&
+ fs_info->endio_workers && fs_info->endio_meta_workers &&
+ fs_info->endio_meta_write_workers &&
+ fs_info->endio_repair_workers &&
+ fs_info->endio_write_workers && fs_info->endio_raid56_workers &&
+ fs_info->endio_freespace_worker && fs_info->rmw_workers &&
+ fs_info->caching_workers && fs_info->readahead_workers &&
+ fs_info->fixup_workers && fs_info->delayed_workers &&
+ fs_info->extent_workers &&
+ fs_info->qgroup_rescan_workers)) {
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
+ struct btrfs_fs_devices *fs_devices)
+{
+ int ret;
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ struct btrfs_root *log_tree_root;
+ struct btrfs_super_block *disk_super = fs_info->super_copy;
+ u64 bytenr = btrfs_super_log_root(disk_super);
+
+ if (fs_devices->rw_devices == 0) {
+ printk(KERN_WARNING "BTRFS: log replay required "
+ "on RO media\n");
+ return -EIO;
+ }
+
+ log_tree_root = btrfs_alloc_root(fs_info);
+ if (!log_tree_root)
+ return -ENOMEM;
+
+ __setup_root(tree_root->nodesize, tree_root->sectorsize,
+ tree_root->stripesize, log_tree_root, fs_info,
+ BTRFS_TREE_LOG_OBJECTID);
+
+ log_tree_root->node = read_tree_block(tree_root, bytenr,
+ fs_info->generation + 1);
+ if (!log_tree_root->node ||
+ !extent_buffer_uptodate(log_tree_root->node)) {
+ printk(KERN_ERR "BTRFS: failed to read log tree\n");
+ free_extent_buffer(log_tree_root->node);
+ kfree(log_tree_root);
+ return -EIO;
+ }
+ /* returns with log_tree_root freed on success */
+ ret = btrfs_recover_log_trees(log_tree_root);
+ if (ret) {
+ btrfs_error(tree_root->fs_info, ret,
+ "Failed to recover log tree");
+ free_extent_buffer(log_tree_root->node);
+ kfree(log_tree_root);
+ return ret;
+ }
+
+ if (fs_info->sb->s_flags & MS_RDONLY) {
+ ret = btrfs_commit_super(tree_root);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int btrfs_read_roots(struct btrfs_fs_info *fs_info,
+ struct btrfs_root *tree_root)
+{
+ struct btrfs_root *root;
+ struct btrfs_key location;
+ int ret;
+
+ location.objectid = BTRFS_EXTENT_TREE_OBJECTID;
+ location.type = BTRFS_ROOT_ITEM_KEY;
+ location.offset = 0;
+
+ root = btrfs_read_tree_root(tree_root, &location);
+ if (IS_ERR(root))
+ return PTR_ERR(root);
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->extent_root = root;
+
+ location.objectid = BTRFS_DEV_TREE_OBJECTID;
+ root = btrfs_read_tree_root(tree_root, &location);
+ if (IS_ERR(root))
+ return PTR_ERR(root);
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->dev_root = root;
+ btrfs_init_devices_late(fs_info);
+
+ location.objectid = BTRFS_CSUM_TREE_OBJECTID;
+ root = btrfs_read_tree_root(tree_root, &location);
+ if (IS_ERR(root))
+ return PTR_ERR(root);
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->csum_root = root;
+
+ location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
+ root = btrfs_read_tree_root(tree_root, &location);
+ if (!IS_ERR(root)) {
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->quota_enabled = 1;
+ fs_info->pending_quota_state = 1;
+ fs_info->quota_root = root;
+ }
+
+ location.objectid = BTRFS_UUID_TREE_OBJECTID;
+ root = btrfs_read_tree_root(tree_root, &location);
+ if (IS_ERR(root)) {
+ ret = PTR_ERR(root);
+ if (ret != -ENOENT)
+ return ret;
+ } else {
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->uuid_root = root;
+ }
+
+ return 0;
+}
+
+int open_ctree(struct super_block *sb,
+ struct btrfs_fs_devices *fs_devices,
+ char *options)
+{
+ u32 sectorsize;
+ u32 nodesize;
+ u32 stripesize;
+ u64 generation;
+ u64 features;
+ struct btrfs_key location;
+ struct buffer_head *bh;
+ struct btrfs_super_block *disk_super;
+ struct btrfs_fs_info *fs_info = btrfs_sb(sb);
+ struct btrfs_root *tree_root;
+ struct btrfs_root *chunk_root;
+ int ret;
+ int err = -EINVAL;
+ int num_backups_tried = 0;
+ int backup_index = 0;
+ int max_active;
+
+ tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info);
+ chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info);
+ if (!tree_root || !chunk_root) {
+ err = -ENOMEM;
+ goto fail;
+ }
+
+ ret = init_srcu_struct(&fs_info->subvol_srcu);
+ if (ret) {
+ err = ret;
+ goto fail;
+ }
+
+ ret = setup_bdi(fs_info, &fs_info->bdi);
+ if (ret) {
+ err = ret;
+ goto fail_srcu;
+ }
+
+ ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
+ if (ret) {
+ err = ret;
+ goto fail_bdi;
+ }
+ fs_info->dirty_metadata_batch = PAGE_CACHE_SIZE *
+ (1 + ilog2(nr_cpu_ids));
+
+ ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
+ if (ret) {
+ err = ret;
+ goto fail_dirty_metadata_bytes;
+ }
+
+ ret = percpu_counter_init(&fs_info->bio_counter, 0, GFP_KERNEL);
+ if (ret) {
+ err = ret;
+ goto fail_delalloc_bytes;
+ }
+
+ fs_info->btree_inode = new_inode(sb);
+ if (!fs_info->btree_inode) {
+ err = -ENOMEM;
+ goto fail_bio_counter;
+ }
+
+ mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
+
+ INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
+ INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
+ INIT_LIST_HEAD(&fs_info->trans_list);
+ INIT_LIST_HEAD(&fs_info->dead_roots);
+ INIT_LIST_HEAD(&fs_info->delayed_iputs);
+ INIT_LIST_HEAD(&fs_info->delalloc_roots);
+ INIT_LIST_HEAD(&fs_info->caching_block_groups);
+ spin_lock_init(&fs_info->delalloc_root_lock);
+ spin_lock_init(&fs_info->trans_lock);
+ spin_lock_init(&fs_info->fs_roots_radix_lock);
+ spin_lock_init(&fs_info->delayed_iput_lock);
+ spin_lock_init(&fs_info->defrag_inodes_lock);
+ spin_lock_init(&fs_info->free_chunk_lock);
+ spin_lock_init(&fs_info->tree_mod_seq_lock);
+ spin_lock_init(&fs_info->super_lock);
+ spin_lock_init(&fs_info->qgroup_op_lock);
+ spin_lock_init(&fs_info->buffer_lock);
+ spin_lock_init(&fs_info->unused_bgs_lock);
+ rwlock_init(&fs_info->tree_mod_log_lock);
+ mutex_init(&fs_info->unused_bg_unpin_mutex);
+ mutex_init(&fs_info->reloc_mutex);
+ mutex_init(&fs_info->delalloc_root_mutex);
+ seqlock_init(&fs_info->profiles_lock);
+ init_rwsem(&fs_info->delayed_iput_sem);
+
+ init_completion(&fs_info->kobj_unregister);
+ INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
+ INIT_LIST_HEAD(&fs_info->space_info);
+ INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
+ INIT_LIST_HEAD(&fs_info->unused_bgs);
+ btrfs_mapping_init(&fs_info->mapping_tree);
+ btrfs_init_block_rsv(&fs_info->global_block_rsv,
+ BTRFS_BLOCK_RSV_GLOBAL);
+ btrfs_init_block_rsv(&fs_info->delalloc_block_rsv,
+ BTRFS_BLOCK_RSV_DELALLOC);
+ btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
+ btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
+ btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
+ btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
+ BTRFS_BLOCK_RSV_DELOPS);
+ atomic_set(&fs_info->nr_async_submits, 0);
+ atomic_set(&fs_info->async_delalloc_pages, 0);
+ atomic_set(&fs_info->async_submit_draining, 0);
+ atomic_set(&fs_info->nr_async_bios, 0);
+ atomic_set(&fs_info->defrag_running, 0);
+ atomic_set(&fs_info->qgroup_op_seq, 0);
+ atomic64_set(&fs_info->tree_mod_seq, 0);
+ fs_info->sb = sb;
+ fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
+ fs_info->metadata_ratio = 0;
+ fs_info->defrag_inodes = RB_ROOT;
+ fs_info->free_chunk_space = 0;
+ fs_info->tree_mod_log = RB_ROOT;
+ fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
+ fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
+ /* readahead state */
+ INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
+ spin_lock_init(&fs_info->reada_lock);
+
+ fs_info->thread_pool_size = min_t(unsigned long,
+ num_online_cpus() + 2, 8);
+
+ INIT_LIST_HEAD(&fs_info->ordered_roots);
+ spin_lock_init(&fs_info->ordered_root_lock);
+ fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
+ GFP_NOFS);
+ if (!fs_info->delayed_root) {
+ err = -ENOMEM;
+ goto fail_iput;
+ }
+ btrfs_init_delayed_root(fs_info->delayed_root);
+
+ btrfs_init_scrub(fs_info);
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+ fs_info->check_integrity_print_mask = 0;
+#endif
+ btrfs_init_balance(fs_info);
+ btrfs_init_async_reclaim_work(&fs_info->async_reclaim_work);
+
+ sb->s_blocksize = 4096;
+ sb->s_blocksize_bits = blksize_bits(4096);
+ sb->s_bdi = &fs_info->bdi;
+
+ btrfs_init_btree_inode(fs_info, tree_root);
+
+ spin_lock_init(&fs_info->block_group_cache_lock);
+ fs_info->block_group_cache_tree = RB_ROOT;
+ fs_info->first_logical_byte = (u64)-1;
+
+ extent_io_tree_init(&fs_info->freed_extents[0],
+ fs_info->btree_inode->i_mapping);
+ extent_io_tree_init(&fs_info->freed_extents[1],
+ fs_info->btree_inode->i_mapping);
+ fs_info->pinned_extents = &fs_info->freed_extents[0];
+ fs_info->do_barriers = 1;
+
+
+ mutex_init(&fs_info->ordered_operations_mutex);
+ mutex_init(&fs_info->ordered_extent_flush_mutex);
+ mutex_init(&fs_info->tree_log_mutex);
+ mutex_init(&fs_info->chunk_mutex);
+ mutex_init(&fs_info->transaction_kthread_mutex);
+ mutex_init(&fs_info->cleaner_mutex);
+ mutex_init(&fs_info->volume_mutex);
+ mutex_init(&fs_info->ro_block_group_mutex);
+ init_rwsem(&fs_info->commit_root_sem);
+ init_rwsem(&fs_info->cleanup_work_sem);
+ init_rwsem(&fs_info->subvol_sem);
+ sema_init(&fs_info->uuid_tree_rescan_sem, 1);
+
+ btrfs_init_dev_replace_locks(fs_info);
+ btrfs_init_qgroup(fs_info);
+
+ btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
+ btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
+
+ init_waitqueue_head(&fs_info->transaction_throttle);
+ init_waitqueue_head(&fs_info->transaction_wait);
+ init_waitqueue_head(&fs_info->transaction_blocked_wait);
+ init_waitqueue_head(&fs_info->async_submit_wait);
+
+ INIT_LIST_HEAD(&fs_info->pinned_chunks);
+
+ ret = btrfs_alloc_stripe_hash_table(fs_info);
+ if (ret) {
+ err = ret;
+ goto fail_alloc;
+ }
+
+ __setup_root(4096, 4096, 4096, tree_root,
+ fs_info, BTRFS_ROOT_TREE_OBJECTID);
+
+ invalidate_bdev(fs_devices->latest_bdev);
+
+ /*
+ * Read super block and check the signature bytes only
+ */
+ bh = btrfs_read_dev_super(fs_devices->latest_bdev);
+ if (!bh) {
+ err = -EINVAL;
+ goto fail_alloc;
+ }
+
+ /*
+ * We want to check superblock checksum, the type is stored inside.
+ * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
+ */
+ if (btrfs_check_super_csum(bh->b_data)) {
+ printk(KERN_ERR "BTRFS: superblock checksum mismatch\n");
+ err = -EINVAL;
+ goto fail_alloc;
+ }
+
+ /*
+ * super_copy is zeroed at allocation time and we never touch the
+ * following bytes up to INFO_SIZE, the checksum is calculated from
+ * the whole block of INFO_SIZE
+ */
+ memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
+ memcpy(fs_info->super_for_commit, fs_info->super_copy,
+ sizeof(*fs_info->super_for_commit));
+ brelse(bh);
+
+ memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
+
+ ret = btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
+ if (ret) {
+ printk(KERN_ERR "BTRFS: superblock contains fatal errors\n");
+ err = -EINVAL;
+ goto fail_alloc;
+ }
+
+ disk_super = fs_info->super_copy;
+ if (!btrfs_super_root(disk_super))
+ goto fail_alloc;
+
+ /* check FS state, whether FS is broken. */
+ if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
+ set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
+
+ /*
+ * run through our array of backup supers and setup
+ * our ring pointer to the oldest one
+ */
+ generation = btrfs_super_generation(disk_super);
+ find_oldest_super_backup(fs_info, generation);
+
+ /*
+ * In the long term, we'll store the compression type in the super
+ * block, and it'll be used for per file compression control.
+ */
+ fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
+
+ ret = btrfs_parse_options(tree_root, options);
+ if (ret) {
+ err = ret;
+ goto fail_alloc;
+ }
+
+ features = btrfs_super_incompat_flags(disk_super) &
+ ~BTRFS_FEATURE_INCOMPAT_SUPP;
+ if (features) {
+ printk(KERN_ERR "BTRFS: couldn't mount because of "
+ "unsupported optional features (%Lx).\n",
+ features);
+ err = -EINVAL;
+ goto fail_alloc;
+ }
+
+ /*
+ * Leafsize and nodesize were always equal, this is only a sanity check.
+ */
+ if (le32_to_cpu(disk_super->__unused_leafsize) !=
+ btrfs_super_nodesize(disk_super)) {
+ printk(KERN_ERR "BTRFS: couldn't mount because metadata "
+ "blocksizes don't match. node %d leaf %d\n",
+ btrfs_super_nodesize(disk_super),
+ le32_to_cpu(disk_super->__unused_leafsize));
+ err = -EINVAL;
+ goto fail_alloc;
+ }
+ if (btrfs_super_nodesize(disk_super) > BTRFS_MAX_METADATA_BLOCKSIZE) {
+ printk(KERN_ERR "BTRFS: couldn't mount because metadata "
+ "blocksize (%d) was too large\n",
+ btrfs_super_nodesize(disk_super));
+ err = -EINVAL;
+ goto fail_alloc;
+ }
+
+ features = btrfs_super_incompat_flags(disk_super);
+ features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
+ if (tree_root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
+ features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
+
+ if (features & BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)
+ printk(KERN_INFO "BTRFS: has skinny extents\n");
+
+ /*
+ * flag our filesystem as having big metadata blocks if
+ * they are bigger than the page size
+ */
+ if (btrfs_super_nodesize(disk_super) > PAGE_CACHE_SIZE) {
+ if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
+ printk(KERN_INFO "BTRFS: flagging fs with big metadata feature\n");
+ features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
+ }
+
+ nodesize = btrfs_super_nodesize(disk_super);
+ sectorsize = btrfs_super_sectorsize(disk_super);
+ stripesize = btrfs_super_stripesize(disk_super);
+ fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
+ fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
+
+ /*
+ * mixed block groups end up with duplicate but slightly offset
+ * extent buffers for the same range. It leads to corruptions
+ */
+ if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
+ (sectorsize != nodesize)) {
+ printk(KERN_ERR "BTRFS: unequal leaf/node/sector sizes "
+ "are not allowed for mixed block groups on %s\n",
+ sb->s_id);
+ goto fail_alloc;
+ }
+
+ /*
+ * Needn't use the lock because there is no other task which will
+ * update the flag.
