--- /dev/null
+/*
+ * bmap.c - NILFS block mapping.
+ *
+ * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Written by Koji Sato <koji@osrg.net>.
+ */
+
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include "nilfs.h"
+#include "bmap.h"
+#include "btree.h"
+#include "direct.h"
+#include "btnode.h"
+#include "mdt.h"
+#include "dat.h"
+#include "alloc.h"
+
+struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *bmap)
+{
+ struct the_nilfs *nilfs = bmap->b_inode->i_sb->s_fs_info;
+
+ return nilfs->ns_dat;
+}
+
+static int nilfs_bmap_convert_error(struct nilfs_bmap *bmap,
+ const char *fname, int err)
+{
+ struct inode *inode = bmap->b_inode;
+
+ if (err == -EINVAL) {
+ nilfs_error(inode->i_sb, fname,
+ "broken bmap (inode number=%lu)\n", inode->i_ino);
+ err = -EIO;
+ }
+ return err;
+}
+
+/**
+ * nilfs_bmap_lookup_at_level - find a data block or node block
+ * @bmap: bmap
+ * @key: key
+ * @level: level
+ * @ptrp: place to store the value associated to @key
+ *
+ * Description: nilfs_bmap_lookup_at_level() finds a record whose key
+ * matches @key in the block at @level of the bmap.
+ *
+ * Return Value: On success, 0 is returned and the record associated with @key
+ * is stored in the place pointed by @ptrp. On error, one of the following
+ * negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ *
+ * %-ENOENT - A record associated with @key does not exist.
+ */
+int nilfs_bmap_lookup_at_level(struct nilfs_bmap *bmap, __u64 key, int level,
+ __u64 *ptrp)
+{
+ sector_t blocknr;
+ int ret;
+
+ down_read(&bmap->b_sem);
+ ret = bmap->b_ops->bop_lookup(bmap, key, level, ptrp);
+ if (ret < 0) {
+ ret = nilfs_bmap_convert_error(bmap, __func__, ret);
+ goto out;
+ }
+ if (NILFS_BMAP_USE_VBN(bmap)) {
+ ret = nilfs_dat_translate(nilfs_bmap_get_dat(bmap), *ptrp,
+ &blocknr);
+ if (!ret)
+ *ptrp = blocknr;
+ }
+
+ out:
+ up_read(&bmap->b_sem);
+ return ret;
+}
+
+int nilfs_bmap_lookup_contig(struct nilfs_bmap *bmap, __u64 key, __u64 *ptrp,
+ unsigned maxblocks)
+{
+ int ret;
+
+ down_read(&bmap->b_sem);
+ ret = bmap->b_ops->bop_lookup_contig(bmap, key, ptrp, maxblocks);
+ up_read(&bmap->b_sem);
+
+ return nilfs_bmap_convert_error(bmap, __func__, ret);
+}
+
+static int nilfs_bmap_do_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
+{
+ __u64 keys[NILFS_BMAP_SMALL_HIGH + 1];
+ __u64 ptrs[NILFS_BMAP_SMALL_HIGH + 1];
+ int ret, n;
+
+ if (bmap->b_ops->bop_check_insert != NULL) {
+ ret = bmap->b_ops->bop_check_insert(bmap, key);
+ if (ret > 0) {
+ n = bmap->b_ops->bop_gather_data(
+ bmap, keys, ptrs, NILFS_BMAP_SMALL_HIGH + 1);
+ if (n < 0)
+ return n;
+ ret = nilfs_btree_convert_and_insert(
+ bmap, key, ptr, keys, ptrs, n);
+ if (ret == 0)
+ bmap->b_u.u_flags |= NILFS_BMAP_LARGE;
+
+ return ret;
+ } else if (ret < 0)
+ return ret;
+ }
+
+ return bmap->b_ops->bop_insert(bmap, key, ptr);
+}
+
+/**
+ * nilfs_bmap_insert - insert a new key-record pair into a bmap
+ * @bmap: bmap
+ * @key: key
+ * @rec: record
+ *
+ * Description: nilfs_bmap_insert() inserts the new key-record pair specified
+ * by @key and @rec into @bmap.
+ *
+ * Return Value: On success, 0 is returned. On error, one of the following
+ * negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ *
+ * %-EEXIST - A record associated with @key already exist.
