--- /dev/null
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * Copyright (C) 2002, 2004 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 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., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <asm/byteorder.h>
+#include <linux/swap.h>
+#include <linux/pipe_fs_i.h>
+#include <linux/mpage.h>
+#include <linux/quotaops.h>
+#include <linux/blkdev.h>
+#include <linux/uio.h>
+
+#include <cluster/masklog.h>
+
+#include "ocfs2.h"
+
+#include "alloc.h"
+#include "aops.h"
+#include "dlmglue.h"
+#include "extent_map.h"
+#include "file.h"
+#include "inode.h"
+#include "journal.h"
+#include "suballoc.h"
+#include "super.h"
+#include "symlink.h"
+#include "refcounttree.h"
+#include "ocfs2_trace.h"
+
+#include "buffer_head_io.h"
+#include "dir.h"
+#include "namei.h"
+#include "sysfile.h"
+
+static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ int err = -EIO;
+ int status;
+ struct ocfs2_dinode *fe = NULL;
+ struct buffer_head *bh = NULL;
+ struct buffer_head *buffer_cache_bh = NULL;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ void *kaddr;
+
+ trace_ocfs2_symlink_get_block(
+ (unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)iblock, bh_result, create);
+
+ BUG_ON(ocfs2_inode_is_fast_symlink(inode));
+
+ if ((iblock << inode->i_sb->s_blocksize_bits) > PATH_MAX + 1) {
+ mlog(ML_ERROR, "block offset > PATH_MAX: %llu",
+ (unsigned long long)iblock);
+ goto bail;
+ }
+
+ status = ocfs2_read_inode_block(inode, &bh);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+ fe = (struct ocfs2_dinode *) bh->b_data;
+
+ if ((u64)iblock >= ocfs2_clusters_to_blocks(inode->i_sb,
+ le32_to_cpu(fe->i_clusters))) {
+ err = -ENOMEM;
+ mlog(ML_ERROR, "block offset is outside the allocated size: "
+ "%llu\n", (unsigned long long)iblock);
+ goto bail;
+ }
+
+ /* We don't use the page cache to create symlink data, so if
+ * need be, copy it over from the buffer cache. */
+ if (!buffer_uptodate(bh_result) && ocfs2_inode_is_new(inode)) {
+ u64 blkno = le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) +
+ iblock;
+ buffer_cache_bh = sb_getblk(osb->sb, blkno);
+ if (!buffer_cache_bh) {
+ err = -ENOMEM;
+ mlog(ML_ERROR, "couldn't getblock for symlink!\n");
+ goto bail;
+ }
+
+ /* we haven't locked out transactions, so a commit
+ * could've happened. Since we've got a reference on
+ * the bh, even if it commits while we're doing the
+ * copy, the data is still good. */
+ if (buffer_jbd(buffer_cache_bh)
+ && ocfs2_inode_is_new(inode)) {
+ kaddr = kmap_atomic(bh_result->b_page);
+ if (!kaddr) {
+ mlog(ML_ERROR, "couldn't kmap!\n");
+ goto bail;
+ }
+ memcpy(kaddr + (bh_result->b_size * iblock),
+ buffer_cache_bh->b_data,
+ bh_result->b_size);
+ kunmap_atomic(kaddr);
+ set_buffer_uptodate(bh_result);
+ }
+ brelse(buffer_cache_bh);
+ }
+
+ map_bh(bh_result, inode->i_sb,
+ le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) + iblock);
+
+ err = 0;
+
+bail:
+ brelse(bh);
+
+ return err;
+}
+
+int ocfs2_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ int err = 0;
+ unsigned int ext_flags;
+ u64 max_blocks = bh_result->b_size >> inode->i_blkbits;
+ u64 p_blkno, count, past_eof;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+ trace_ocfs2_get_block((unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)iblock, bh_result, create);
+
+ if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE)
+ mlog(ML_NOTICE, "get_block on system inode 0x%p (%lu)\n",
+ inode, inode->i_ino);
+
+ if (S_ISLNK(inode->i_mode)) {
+ /* this always does I/O for some reason. */
+ err = ocfs2_symlink_get_block(inode, iblock, bh_result, create);
+ goto bail;
+ }
+
+ err = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno, &count,
+ &ext_flags);
+ if (err) {
+ mlog(ML_ERROR, "Error %d from get_blocks(0x%p, %llu, 1, "
+ "%llu, NULL)\n", err, inode, (unsigned long long)iblock,
+ (unsigned long long)p_blkno);
+ goto bail;
+ }
+
+ if (max_blocks < count)
+ count = max_blocks;
+
+ /*
+ * ocfs2 never allocates in this function - the only time we
+ * need to use BH_New is when we're extending i_size on a file
+ * system which doesn't support holes, in which case BH_New
+ * allows __block_write_begin() to zero.