+ */
+ btrfs_set_super_incompat_flags(disk_super, features);
+
+ features = btrfs_super_compat_ro_flags(disk_super) &
+ ~BTRFS_FEATURE_COMPAT_RO_SUPP;
+ if (!(sb->s_flags & MS_RDONLY) && features) {
+ printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
+ "unsupported option features (%Lx).\n",
+ features);
+ err = -EINVAL;
+ goto fail_alloc;
+ }
+
+ max_active = fs_info->thread_pool_size;
+
+ ret = btrfs_init_workqueues(fs_info, fs_devices);
+ if (ret) {
+ err = ret;
+ goto fail_sb_buffer;
+ }
+
+ fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
+ fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
+ 4 * 1024 * 1024 / PAGE_CACHE_SIZE);
+
+ tree_root->nodesize = nodesize;
+ tree_root->sectorsize = sectorsize;
+ tree_root->stripesize = stripesize;
+
+ sb->s_blocksize = sectorsize;
+ sb->s_blocksize_bits = blksize_bits(sectorsize);
+
+ if (btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
+ printk(KERN_ERR "BTRFS: valid FS not found on %s\n", sb->s_id);
+ goto fail_sb_buffer;
+ }
+
+ if (sectorsize != PAGE_SIZE) {
+ printk(KERN_ERR "BTRFS: incompatible sector size (%lu) "
+ "found on %s\n", (unsigned long)sectorsize, sb->s_id);
+ goto fail_sb_buffer;
+ }
+
+ mutex_lock(&fs_info->chunk_mutex);
+ ret = btrfs_read_sys_array(tree_root);
+ mutex_unlock(&fs_info->chunk_mutex);
+ if (ret) {
+ printk(KERN_ERR "BTRFS: failed to read the system "
+ "array on %s\n", sb->s_id);
+ goto fail_sb_buffer;
+ }
+
+ generation = btrfs_super_chunk_root_generation(disk_super);
+
+ __setup_root(nodesize, sectorsize, stripesize, chunk_root,
+ fs_info, BTRFS_CHUNK_TREE_OBJECTID);
+
+ chunk_root->node = read_tree_block(chunk_root,
+ btrfs_super_chunk_root(disk_super),
+ generation);
+ if (!chunk_root->node ||
+ !test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
+ printk(KERN_ERR "BTRFS: failed to read chunk root on %s\n",
+ sb->s_id);
+ goto fail_tree_roots;
+ }
+ btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
+ chunk_root->commit_root = btrfs_root_node(chunk_root);
+
+ read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
+ btrfs_header_chunk_tree_uuid(chunk_root->node), BTRFS_UUID_SIZE);
+
+ ret = btrfs_read_chunk_tree(chunk_root);
+ if (ret) {
+ printk(KERN_ERR "BTRFS: failed to read chunk tree on %s\n",
+ sb->s_id);
+ goto fail_tree_roots;
+ }
+
+ /*
+ * keep the device that is marked to be the target device for the
+ * dev_replace procedure
+ */
+ btrfs_close_extra_devices(fs_devices, 0);
+
+ if (!fs_devices->latest_bdev) {
+ printk(KERN_ERR "BTRFS: failed to read devices on %s\n",
+ sb->s_id);
+ goto fail_tree_roots;
+ }
+
+retry_root_backup:
+ generation = btrfs_super_generation(disk_super);
+
+ tree_root->node = read_tree_block(tree_root,
+ btrfs_super_root(disk_super),
+ generation);
+ if (!tree_root->node ||
+ !test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
+ printk(KERN_WARNING "BTRFS: failed to read tree root on %s\n",
+ sb->s_id);
+
+ goto recovery_tree_root;
+ }
+
+ btrfs_set_root_node(&tree_root->root_item, tree_root->node);
+ tree_root->commit_root = btrfs_root_node(tree_root);
+ btrfs_set_root_refs(&tree_root->root_item, 1);
+
+ ret = btrfs_read_roots(fs_info, tree_root);
+ if (ret)
+ goto recovery_tree_root;
+
+ fs_info->generation = generation;
+ fs_info->last_trans_committed = generation;
+
+ ret = btrfs_recover_balance(fs_info);
+ if (ret) {
+ printk(KERN_ERR "BTRFS: failed to recover balance\n");
+ goto fail_block_groups;
+ }
+
+ ret = btrfs_init_dev_stats(fs_info);
+ if (ret) {
+ printk(KERN_ERR "BTRFS: failed to init dev_stats: %d\n",
+ ret);
+ goto fail_block_groups;
+ }
+
+ ret = btrfs_init_dev_replace(fs_info);
+ if (ret) {
+ pr_err("BTRFS: failed to init dev_replace: %d\n", ret);
+ goto fail_block_groups;
+ }
+
+ btrfs_close_extra_devices(fs_devices, 1);
+
+ ret = btrfs_sysfs_add_one(fs_info);
+ if (ret) {
+ pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
+ goto fail_block_groups;
+ }
+
+ ret = btrfs_init_space_info(fs_info);
+ if (ret) {
+ printk(KERN_ERR "BTRFS: Failed to initial space info: %d\n", ret);
+ goto fail_sysfs;
+ }
+
+ ret = btrfs_read_block_groups(fs_info->extent_root);
+ if (ret) {
+ printk(KERN_ERR "BTRFS: Failed to read block groups: %d\n", ret);
+ goto fail_sysfs;
+ }
+ fs_info->num_tolerated_disk_barrier_failures =
+ btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
+ if (fs_info->fs_devices->missing_devices >
+ fs_info->num_tolerated_disk_barrier_failures &&
+ !(sb->s_flags & MS_RDONLY)) {
+ printk(KERN_WARNING "BTRFS: "
+ "too many missing devices, writeable mount is not allowed\n");
+ goto fail_sysfs;
+ }
+
+ fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
+ "btrfs-cleaner");
+ if (IS_ERR(fs_info->cleaner_kthread))
+ goto fail_sysfs;
+
+ fs_info->transaction_kthread = kthread_run(transaction_kthread,
+ tree_root,
+ "btrfs-transaction");
+ if (IS_ERR(fs_info->transaction_kthread))
+ goto fail_cleaner;
+
+ if (!btrfs_test_opt(tree_root, SSD) &&
+ !btrfs_test_opt(tree_root, NOSSD) &&
+ !fs_info->fs_devices->rotating) {
+ printk(KERN_INFO "BTRFS: detected SSD devices, enabling SSD "
+ "mode\n");
+ btrfs_set_opt(fs_info->mount_opt, SSD);
+ }
+
+ /*
+ * Mount does not set all options immediatelly, we can do it now and do
+ * not have to wait for transaction commit
+ */
+ btrfs_apply_pending_changes(fs_info);
+
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+ if (btrfs_test_opt(tree_root, CHECK_INTEGRITY)) {
+ ret = btrfsic_mount(tree_root, fs_devices,
+ btrfs_test_opt(tree_root,
+ CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
+ 1 : 0,
+ fs_info->check_integrity_print_mask);
+ if (ret)
+ printk(KERN_WARNING "BTRFS: failed to initialize"
+ " integrity check module %s\n", sb->s_id);
+ }
+#endif
+ ret = btrfs_read_qgroup_config(fs_info);
+ if (ret)
+ goto fail_trans_kthread;
+
+ /* do not make disk changes in broken FS */
+ if (btrfs_super_log_root(disk_super) != 0) {
+ ret = btrfs_replay_log(fs_info, fs_devices);
+ if (ret) {
+ err = ret;
+ goto fail_qgroup;
+ }
+ }
+
+ ret = btrfs_find_orphan_roots(tree_root);
+ if (ret)
+ goto fail_qgroup;
+
+ if (!(sb->s_flags & MS_RDONLY)) {
+ ret = btrfs_cleanup_fs_roots(fs_info);
+ if (ret)
+ goto fail_qgroup;
+
+ mutex_lock(&fs_info->cleaner_mutex);
+ ret = btrfs_recover_relocation(tree_root);
+ mutex_unlock(&fs_info->cleaner_mutex);
+ if (ret < 0) {
+ printk(KERN_WARNING
+ "BTRFS: failed to recover relocation\n");
+ err = -EINVAL;
+ goto fail_qgroup;
+ }
+ }
+
+ location.objectid = BTRFS_FS_TREE_OBJECTID;
+ location.type = BTRFS_ROOT_ITEM_KEY;
+ location.offset = 0;
+
+ fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
+ if (IS_ERR(fs_info->fs_root)) {
+ err = PTR_ERR(fs_info->fs_root);
+ goto fail_qgroup;
+ }
+
+ if (sb->s_flags & MS_RDONLY)
+ return 0;
+
+ down_read(&fs_info->cleanup_work_sem);
+ if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
+ (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
+ up_read(&fs_info->cleanup_work_sem);
+ close_ctree(tree_root);
+ return ret;
+ }
+ up_read(&fs_info->cleanup_work_sem);
+
+ ret = btrfs_resume_balance_async(fs_info);