+ */
+int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec)
+{
+ int ret;
+
+ down_write(&bmap->b_sem);
+ ret = nilfs_bmap_do_insert(bmap, key, rec);
+ up_write(&bmap->b_sem);
+
+ return nilfs_bmap_convert_error(bmap, __func__, ret);
+}
+
+static int nilfs_bmap_do_delete(struct nilfs_bmap *bmap, __u64 key)
+{
+ __u64 keys[NILFS_BMAP_LARGE_LOW + 1];
+ __u64 ptrs[NILFS_BMAP_LARGE_LOW + 1];
+ int ret, n;
+
+ if (bmap->b_ops->bop_check_delete != NULL) {
+ ret = bmap->b_ops->bop_check_delete(bmap, key);
+ if (ret > 0) {
+ n = bmap->b_ops->bop_gather_data(
+ bmap, keys, ptrs, NILFS_BMAP_LARGE_LOW + 1);
+ if (n < 0)
+ return n;
+ ret = nilfs_direct_delete_and_convert(
+ bmap, key, keys, ptrs, n);
+ if (ret == 0)
+ bmap->b_u.u_flags &= ~NILFS_BMAP_LARGE;
+
+ return ret;
+ } else if (ret < 0)
+ return ret;
+ }
+
+ return bmap->b_ops->bop_delete(bmap, key);
+}
+
+/**
+ * nilfs_bmap_seek_key - seek a valid entry and return its key
+ * @bmap: bmap struct
+ * @start: start key number
+ * @keyp: place to store valid key
+ *
+ * Description: nilfs_bmap_seek_key() seeks a valid key on @bmap
+ * starting from @start, and stores it to @keyp if found.
+ *
+ * Return Value: On success, 0 is returned. On error, one of the following
+ * negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ *
+ * %-ENOENT - No valid entry was found
+ */
+int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp)
+{
+ int ret;
+
+ down_read(&bmap->b_sem);
+ ret = bmap->b_ops->bop_seek_key(bmap, start, keyp);
+ up_read(&bmap->b_sem);
+
+ if (ret < 0)
+ ret = nilfs_bmap_convert_error(bmap, __func__, ret);
+ return ret;
+}
+
+int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp)
+{
+ int ret;
+
+ down_read(&bmap->b_sem);
+ ret = bmap->b_ops->bop_last_key(bmap, keyp);
+ up_read(&bmap->b_sem);
+
+ if (ret < 0)
+ ret = nilfs_bmap_convert_error(bmap, __func__, ret);
+ return ret;
+}
+
+/**
+ * nilfs_bmap_delete - delete a key-record pair from a bmap
+ * @bmap: bmap
+ * @key: key
+ *
+ * Description: nilfs_bmap_delete() deletes the key-record pair specified by
+ * @key from @bmap.
+ *
+ * Return Value: On success, 0 is returned. On error, one of the following
+ * negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ *
+ * %-ENOENT - A record associated with @key does not exist.
+ */
+int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key)
+{
+ int ret;
+
+ down_write(&bmap->b_sem);
+ ret = nilfs_bmap_do_delete(bmap, key);
+ up_write(&bmap->b_sem);
+
+ return nilfs_bmap_convert_error(bmap, __func__, ret);
+}
+
+static int nilfs_bmap_do_truncate(struct nilfs_bmap *bmap, __u64 key)
+{
+ __u64 lastkey;
+ int ret;
+
+ ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
+ if (ret < 0) {
+ if (ret == -ENOENT)
+ ret = 0;
+ return ret;
+ }
+
+ while (key <= lastkey) {
+ ret = nilfs_bmap_do_delete(bmap, lastkey);
+ if (ret < 0)
+ return ret;
+ ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
+ if (ret < 0) {
+ if (ret == -ENOENT)
+ ret = 0;
+ return ret;
+ }
+ }
+ return 0;
+}
+
+/**
+ * nilfs_bmap_truncate - truncate a bmap to a specified key
+ * @bmap: bmap
+ * @key: key
+ *
+ * Description: nilfs_bmap_truncate() removes key-record pairs whose keys are
+ * greater than or equal to @key from @bmap.
+ *
+ * Return Value: On success, 0 is returned. On error, one of the following
+ * negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ */
+int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key)
+{
+ int ret;
+
+ down_write(&bmap->b_sem);
+ ret = nilfs_bmap_do_truncate(bmap, key);
+ up_write(&bmap->b_sem);
+
+ return nilfs_bmap_convert_error(bmap, __func__, ret);
+}
+
+/**
+ * nilfs_bmap_clear - free resources a bmap holds
+ * @bmap: bmap
+ *
+ * Description: nilfs_bmap_clear() frees resources associated with @bmap.