+ *
+ * If we see this on a sparse file system, then a truncate has
+ * raced us and removed the cluster. In this case, we clear
+ * the buffers dirty and uptodate bits and let the buffer code
+ * ignore it as a hole.
+ */
+ if (create && p_blkno == 0 && ocfs2_sparse_alloc(osb)) {
+ clear_buffer_dirty(bh_result);
+ clear_buffer_uptodate(bh_result);
+ goto bail;
+ }
+
+ /* Treat the unwritten extent as a hole for zeroing purposes. */
+ if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
+ map_bh(bh_result, inode->i_sb, p_blkno);
+
+ bh_result->b_size = count << inode->i_blkbits;
+
+ if (!ocfs2_sparse_alloc(osb)) {
+ if (p_blkno == 0) {
+ err = -EIO;
+ mlog(ML_ERROR,
+ "iblock = %llu p_blkno = %llu blkno=(%llu)\n",
+ (unsigned long long)iblock,
+ (unsigned long long)p_blkno,
+ (unsigned long long)OCFS2_I(inode)->ip_blkno);
+ mlog(ML_ERROR, "Size %llu, clusters %u\n", (unsigned long long)i_size_read(inode), OCFS2_I(inode)->ip_clusters);
+ dump_stack();
+ goto bail;
+ }
+ }
+
+ past_eof = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
+
+ trace_ocfs2_get_block_end((unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)past_eof);
+ if (create && (iblock >= past_eof))
+ set_buffer_new(bh_result);
+
+bail:
+ if (err < 0)
+ err = -EIO;
+
+ return err;
+}
+
+int ocfs2_read_inline_data(struct inode *inode, struct page *page,
+ struct buffer_head *di_bh)
+{
+ void *kaddr;
+ loff_t size;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+
+ if (!(le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL)) {
+ ocfs2_error(inode->i_sb, "Inode %llu lost inline data flag",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno);
+ return -EROFS;
+ }
+
+ size = i_size_read(inode);
+
+ if (size > PAGE_CACHE_SIZE ||
+ size > ocfs2_max_inline_data_with_xattr(inode->i_sb, di)) {
+ ocfs2_error(inode->i_sb,
+ "Inode %llu has with inline data has bad size: %Lu",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)size);
+ return -EROFS;
+ }
+
+ kaddr = kmap_atomic(page);
+ if (size)
+ memcpy(kaddr, di->id2.i_data.id_data, size);
+ /* Clear the remaining part of the page */
+ memset(kaddr + size, 0, PAGE_CACHE_SIZE - size);
+ flush_dcache_page(page);
+ kunmap_atomic(kaddr);
+
+ SetPageUptodate(page);
+
+ return 0;
+}
+
+static int ocfs2_readpage_inline(struct inode *inode, struct page *page)
+{
+ int ret;
+ struct buffer_head *di_bh = NULL;
+
+ BUG_ON(!PageLocked(page));
+ BUG_ON(!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL));
+
+ ret = ocfs2_read_inode_block(inode, &di_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_read_inline_data(inode, page, di_bh);
+out:
+ unlock_page(page);
+
+ brelse(di_bh);
+ return ret;
+}
+
+static int ocfs2_readpage(struct file *file, struct page *page)
+{
+ struct inode *inode = page->mapping->host;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ loff_t start = (loff_t)page->index << PAGE_CACHE_SHIFT;
+ int ret, unlock = 1;
+
+ trace_ocfs2_readpage((unsigned long long)oi->ip_blkno,
+ (page ? page->index : 0));
+
+ ret = ocfs2_inode_lock_with_page(inode, NULL, 0, page);
+ if (ret != 0) {
+ if (ret == AOP_TRUNCATED_PAGE)
+ unlock = 0;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
+ /*
+ * Unlock the page and cycle ip_alloc_sem so that we don't
+ * busyloop waiting for ip_alloc_sem to unlock
+ */
+ ret = AOP_TRUNCATED_PAGE;
+ unlock_page(page);
+ unlock = 0;
+ down_read(&oi->ip_alloc_sem);
+ up_read(&oi->ip_alloc_sem);
+ goto out_inode_unlock;
+ }
+
+ /*
+ * i_size might have just been updated as we grabed the meta lock. We
+ * might now be discovering a truncate that hit on another node.
+ * block_read_full_page->get_block freaks out if it is asked to read
+ * beyond the end of a file, so we check here. Callers
+ * (generic_file_read, vm_ops->fault) are clever enough to check i_size
+ * and notice that the page they just read isn't needed.
+ *
+ * XXX sys_readahead() seems to get that wrong?