+ if (ret) {
+ printk(KERN_WARNING "BTRFS: failed to resume balance\n");
+ close_ctree(tree_root);
+ return ret;
+ }
+
+ ret = btrfs_resume_dev_replace_async(fs_info);
+ if (ret) {
+ pr_warn("BTRFS: failed to resume dev_replace\n");
+ close_ctree(tree_root);
+ return ret;
+ }
+
+ btrfs_qgroup_rescan_resume(fs_info);
+
+ if (!fs_info->uuid_root) {
+ pr_info("BTRFS: creating UUID tree\n");
+ ret = btrfs_create_uuid_tree(fs_info);
+ if (ret) {
+ pr_warn("BTRFS: failed to create the UUID tree %d\n",
+ ret);
+ close_ctree(tree_root);
+ return ret;
+ }
+ } else if (btrfs_test_opt(tree_root, RESCAN_UUID_TREE) ||
+ fs_info->generation !=
+ btrfs_super_uuid_tree_generation(disk_super)) {
+ pr_info("BTRFS: checking UUID tree\n");
+ ret = btrfs_check_uuid_tree(fs_info);
+ if (ret) {
+ pr_warn("BTRFS: failed to check the UUID tree %d\n",
+ ret);
+ close_ctree(tree_root);
+ return ret;
+ }
+ } else {
+ fs_info->update_uuid_tree_gen = 1;
+ }
+
+ fs_info->open = 1;
+
+ return 0;
+
+fail_qgroup:
+ btrfs_free_qgroup_config(fs_info);
+fail_trans_kthread:
+ kthread_stop(fs_info->transaction_kthread);
+ btrfs_cleanup_transaction(fs_info->tree_root);
+ btrfs_free_fs_roots(fs_info);
+fail_cleaner:
+ kthread_stop(fs_info->cleaner_kthread);
+
+ /*
+ * make sure we're done with the btree inode before we stop our
+ * kthreads
+ */
+ filemap_write_and_wait(fs_info->btree_inode->i_mapping);
+
+fail_sysfs:
+ btrfs_sysfs_remove_one(fs_info);
+
+fail_block_groups:
+ btrfs_put_block_group_cache(fs_info);
+ btrfs_free_block_groups(fs_info);
+
+fail_tree_roots:
+ free_root_pointers(fs_info, 1);
+ invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
+
+fail_sb_buffer:
+ btrfs_stop_all_workers(fs_info);
+fail_alloc:
+fail_iput:
+ btrfs_mapping_tree_free(&fs_info->mapping_tree);
+
+ iput(fs_info->btree_inode);
+fail_bio_counter:
+ percpu_counter_destroy(&fs_info->bio_counter);
+fail_delalloc_bytes:
+ percpu_counter_destroy(&fs_info->delalloc_bytes);
+fail_dirty_metadata_bytes:
+ percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
+fail_bdi:
+ bdi_destroy(&fs_info->bdi);
+fail_srcu:
+ cleanup_srcu_struct(&fs_info->subvol_srcu);
+fail:
+ btrfs_free_stripe_hash_table(fs_info);
+ btrfs_close_devices(fs_info->fs_devices);
+ return err;
+
+recovery_tree_root:
+ if (!btrfs_test_opt(tree_root, RECOVERY))
+ goto fail_tree_roots;
+
+ free_root_pointers(fs_info, 0);
+
+ /* don't use the log in recovery mode, it won't be valid */
+ btrfs_set_super_log_root(disk_super, 0);
+
+ /* we can't trust the free space cache either */
+ btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
+
+ ret = next_root_backup(fs_info, fs_info->super_copy,
+ &num_backups_tried, &backup_index);
+ if (ret == -1)
+ goto fail_block_groups;
+ goto retry_root_backup;
+}
+
+static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
+{
+ if (uptodate) {
+ set_buffer_uptodate(bh);
+ } else {
+ struct btrfs_device *device = (struct btrfs_device *)
+ bh->b_private;
+
+ printk_ratelimited_in_rcu(KERN_WARNING "BTRFS: lost page write due to "
+ "I/O error on %s\n",
+ rcu_str_deref(device->name));
+ /* note, we dont' set_buffer_write_io_error because we have
+ * our own ways of dealing with the IO errors
+ */
+ clear_buffer_uptodate(bh);
+ btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_WRITE_ERRS);
+ }
+ unlock_buffer(bh);
+ put_bh(bh);
+}
+
+struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
+{
+ struct buffer_head *bh;
+ struct buffer_head *latest = NULL;
+ struct btrfs_super_block *super;
+ int i;
+ u64 transid = 0;
+ u64 bytenr;
+
+ /* we would like to check all the supers, but that would make
+ * a btrfs mount succeed after a mkfs from a different FS.
+ * So, we need to add a special mount option to scan for
+ * later supers, using BTRFS_SUPER_MIRROR_MAX instead
+ */
+ for (i = 0; i < 1; i++) {
+ bytenr = btrfs_sb_offset(i);
+ if (bytenr + BTRFS_SUPER_INFO_SIZE >=
+ i_size_read(bdev->bd_inode))
+ break;
+ bh = __bread(bdev, bytenr / 4096,
+ BTRFS_SUPER_INFO_SIZE);
+ if (!bh)
+ continue;
+
+ super = (struct btrfs_super_block *)bh->b_data;
+ if (btrfs_super_bytenr(super) != bytenr ||
+ btrfs_super_magic(super) != BTRFS_MAGIC) {
+ brelse(bh);
+ continue;
+ }
+
+ if (!latest || btrfs_super_generation(super) > transid) {
+ brelse(latest);
+ latest = bh;
+ transid = btrfs_super_generation(super);
+ } else {
+ brelse(bh);
+ }
+ }
+ return latest;
+}
+
+/*
+ * this should be called twice, once with wait == 0 and
+ * once with wait == 1. When wait == 0 is done, all the buffer heads
+ * we write are pinned.
+ *
+ * They are released when wait == 1 is done.
+ * max_mirrors must be the same for both runs, and it indicates how
+ * many supers on this one device should be written.
+ *
+ * max_mirrors == 0 means to write them all.
+ */
+static int write_dev_supers(struct btrfs_device *device,
+ struct btrfs_super_block *sb,
+ int do_barriers, int wait, int max_mirrors)
+{
+ struct buffer_head *bh;
+ int i;
+ int ret;
+ int errors = 0;
+ u32 crc;
+ u64 bytenr;
+
+ if (max_mirrors == 0)
+ max_mirrors = BTRFS_SUPER_MIRROR_MAX;
+
+ for (i = 0; i < max_mirrors; i++) {
+ bytenr = btrfs_sb_offset(i);
+ if (bytenr + BTRFS_SUPER_INFO_SIZE >=
+ device->commit_total_bytes)
+ break;
+
+ if (wait) {
+ bh = __find_get_block(device->bdev, bytenr / 4096,
+ BTRFS_SUPER_INFO_SIZE);
+ if (!bh) {
+ errors++;
+ continue;
+ }
+ wait_on_buffer(bh);
+ if (!buffer_uptodate(bh))
+ errors++;
+
+ /* drop our reference */
+ brelse(bh);
+
+ /* drop the reference from the wait == 0 run */
+ brelse(bh);
+ continue;
+ } else {
+ btrfs_set_super_bytenr(sb, bytenr);
+
+ crc = ~(u32)0;
+ crc = btrfs_csum_data((char *)sb +
+ BTRFS_CSUM_SIZE, crc,
+ BTRFS_SUPER_INFO_SIZE -
+ BTRFS_CSUM_SIZE);
+ btrfs_csum_final(crc, sb->csum);
+
+ /*
+ * one reference for us, and we leave it for the
+ * caller
+ */
+ bh = __getblk(device->bdev, bytenr / 4096,
+ BTRFS_SUPER_INFO_SIZE);
+ if (!bh) {
+ printk(KERN_ERR "BTRFS: couldn't get super "
+ "buffer head for bytenr %Lu\n", bytenr);
+ errors++;
+ continue;
+ }
+
+ memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
+
+ /* one reference for submit_bh */
+ get_bh(bh);
+
+ set_buffer_uptodate(bh);
+ lock_buffer(bh);
+ bh->b_end_io = btrfs_end_buffer_write_sync;
+ bh->b_private = device;
+ }
+
+ /*
+ * we fua the first super. The others we allow
+ * to go down lazy.
+ */
+ if (i == 0)
+ ret = btrfsic_submit_bh(WRITE_FUA, bh);
+ else
+ ret = btrfsic_submit_bh(WRITE_SYNC, bh);
+ if (ret)
+ errors++;
+ }
+ return errors < i ? 0 : -1;
+}
+
+/*
+ * endio for the write_dev_flush, this will wake anyone waiting
+ * for the barrier when it is done
+ */
+static void btrfs_end_empty_barrier(struct bio *bio, int err)
+{
+ if (err) {
+ if (err == -EOPNOTSUPP)
+ set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
+ clear_bit(BIO_UPTODATE, &bio->bi_flags);
+ }
+ if (bio->bi_private)
+ complete(bio->bi_private);
+ bio_put(bio);
+}
+
+/*
+ * trigger flushes for one the devices. If you pass wait == 0, the flushes are
+ * sent down. With wait == 1, it waits for the previous flush.