+ */
+void nilfs_bmap_clear(struct nilfs_bmap *bmap)
+{
+ down_write(&bmap->b_sem);
+ if (bmap->b_ops->bop_clear != NULL)
+ bmap->b_ops->bop_clear(bmap);
+ up_write(&bmap->b_sem);
+}
+
+/**
+ * nilfs_bmap_propagate - propagate dirty state
+ * @bmap: bmap
+ * @bh: buffer head
+ *
+ * Description: nilfs_bmap_propagate() marks the buffers that directly or
+ * indirectly refer to the block specified by @bh dirty.
+ *
+ * Return Value: On success, 0 is returned. On error, one of the following
+ * negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ */
+int nilfs_bmap_propagate(struct nilfs_bmap *bmap, struct buffer_head *bh)
+{
+ int ret;
+
+ down_write(&bmap->b_sem);
+ ret = bmap->b_ops->bop_propagate(bmap, bh);
+ up_write(&bmap->b_sem);
+
+ return nilfs_bmap_convert_error(bmap, __func__, ret);
+}
+
+/**
+ * nilfs_bmap_lookup_dirty_buffers -
+ * @bmap: bmap
+ * @listp: pointer to buffer head list
+ */
+void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *bmap,
+ struct list_head *listp)
+{
+ if (bmap->b_ops->bop_lookup_dirty_buffers != NULL)
+ bmap->b_ops->bop_lookup_dirty_buffers(bmap, listp);
+}
+
+/**
+ * nilfs_bmap_assign - assign a new block number to a block
+ * @bmap: bmap
+ * @bhp: pointer to buffer head
+ * @blocknr: block number
+ * @binfo: block information
+ *
+ * Description: nilfs_bmap_assign() assigns the block number @blocknr to the
+ * buffer specified by @bh.
+ *
+ * Return Value: On success, 0 is returned and the buffer head of a newly
+ * create buffer and the block information associated with the buffer are
+ * stored in the place pointed by @bh and @binfo, respectively. On error, one
+ * of the following negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ */
+int nilfs_bmap_assign(struct nilfs_bmap *bmap,
+ struct buffer_head **bh,
+ unsigned long blocknr,
+ union nilfs_binfo *binfo)
+{
+ int ret;
+
+ down_write(&bmap->b_sem);
+ ret = bmap->b_ops->bop_assign(bmap, bh, blocknr, binfo);
+ up_write(&bmap->b_sem);
+
+ return nilfs_bmap_convert_error(bmap, __func__, ret);
+}
+
+/**
+ * nilfs_bmap_mark - mark block dirty
+ * @bmap: bmap
+ * @key: key
+ * @level: level
+ *
+ * Description: nilfs_bmap_mark() marks the block specified by @key and @level
+ * as dirty.
+ *
+ * Return Value: On success, 0 is returned. On error, one of the following
+ * negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ */
+int nilfs_bmap_mark(struct nilfs_bmap *bmap, __u64 key, int level)
+{
+ int ret;
+
+ if (bmap->b_ops->bop_mark == NULL)
+ return 0;
+
+ down_write(&bmap->b_sem);
+ ret = bmap->b_ops->bop_mark(bmap, key, level);
+ up_write(&bmap->b_sem);
+
+ return nilfs_bmap_convert_error(bmap, __func__, ret);
+}
+
+/**
+ * nilfs_bmap_test_and_clear_dirty - test and clear a bmap dirty state
+ * @bmap: bmap
+ *
+ * Description: nilfs_test_and_clear() is the atomic operation to test and
+ * clear the dirty state of @bmap.
+ *
+ * Return Value: 1 is returned if @bmap is dirty, or 0 if clear.