+ *
+ * any device where the flush fails with eopnotsupp are flagged as not-barrier
+ * capable
+ */
+static int write_dev_flush(struct btrfs_device *device, int wait)
+{
+ struct bio *bio;
+ int ret = 0;
+
+ if (device->nobarriers)
+ return 0;
+
+ if (wait) {
+ bio = device->flush_bio;
+ if (!bio)
+ return 0;
+
+ wait_for_completion(&device->flush_wait);
+
+ if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
+ printk_in_rcu("BTRFS: disabling barriers on dev %s\n",
+ rcu_str_deref(device->name));
+ device->nobarriers = 1;
+ } else if (!bio_flagged(bio, BIO_UPTODATE)) {
+ ret = -EIO;
+ btrfs_dev_stat_inc_and_print(device,
+ BTRFS_DEV_STAT_FLUSH_ERRS);
+ }
+
+ /* drop the reference from the wait == 0 run */
+ bio_put(bio);
+ device->flush_bio = NULL;
+
+ return ret;
+ }
+
+ /*
+ * one reference for us, and we leave it for the
+ * caller
+ */
+ device->flush_bio = NULL;
+ bio = btrfs_io_bio_alloc(GFP_NOFS, 0);
+ if (!bio)
+ return -ENOMEM;
+
+ bio->bi_end_io = btrfs_end_empty_barrier;
+ bio->bi_bdev = device->bdev;
+ init_completion(&device->flush_wait);
+ bio->bi_private = &device->flush_wait;
+ device->flush_bio = bio;
+
+ bio_get(bio);
+ btrfsic_submit_bio(WRITE_FLUSH, bio);
+
+ return 0;
+}
+
+/*
+ * send an empty flush down to each device in parallel,
+ * then wait for them
+ */
+static int barrier_all_devices(struct btrfs_fs_info *info)
+{
+ struct list_head *head;
+ struct btrfs_device *dev;
+ int errors_send = 0;
+ int errors_wait = 0;
+ int ret;
+
+ /* send down all the barriers */
+ head = &info->fs_devices->devices;
+ list_for_each_entry_rcu(dev, head, dev_list) {
+ if (dev->missing)
+ continue;
+ if (!dev->bdev) {
+ errors_send++;
+ continue;
+ }
+ if (!dev->in_fs_metadata || !dev->writeable)
+ continue;
+
+ ret = write_dev_flush(dev, 0);
+ if (ret)
+ errors_send++;
+ }
+
+ /* wait for all the barriers */
+ list_for_each_entry_rcu(dev, head, dev_list) {
+ if (dev->missing)
+ continue;
+ if (!dev->bdev) {
+ errors_wait++;
+ continue;
+ }
+ if (!dev->in_fs_metadata || !dev->writeable)
+ continue;
+
+ ret = write_dev_flush(dev, 1);
+ if (ret)
+ errors_wait++;
+ }
+ if (errors_send > info->num_tolerated_disk_barrier_failures ||
+ errors_wait > info->num_tolerated_disk_barrier_failures)
+ return -EIO;
+ return 0;
+}
+
+int btrfs_calc_num_tolerated_disk_barrier_failures(
+ struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_ioctl_space_info space;
+ struct btrfs_space_info *sinfo;
+ u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
+ BTRFS_BLOCK_GROUP_SYSTEM,
+ BTRFS_BLOCK_GROUP_METADATA,
+ BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
+ int num_types = 4;
+ int i;
+ int c;
+ int num_tolerated_disk_barrier_failures =
+ (int)fs_info->fs_devices->num_devices;
+
+ for (i = 0; i < num_types; i++) {
+ struct btrfs_space_info *tmp;
+
+ sinfo = NULL;
+ rcu_read_lock();
+ list_for_each_entry_rcu(tmp, &fs_info->space_info, list) {
+ if (tmp->flags == types[i]) {
+ sinfo = tmp;
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ if (!sinfo)
+ continue;
+
+ down_read(&sinfo->groups_sem);
+ for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
+ if (!list_empty(&sinfo->block_groups[c])) {
+ u64 flags;
+
+ btrfs_get_block_group_info(
+ &sinfo->block_groups[c], &space);
+ if (space.total_bytes == 0 ||
+ space.used_bytes == 0)
+ continue;
+ flags = space.flags;
+ /*
+ * return
+ * 0: if dup, single or RAID0 is configured for
+ * any of metadata, system or data, else
+ * 1: if RAID5 is configured, or if RAID1 or
+ * RAID10 is configured and only two mirrors
+ * are used, else
+ * 2: if RAID6 is configured, else
+ * num_mirrors - 1: if RAID1 or RAID10 is
+ * configured and more than
+ * 2 mirrors are used.
+ */
+ if (num_tolerated_disk_barrier_failures > 0 &&
+ ((flags & (BTRFS_BLOCK_GROUP_DUP |
+ BTRFS_BLOCK_GROUP_RAID0)) ||
+ ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK)
+ == 0)))
+ num_tolerated_disk_barrier_failures = 0;
+ else if (num_tolerated_disk_barrier_failures > 1) {
+ if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
+ BTRFS_BLOCK_GROUP_RAID5 |
+ BTRFS_BLOCK_GROUP_RAID10)) {
+ num_tolerated_disk_barrier_failures = 1;
+ } else if (flags &
+ BTRFS_BLOCK_GROUP_RAID6) {
+ num_tolerated_disk_barrier_failures = 2;
+ }
+ }
+ }
+ }
+ up_read(&sinfo->groups_sem);
+ }
+
+ return num_tolerated_disk_barrier_failures;
+}
+
+static int write_all_supers(struct btrfs_root *root, int max_mirrors)
+{
+ struct list_head *head;
+ struct btrfs_device *dev;
+ struct btrfs_super_block *sb;
+ struct btrfs_dev_item *dev_item;
+ int ret;
+ int do_barriers;
+ int max_errors;
+ int total_errors = 0;
+ u64 flags;
+
+ do_barriers = !btrfs_test_opt(root, NOBARRIER);
+ backup_super_roots(root->fs_info);
+
+ sb = root->fs_info->super_for_commit;
+ dev_item = &sb->dev_item;
+
+ mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
+ head = &root->fs_info->fs_devices->devices;
+ max_errors = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
+
+ if (do_barriers) {
+ ret = barrier_all_devices(root->fs_info);
+ if (ret) {
+ mutex_unlock(
+ &root->fs_info->fs_devices->device_list_mutex);
+ btrfs_error(root->fs_info, ret,
+ "errors while submitting device barriers.");
+ return ret;
+ }
+ }
+
+ list_for_each_entry_rcu(dev, head, dev_list) {
+ if (!dev->bdev) {
+ total_errors++;
+ continue;
+ }
+ if (!dev->in_fs_metadata || !dev->writeable)
+ continue;
+
+ btrfs_set_stack_device_generation(dev_item, 0);
+ btrfs_set_stack_device_type(dev_item, dev->type);
+ btrfs_set_stack_device_id(dev_item, dev->devid);
+ btrfs_set_stack_device_total_bytes(dev_item,
+ dev->commit_total_bytes);
+ btrfs_set_stack_device_bytes_used(dev_item,
+ dev->commit_bytes_used);
+ btrfs_set_stack_device_io_align(dev_item, dev->io_align);
+ btrfs_set_stack_device_io_width(dev_item, dev->io_width);
+ btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
+ memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
+ memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
+
+ flags = btrfs_super_flags(sb);
+ btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
+
+ ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
+ if (ret)
+ total_errors++;
+ }
+ if (total_errors > max_errors) {
+ btrfs_err(root->fs_info, "%d errors while writing supers",
+ total_errors);
+ mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
+
+ /* FUA is masked off if unsupported and can't be the reason */
+ btrfs_error(root->fs_info, -EIO,
+ "%d errors while writing supers", total_errors);
+ return -EIO;
+ }
+
+ total_errors = 0;
+ list_for_each_entry_rcu(dev, head, dev_list) {
+ if (!dev->bdev)
+ continue;
+ if (!dev->in_fs_metadata || !dev->writeable)
+ continue;
+
+ ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
+ if (ret)
+ total_errors++;
+ }
+ mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
+ if (total_errors > max_errors) {
+ btrfs_error(root->fs_info, -EIO,
+ "%d errors while writing supers", total_errors);
+ return -EIO;
+ }
+ return 0;
+}
+
+int write_ctree_super(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, int max_mirrors)
+{
+ return write_all_supers(root, max_mirrors);
+}
+
+/* Drop a fs root from the radix tree and free it. */
+void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
+ struct btrfs_root *root)
+{
+ spin_lock(&fs_info->fs_roots_radix_lock);
+ radix_tree_delete(&fs_info->fs_roots_radix,
+ (unsigned long)root->root_key.objectid);
+ spin_unlock(&fs_info->fs_roots_radix_lock);
+
+ if (btrfs_root_refs(&root->root_item) == 0)
+ synchronize_srcu(&fs_info->subvol_srcu);
+
+ if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
+ btrfs_free_log(NULL, root);
+
+ if (root->free_ino_pinned)
+ __btrfs_remove_free_space_cache(root->free_ino_pinned);
+ if (root->free_ino_ctl)
+ __btrfs_remove_free_space_cache(root->free_ino_ctl);
+ free_fs_root(root);
+}
+
+static void free_fs_root(struct btrfs_root *root)
+{
+ iput(root->ino_cache_inode);
+ WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
+ btrfs_free_block_rsv(root, root->orphan_block_rsv);
+ root->orphan_block_rsv = NULL;
+ if (root->anon_dev)
+ free_anon_bdev(root->anon_dev);
+ if (root->subv_writers)
+ btrfs_free_subvolume_writers(root->subv_writers);
+ free_extent_buffer(root->node);
+ free_extent_buffer(root->commit_root);
+ kfree(root->free_ino_ctl);
+ kfree(root->free_ino_pinned);
+ kfree(root->name);
+ btrfs_put_fs_root(root);
+}
+
+void btrfs_free_fs_root(struct btrfs_root *root)
+{
+ free_fs_root(root);
+}
+
+int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
+{
+ u64 root_objectid = 0;
+ struct btrfs_root *gang[8];
+ int i = 0;
+ int err = 0;
+ unsigned int ret = 0;
+ int index;
+
+ while (1) {
+ index = srcu_read_lock(&fs_info->subvol_srcu);
+ ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
+ (void **)gang, root_objectid,
+ ARRAY_SIZE(gang));
+ if (!ret) {
+ srcu_read_unlock(&fs_info->subvol_srcu, index);
+ break;
+ }
+ root_objectid = gang[ret - 1]->root_key.objectid + 1;
+
+ for (i = 0; i < ret; i++) {
+ /* Avoid to grab roots in dead_roots */
+ if (btrfs_root_refs(&gang[i]->root_item) == 0) {
+ gang[i] = NULL;
+ continue;
+ }
+ /* grab all the search result for later use */
+ gang[i] = btrfs_grab_fs_root(gang[i]);
+ }
+ srcu_read_unlock(&fs_info->subvol_srcu, index);
+
+ for (i = 0; i < ret; i++) {
+ if (!gang[i])
+ continue;
+ root_objectid = gang[i]->root_key.objectid;
+ err = btrfs_orphan_cleanup(gang[i]);
+ if (err)
+ break;
+ btrfs_put_fs_root(gang[i]);
+ }
+ root_objectid++;
+ }
+
+ /* release the uncleaned roots due to error */
+ for (; i < ret; i++) {
+ if (gang[i])
+ btrfs_put_fs_root(gang[i]);
+ }
+ return err;
+}
+
+int btrfs_commit_super(struct btrfs_root *root)
+{
+ struct btrfs_trans_handle *trans;
+
+ mutex_lock(&root->fs_info->cleaner_mutex);
+ btrfs_run_delayed_iputs(root);
+ mutex_unlock(&root->fs_info->cleaner_mutex);
+ wake_up_process(root->fs_info->cleaner_kthread);
+
+ /* wait until ongoing cleanup work done */
+ down_write(&root->fs_info->cleanup_work_sem);
+ up_write(&root->fs_info->cleanup_work_sem);
+
+ trans = btrfs_join_transaction(root);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+ return btrfs_commit_transaction(trans, root);
+}
+
+void close_ctree(struct btrfs_root *root)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ int ret;
+
+ fs_info->closing = 1;
+ smp_mb();
+
+ /* wait for the uuid_scan task to finish */
+ down(&fs_info->uuid_tree_rescan_sem);
+ /* avoid complains from lockdep et al., set sem back to initial state */
+ up(&fs_info->uuid_tree_rescan_sem);
+
+ /* pause restriper - we want to resume on mount */
+ btrfs_pause_balance(fs_info);
+
+ btrfs_dev_replace_suspend_for_unmount(fs_info);
+
+ btrfs_scrub_cancel(fs_info);
+
+ /* wait for any defraggers to finish */
+ wait_event(fs_info->transaction_wait,
+ (atomic_read(&fs_info->defrag_running) == 0));
+
+ /* clear out the rbtree of defraggable inodes */
+ btrfs_cleanup_defrag_inodes(fs_info);
+
+ cancel_work_sync(&fs_info->async_reclaim_work);
+
+ if (!(fs_info->sb->s_flags & MS_RDONLY)) {
+ ret = btrfs_commit_super(root);
+ if (ret)
+ btrfs_err(fs_info, "commit super ret %d", ret);
+ }
+
+ if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
+ btrfs_error_commit_super(root);
+
+ kthread_stop(fs_info->transaction_kthread);
+ kthread_stop(fs_info->cleaner_kthread);
+
+ fs_info->closing = 2;
+ smp_mb();
+
+ btrfs_free_qgroup_config(fs_info);
+
+ if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
+ btrfs_info(fs_info, "at unmount delalloc count %lld",
+ percpu_counter_sum(&fs_info->delalloc_bytes));
+ }
+
+ btrfs_sysfs_remove_one(fs_info);
+
+ btrfs_free_fs_roots(fs_info);
+
+ btrfs_put_block_group_cache(fs_info);
+
+ btrfs_free_block_groups(fs_info);
+
+ /*
+ * we must make sure there is not any read request to
+ * submit after we stopping all workers.
+ */
+ invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
+ btrfs_stop_all_workers(fs_info);
+
+ fs_info->open = 0;
+ free_root_pointers(fs_info, 1);
+
+ iput(fs_info->btree_inode);
+
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+ if (btrfs_test_opt(root, CHECK_INTEGRITY))
+ btrfsic_unmount(root, fs_info->fs_devices);
+#endif
+
+ btrfs_close_devices(fs_info->fs_devices);
+ btrfs_mapping_tree_free(&fs_info->mapping_tree);
+
+ percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
+ percpu_counter_destroy(&fs_info->delalloc_bytes);
+ percpu_counter_destroy(&fs_info->bio_counter);
+ bdi_destroy(&fs_info->bdi);
+ cleanup_srcu_struct(&fs_info->subvol_srcu);
+
+ btrfs_free_stripe_hash_table(fs_info);
+
+ __btrfs_free_block_rsv(root->orphan_block_rsv);
+ root->orphan_block_rsv = NULL;
+
+ lock_chunks(root);
+ while (!list_empty(&fs_info->pinned_chunks)) {
+ struct extent_map *em;
+
+ em = list_first_entry(&fs_info->pinned_chunks,
+ struct extent_map, list);
+ list_del_init(&em->list);
+ free_extent_map(em);
+ }
+ unlock_chunks(root);
+}
+
+int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
+ int atomic)
+{
+ int ret;
+ struct inode *btree_inode = buf->pages[0]->mapping->host;
+
+ ret = extent_buffer_uptodate(buf);
+ if (!ret)
+ return ret;
+
+ ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
+ parent_transid, atomic);
+ if (ret == -EAGAIN)
+ return ret;
+ return !ret;
+}
+
+int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
+{
+ return set_extent_buffer_uptodate(buf);
+}
+
+void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
+{
+ struct btrfs_root *root;
+ u64 transid = btrfs_header_generation(buf);
+ int was_dirty;
+
+#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
+ /*
+ * This is a fast path so only do this check if we have sanity tests
+ * enabled. Normal people shouldn't be marking dummy buffers as dirty
+ * outside of the sanity tests.