+ */
+int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *bmap)
+{
+ int ret;
+
+ down_write(&bmap->b_sem);
+ ret = nilfs_bmap_dirty(bmap);
+ nilfs_bmap_clear_dirty(bmap);
+ up_write(&bmap->b_sem);
+ return ret;
+}
+
+
+/*
+ * Internal use only
+ */
+__u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *bmap,
+ const struct buffer_head *bh)
+{
+ struct buffer_head *pbh;
+ __u64 key;
+
+ key = page_index(bh->b_page) << (PAGE_CACHE_SHIFT -
+ bmap->b_inode->i_blkbits);
+ for (pbh = page_buffers(bh->b_page); pbh != bh; pbh = pbh->b_this_page)
+ key++;
+
+ return key;
+}
+
+__u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *bmap, __u64 key)
+{
+ __s64 diff;
+
+ diff = key - bmap->b_last_allocated_key;
+ if ((nilfs_bmap_keydiff_abs(diff) < NILFS_INODE_BMAP_SIZE) &&
+ (bmap->b_last_allocated_ptr != NILFS_BMAP_INVALID_PTR) &&
+ (bmap->b_last_allocated_ptr + diff > 0))
+ return bmap->b_last_allocated_ptr + diff;
+ else
+ return NILFS_BMAP_INVALID_PTR;
+}
+
+#define NILFS_BMAP_GROUP_DIV 8
+__u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *bmap)
+{
+ struct inode *dat = nilfs_bmap_get_dat(bmap);
+ unsigned long entries_per_group = nilfs_palloc_entries_per_group(dat);
+ unsigned long group = bmap->b_inode->i_ino / entries_per_group;
+
+ return group * entries_per_group +
+ (bmap->b_inode->i_ino % NILFS_BMAP_GROUP_DIV) *
+ (entries_per_group / NILFS_BMAP_GROUP_DIV);
+}
+
+static struct lock_class_key nilfs_bmap_dat_lock_key;
+static struct lock_class_key nilfs_bmap_mdt_lock_key;
+
+/**
+ * nilfs_bmap_read - read a bmap from an inode
+ * @bmap: bmap
+ * @raw_inode: on-disk inode
+ *
+ * Description: nilfs_bmap_read() initializes the bmap @bmap.
+ *
+ * Return Value: On success, 0 is returned. On error, the following negative
+ * error code is returned.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ */
+int nilfs_bmap_read(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
+{
+ if (raw_inode == NULL)
+ memset(bmap->b_u.u_data, 0, NILFS_BMAP_SIZE);
+ else
+ memcpy(bmap->b_u.u_data, raw_inode->i_bmap, NILFS_BMAP_SIZE);
+
+ init_rwsem(&bmap->b_sem);
+ bmap->b_state = 0;
+ bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
+ switch (bmap->b_inode->i_ino) {
+ case NILFS_DAT_INO:
+ bmap->b_ptr_type = NILFS_BMAP_PTR_P;
+ bmap->b_last_allocated_key = 0;
+ bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
+ lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
+ break;
+ case NILFS_CPFILE_INO:
+ case NILFS_SUFILE_INO:
+ bmap->b_ptr_type = NILFS_BMAP_PTR_VS;
+ bmap->b_last_allocated_key = 0;
+ bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
+ lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
+ break;
+ case NILFS_IFILE_INO:
+ lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
+ /* Fall through */
+ default:
+ bmap->b_ptr_type = NILFS_BMAP_PTR_VM;
+ bmap->b_last_allocated_key = 0;
+ bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
+ break;
+ }
+
+ return (bmap->b_u.u_flags & NILFS_BMAP_LARGE) ?
+ nilfs_btree_init(bmap) : nilfs_direct_init(bmap);
+}
+
+/**
+ * nilfs_bmap_write - write back a bmap to an inode
+ * @bmap: bmap
+ * @raw_inode: on-disk inode
+ *
+ * Description: nilfs_bmap_write() stores @bmap in @raw_inode.
+ */
+void nilfs_bmap_write(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
+{
+ down_write(&bmap->b_sem);
+ memcpy(raw_inode->i_bmap, bmap->b_u.u_data,
+ NILFS_INODE_BMAP_SIZE * sizeof(__le64));
+ if (bmap->b_inode->i_ino == NILFS_DAT_INO)
+ bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
+
+ up_write(&bmap->b_sem);
+}
+
+void nilfs_bmap_init_gc(struct nilfs_bmap *bmap)
+{
+ memset(&bmap->b_u, 0, NILFS_BMAP_SIZE);
+ init_rwsem(&bmap->b_sem);
+ bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
+ bmap->b_ptr_type = NILFS_BMAP_PTR_U;
+ bmap->b_last_allocated_key = 0;
+ bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
+ bmap->b_state = 0;
+ nilfs_btree_init_gc(bmap);
+}
+
+void nilfs_bmap_save(const struct nilfs_bmap *bmap,
+ struct nilfs_bmap_store *store)
+{
+ memcpy(store->data, bmap->b_u.u_data, sizeof(store->data));
+ store->last_allocated_key = bmap->b_last_allocated_key;
+ store->last_allocated_ptr = bmap->b_last_allocated_ptr;
+ store->state = bmap->b_state;
+}
+
+void nilfs_bmap_restore(struct nilfs_bmap *bmap,
+ const struct nilfs_bmap_store *store)
+{
+ memcpy(bmap->b_u.u_data, store->data, sizeof(store->data));
+ bmap->b_last_allocated_key = store->last_allocated_key;
+ bmap->b_last_allocated_ptr = store->last_allocated_ptr;
+ bmap->b_state = store->state;
+}
Code Review / kvmfornfv.git / blobdiff