+ */
+ if (unlikely(test_bit(EXTENT_BUFFER_DUMMY, &buf->bflags)))
+ return;
+#endif
+ root = BTRFS_I(buf->pages[0]->mapping->host)->root;
+ btrfs_assert_tree_locked(buf);
+ if (transid != root->fs_info->generation)
+ WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, "
+ "found %llu running %llu\n",
+ buf->start, transid, root->fs_info->generation);
+ was_dirty = set_extent_buffer_dirty(buf);
+ if (!was_dirty)
+ __percpu_counter_add(&root->fs_info->dirty_metadata_bytes,
+ buf->len,
+ root->fs_info->dirty_metadata_batch);
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+ if (btrfs_header_level(buf) == 0 && check_leaf(root, buf)) {
+ btrfs_print_leaf(root, buf);
+ ASSERT(0);
+ }
+#endif
+}
+
+static void __btrfs_btree_balance_dirty(struct btrfs_root *root,
+ int flush_delayed)
+{
+ /*
+ * looks as though older kernels can get into trouble with
+ * this code, they end up stuck in balance_dirty_pages forever
+ */
+ int ret;
+
+ if (current->flags & PF_MEMALLOC)
+ return;
+
+ if (flush_delayed)
+ btrfs_balance_delayed_items(root);
+
+ ret = percpu_counter_compare(&root->fs_info->dirty_metadata_bytes,
+ BTRFS_DIRTY_METADATA_THRESH);
+ if (ret > 0) {
+ balance_dirty_pages_ratelimited(
+ root->fs_info->btree_inode->i_mapping);
+ }
+ return;
+}
+
+void btrfs_btree_balance_dirty(struct btrfs_root *root)
+{
+ __btrfs_btree_balance_dirty(root, 1);
+}
+
+void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root)
+{
+ __btrfs_btree_balance_dirty(root, 0);
+}
+
+int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
+{
+ struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
+ return btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
+}
+
+static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
+ int read_only)
+{
+ struct btrfs_super_block *sb = fs_info->super_copy;
+ int ret = 0;
+
+ if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
+ printk(KERN_ERR "BTRFS: tree_root level too big: %d >= %d\n",
+ btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
+ ret = -EINVAL;
+ }
+ if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
+ printk(KERN_ERR "BTRFS: chunk_root level too big: %d >= %d\n",
+ btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
+ ret = -EINVAL;
+ }
+ if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
+ printk(KERN_ERR "BTRFS: log_root level too big: %d >= %d\n",
+ btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
+ ret = -EINVAL;
+ }
+
+ /*
+ * The common minimum, we don't know if we can trust the nodesize/sectorsize
+ * items yet, they'll be verified later. Issue just a warning.
+ */
+ if (!IS_ALIGNED(btrfs_super_root(sb), 4096))
+ printk(KERN_WARNING "BTRFS: tree_root block unaligned: %llu\n",
+ btrfs_super_root(sb));
+ if (!IS_ALIGNED(btrfs_super_chunk_root(sb), 4096))
+ printk(KERN_WARNING "BTRFS: chunk_root block unaligned: %llu\n",
+ btrfs_super_chunk_root(sb));
+ if (!IS_ALIGNED(btrfs_super_log_root(sb), 4096))
+ printk(KERN_WARNING "BTRFS: log_root block unaligned: %llu\n",
+ btrfs_super_log_root(sb));
+
+ /*
+ * Check the lower bound, the alignment and other constraints are
+ * checked later.
+ */
+ if (btrfs_super_nodesize(sb) < 4096) {
+ printk(KERN_ERR "BTRFS: nodesize too small: %u < 4096\n",
+ btrfs_super_nodesize(sb));
+ ret = -EINVAL;
+ }
+ if (btrfs_super_sectorsize(sb) < 4096) {
+ printk(KERN_ERR "BTRFS: sectorsize too small: %u < 4096\n",
+ btrfs_super_sectorsize(sb));
+ ret = -EINVAL;
+ }
+
+ if (memcmp(fs_info->fsid, sb->dev_item.fsid, BTRFS_UUID_SIZE) != 0) {
+ printk(KERN_ERR "BTRFS: dev_item UUID does not match fsid: %pU != %pU\n",
+ fs_info->fsid, sb->dev_item.fsid);
+ ret = -EINVAL;
+ }
+
+ /*
+ * Hint to catch really bogus numbers, bitflips or so, more exact checks are
+ * done later
+ */
+ if (btrfs_super_num_devices(sb) > (1UL << 31))
+ printk(KERN_WARNING "BTRFS: suspicious number of devices: %llu\n",
+ btrfs_super_num_devices(sb));
+ if (btrfs_super_num_devices(sb) == 0) {
+ printk(KERN_ERR "BTRFS: number of devices is 0\n");
+ ret = -EINVAL;
+ }
+
+ if (btrfs_super_bytenr(sb) != BTRFS_SUPER_INFO_OFFSET) {
+ printk(KERN_ERR "BTRFS: super offset mismatch %llu != %u\n",
+ btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
+ ret = -EINVAL;
+ }
+
+ /*
+ * Obvious sys_chunk_array corruptions, it must hold at least one key
+ * and one chunk
+ */
+ if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
+ printk(KERN_ERR "BTRFS: system chunk array too big %u > %u\n",
+ btrfs_super_sys_array_size(sb),
+ BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
+ ret = -EINVAL;
+ }
+ if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
+ + sizeof(struct btrfs_chunk)) {
+ printk(KERN_ERR "BTRFS: system chunk array too small %u < %zu\n",
+ btrfs_super_sys_array_size(sb),
+ sizeof(struct btrfs_disk_key)
+ + sizeof(struct btrfs_chunk));
+ ret = -EINVAL;
+ }
+
+ /*
+ * The generation is a global counter, we'll trust it more than the others
+ * but it's still possible that it's the one that's wrong.
+ */
+ if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
+ printk(KERN_WARNING
+ "BTRFS: suspicious: generation < chunk_root_generation: %llu < %llu\n",
+ btrfs_super_generation(sb), btrfs_super_chunk_root_generation(sb));
+ if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
+ && btrfs_super_cache_generation(sb) != (u64)-1)
+ printk(KERN_WARNING
+ "BTRFS: suspicious: generation < cache_generation: %llu < %llu\n",
+ btrfs_super_generation(sb), btrfs_super_cache_generation(sb));
+
+ return ret;
+}
+
+static void btrfs_error_commit_super(struct btrfs_root *root)
+{
+ mutex_lock(&root->fs_info->cleaner_mutex);
+ btrfs_run_delayed_iputs(root);
+ mutex_unlock(&root->fs_info->cleaner_mutex);
+
+ down_write(&root->fs_info->cleanup_work_sem);
+ up_write(&root->fs_info->cleanup_work_sem);
+
+ /* cleanup FS via transaction */
+ btrfs_cleanup_transaction(root);
+}
+
+static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
+{
+ struct btrfs_ordered_extent *ordered;
+
+ spin_lock(&root->ordered_extent_lock);
+ /*
+ * This will just short circuit the ordered completion stuff which will
+ * make sure the ordered extent gets properly cleaned up.
+ */
+ list_for_each_entry(ordered, &root->ordered_extents,
+ root_extent_list)
+ set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
+ spin_unlock(&root->ordered_extent_lock);
+}
+
+static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *root;
+ struct list_head splice;
+
+ INIT_LIST_HEAD(&splice);
+
+ spin_lock(&fs_info->ordered_root_lock);
+ list_splice_init(&fs_info->ordered_roots, &splice);
+ while (!list_empty(&splice)) {
+ root = list_first_entry(&splice, struct btrfs_root,
+ ordered_root);
+ list_move_tail(&root->ordered_root,
+ &fs_info->ordered_roots);
+
+ spin_unlock(&fs_info->ordered_root_lock);
+ btrfs_destroy_ordered_extents(root);
+
+ cond_resched();
+ spin_lock(&fs_info->ordered_root_lock);
+ }
+ spin_unlock(&fs_info->ordered_root_lock);
+}
+
+static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
+ struct btrfs_root *root)
+{
+ struct rb_node *node;
+ struct btrfs_delayed_ref_root *delayed_refs;
+ struct btrfs_delayed_ref_node *ref;
+ int ret = 0;
+
+ delayed_refs = &trans->delayed_refs;
+
+ spin_lock(&delayed_refs->lock);
+ if (atomic_read(&delayed_refs->num_entries) == 0) {
+ spin_unlock(&delayed_refs->lock);
+ btrfs_info(root->fs_info, "delayed_refs has NO entry");
+ return ret;
+ }
+
+ while ((node = rb_first(&delayed_refs->href_root)) != NULL) {
+ struct btrfs_delayed_ref_head *head;
+ bool pin_bytes = false;
+
+ head = rb_entry(node, struct btrfs_delayed_ref_head,
+ href_node);
+ if (!mutex_trylock(&head->mutex)) {
+ atomic_inc(&head->node.refs);
+ spin_unlock(&delayed_refs->lock);
+
+ mutex_lock(&head->mutex);
+ mutex_unlock(&head->mutex);
+ btrfs_put_delayed_ref(&head->node);
+ spin_lock(&delayed_refs->lock);
+ continue;
+ }
+ spin_lock(&head->lock);
+ while ((node = rb_first(&head->ref_root)) != NULL) {
+ ref = rb_entry(node, struct btrfs_delayed_ref_node,
+ rb_node);
+ ref->in_tree = 0;
+ rb_erase(&ref->rb_node, &head->ref_root);
+ atomic_dec(&delayed_refs->num_entries);
+ btrfs_put_delayed_ref(ref);
+ }
+ if (head->must_insert_reserved)
+ pin_bytes = true;
+ btrfs_free_delayed_extent_op(head->extent_op);
+ delayed_refs->num_heads--;
+ if (head->processing == 0)
+ delayed_refs->num_heads_ready--;
+ atomic_dec(&delayed_refs->num_entries);
+ head->node.in_tree = 0;
+ rb_erase(&head->href_node, &delayed_refs->href_root);
+ spin_unlock(&head->lock);
+ spin_unlock(&delayed_refs->lock);
+ mutex_unlock(&head->mutex);
+
+ if (pin_bytes)
+ btrfs_pin_extent(root, head->node.bytenr,
+ head->node.num_bytes, 1);
+ btrfs_put_delayed_ref(&head->node);
+ cond_resched();
+ spin_lock(&delayed_refs->lock);
+ }
+
+ spin_unlock(&delayed_refs->lock);
+
+ return ret;
+}
+
+static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
+{
+ struct btrfs_inode *btrfs_inode;
+ struct list_head splice;
+
+ INIT_LIST_HEAD(&splice);
+
+ spin_lock(&root->delalloc_lock);
+ list_splice_init(&root->delalloc_inodes, &splice);
+
+ while (!list_empty(&splice)) {
+ btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
+ delalloc_inodes);
+
+ list_del_init(&btrfs_inode->delalloc_inodes);
+ clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
+ &btrfs_inode->runtime_flags);
+ spin_unlock(&root->delalloc_lock);
+
+ btrfs_invalidate_inodes(btrfs_inode->root);
+
+ spin_lock(&root->delalloc_lock);
+ }
+
+ spin_unlock(&root->delalloc_lock);
+}
+
+static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *root;
+ struct list_head splice;
+
+ INIT_LIST_HEAD(&splice);
+
+ spin_lock(&fs_info->delalloc_root_lock);
+ list_splice_init(&fs_info->delalloc_roots, &splice);
+ while (!list_empty(&splice)) {
+ root = list_first_entry(&splice, struct btrfs_root,
+ delalloc_root);
+ list_del_init(&root->delalloc_root);
+ root = btrfs_grab_fs_root(root);
+ BUG_ON(!root);
+ spin_unlock(&fs_info->delalloc_root_lock);
+
+ btrfs_destroy_delalloc_inodes(root);
+ btrfs_put_fs_root(root);
+
+ spin_lock(&fs_info->delalloc_root_lock);
+ }
+ spin_unlock(&fs_info->delalloc_root_lock);
+}
+
+static int btrfs_destroy_marked_extents(struct btrfs_root *root,
+ struct extent_io_tree *dirty_pages,
+ int mark)
+{
+ int ret;
+ struct extent_buffer *eb;
+ u64 start = 0;
+ u64 end;
+
+ while (1) {
+ ret = find_first_extent_bit(dirty_pages, start, &start, &end,
+ mark, NULL);
+ if (ret)
+ break;
+
+ clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
+ while (start <= end) {
+ eb = btrfs_find_tree_block(root->fs_info, start);
+ start += root->nodesize;
+ if (!eb)
+ continue;
+ wait_on_extent_buffer_writeback(eb);
+
+ if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
+ &eb->bflags))
+ clear_extent_buffer_dirty(eb);
+ free_extent_buffer_stale(eb);
+ }
+ }
+
+ return ret;
+}
+
+static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
+ struct extent_io_tree *pinned_extents)
+{
+ struct extent_io_tree *unpin;
+ u64 start;
+ u64 end;
+ int ret;
+ bool loop = true;
+
+ unpin = pinned_extents;
+again:
+ while (1) {
+ ret = find_first_extent_bit(unpin, 0, &start, &end,
+ EXTENT_DIRTY, NULL);
+ if (ret)
+ break;
+
+ clear_extent_dirty(unpin, start, end, GFP_NOFS);
+ btrfs_error_unpin_extent_range(root, start, end);
+ cond_resched();
+ }
+
+ if (loop) {
+ if (unpin == &root->fs_info->freed_extents[0])
+ unpin = &root->fs_info->freed_extents[1];
+ else
+ unpin = &root->fs_info->freed_extents[0];
+ loop = false;
+ goto again;
+ }
+
+ return 0;
+}
+
+static void btrfs_free_pending_ordered(struct btrfs_transaction *cur_trans,
+ struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_ordered_extent *ordered;
+
+ spin_lock(&fs_info->trans_lock);
+ while (!list_empty(&cur_trans->pending_ordered)) {
+ ordered = list_first_entry(&cur_trans->pending_ordered,
+ struct btrfs_ordered_extent,
+ trans_list);
+ list_del_init(&ordered->trans_list);
+ spin_unlock(&fs_info->trans_lock);
+
+ btrfs_put_ordered_extent(ordered);
+ spin_lock(&fs_info->trans_lock);
+ }
+ spin_unlock(&fs_info->trans_lock);
+}
+
+void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
+ struct btrfs_root *root)
+{
+ btrfs_destroy_delayed_refs(cur_trans, root);
+
+ cur_trans->state = TRANS_STATE_COMMIT_START;
+ wake_up(&root->fs_info->transaction_blocked_wait);
+
+ cur_trans->state = TRANS_STATE_UNBLOCKED;
+ wake_up(&root->fs_info->transaction_wait);
+
+ btrfs_free_pending_ordered(cur_trans, root->fs_info);
+ btrfs_destroy_delayed_inodes(root);
+ btrfs_assert_delayed_root_empty(root);
+
+ btrfs_destroy_marked_extents(root, &cur_trans->dirty_pages,
+ EXTENT_DIRTY);
+ btrfs_destroy_pinned_extent(root,
+ root->fs_info->pinned_extents);
+
+ cur_trans->state =TRANS_STATE_COMPLETED;
+ wake_up(&cur_trans->commit_wait);
+
+ /*
+ memset(cur_trans, 0, sizeof(*cur_trans));
+ kmem_cache_free(btrfs_transaction_cachep, cur_trans);
+ */
+}
+
+static int btrfs_cleanup_transaction(struct btrfs_root *root)
+{
+ struct btrfs_transaction *t;
+
+ mutex_lock(&root->fs_info->transaction_kthread_mutex);
+
+ spin_lock(&root->fs_info->trans_lock);
+ while (!list_empty(&root->fs_info->trans_list)) {
+ t = list_first_entry(&root->fs_info->trans_list,
+ struct btrfs_transaction, list);
+ if (t->state >= TRANS_STATE_COMMIT_START) {
+ atomic_inc(&t->use_count);
+ spin_unlock(&root->fs_info->trans_lock);
+ btrfs_wait_for_commit(root, t->transid);
+ btrfs_put_transaction(t);
+ spin_lock(&root->fs_info->trans_lock);
+ continue;
+ }
+ if (t == root->fs_info->running_transaction) {
+ t->state = TRANS_STATE_COMMIT_DOING;
+ spin_unlock(&root->fs_info->trans_lock);
+ /*
+ * We wait for 0 num_writers since we don't hold a trans
+ * handle open currently for this transaction.
+ */
+ wait_event(t->writer_wait,
+ atomic_read(&t->num_writers) == 0);
+ } else {
+ spin_unlock(&root->fs_info->trans_lock);
+ }
+ btrfs_cleanup_one_transaction(t, root);
+
+ spin_lock(&root->fs_info->trans_lock);
+ if (t == root->fs_info->running_transaction)
+ root->fs_info->running_transaction = NULL;
+ list_del_init(&t->list);
+ spin_unlock(&root->fs_info->trans_lock);
+
+ btrfs_put_transaction(t);
+ trace_btrfs_transaction_commit(root);
+ spin_lock(&root->fs_info->trans_lock);
+ }
+ spin_unlock(&root->fs_info->trans_lock);
+ btrfs_destroy_all_ordered_extents(root->fs_info);
+ btrfs_destroy_delayed_inodes(root);
+ btrfs_assert_delayed_root_empty(root);
+ btrfs_destroy_pinned_extent(root, root->fs_info->pinned_extents);
+ btrfs_destroy_all_delalloc_inodes(root->fs_info);
+ mutex_unlock(&root->fs_info->transaction_kthread_mutex);
+
+ return 0;
+}
+
+static const struct extent_io_ops btree_extent_io_ops = {
+ .readpage_end_io_hook = btree_readpage_end_io_hook,
+ .readpage_io_failed_hook = btree_io_failed_hook,
+ .submit_bio_hook = btree_submit_bio_hook,
+ /* note we're sharing with inode.c for the merge bio hook */
+ .merge_bio_hook = btrfs_merge_bio_hook,
+};
Code Review / kvmfornfv.git / blobdiff