+ */
+ if (start >= i_size_read(inode)) {
+ zero_user(page, 0, PAGE_SIZE);
+ SetPageUptodate(page);
+ ret = 0;
+ goto out_alloc;
+ }
+
+ if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+ ret = ocfs2_readpage_inline(inode, page);
+ else
+ ret = block_read_full_page(page, ocfs2_get_block);
+ unlock = 0;
+
+out_alloc:
+ up_read(&OCFS2_I(inode)->ip_alloc_sem);
+out_inode_unlock:
+ ocfs2_inode_unlock(inode, 0);
+out:
+ if (unlock)
+ unlock_page(page);
+ return ret;
+}
+
+/*
+ * This is used only for read-ahead. Failures or difficult to handle
+ * situations are safe to ignore.
+ *
+ * Right now, we don't bother with BH_Boundary - in-inode extent lists
+ * are quite large (243 extents on 4k blocks), so most inodes don't
+ * grow out to a tree. If need be, detecting boundary extents could
+ * trivially be added in a future version of ocfs2_get_block().
+ */
+static int ocfs2_readpages(struct file *filp, struct address_space *mapping,
+ struct list_head *pages, unsigned nr_pages)
+{
+ int ret, err = -EIO;
+ struct inode *inode = mapping->host;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ loff_t start;
+ struct page *last;
+
+ /*
+ * Use the nonblocking flag for the dlm code to avoid page
+ * lock inversion, but don't bother with retrying.
+ */
+ ret = ocfs2_inode_lock_full(inode, NULL, 0, OCFS2_LOCK_NONBLOCK);
+ if (ret)
+ return err;
+
+ if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
+ ocfs2_inode_unlock(inode, 0);
+ return err;
+ }
+
+ /*
+ * Don't bother with inline-data. There isn't anything
+ * to read-ahead in that case anyway...
+ */
+ if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+ goto out_unlock;
+
+ /*
+ * Check whether a remote node truncated this file - we just
+ * drop out in that case as it's not worth handling here.
+ */
+ last = list_entry(pages->prev, struct page, lru);
+ start = (loff_t)last->index << PAGE_CACHE_SHIFT;
+ if (start >= i_size_read(inode))
+ goto out_unlock;
+
+ err = mpage_readpages(mapping, pages, nr_pages, ocfs2_get_block);
+
+out_unlock:
+ up_read(&oi->ip_alloc_sem);
+ ocfs2_inode_unlock(inode, 0);
+
+ return err;
+}
+
+/* Note: Because we don't support holes, our allocation has
+ * already happened (allocation writes zeros to the file data)
+ * so we don't have to worry about ordered writes in
+ * ocfs2_writepage.
+ *
+ * ->writepage is called during the process of invalidating the page cache
+ * during blocked lock processing. It can't block on any cluster locks
+ * to during block mapping. It's relying on the fact that the block
+ * mapping can't have disappeared under the dirty pages that it is
+ * being asked to write back.
+ */
+static int ocfs2_writepage(struct page *page, struct writeback_control *wbc)
+{
+ trace_ocfs2_writepage(
+ (unsigned long long)OCFS2_I(page->mapping->host)->ip_blkno,
+ page->index);
+
+ return block_write_full_page(page, ocfs2_get_block, wbc);
+}
+
+/* Taken from ext3. We don't necessarily need the full blown
+ * functionality yet, but IMHO it's better to cut and paste the whole
+ * thing so we can avoid introducing our own bugs (and easily pick up
+ * their fixes when they happen) --Mark */
+int walk_page_buffers( handle_t *handle,
+ struct buffer_head *head,
+ unsigned from,
+ unsigned to,
+ int *partial,
+ int (*fn)( handle_t *handle,
+ struct buffer_head *bh))
+{
+ struct buffer_head *bh;
+ unsigned block_start, block_end;
+ unsigned blocksize = head->b_size;
+ int err, ret = 0;
+ struct buffer_head *next;
+
+ for ( bh = head, block_start = 0;
+ ret == 0 && (bh != head || !block_start);
+ block_start = block_end, bh = next)
+ {
+ next = bh->b_this_page;
+ block_end = block_start + blocksize;
+ if (block_end <= from || block_start >= to) {
+ if (partial && !buffer_uptodate(bh))
+ *partial = 1;
+ continue;
+ }
+ err = (*fn)(handle, bh);
+ if (!ret)
+ ret = err;
+ }
+ return ret;
+}
+
+static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block)
+{
+ sector_t status;
+ u64 p_blkno = 0;
+ int err = 0;
+ struct inode *inode = mapping->host;
+
+ trace_ocfs2_bmap((unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)block);
+
+ /* We don't need to lock journal system files, since they aren't
+ * accessed concurrently from multiple nodes.
+ */
+ if (!INODE_JOURNAL(inode)) {
+ err = ocfs2_inode_lock(inode, NULL, 0);
+ if (err) {
+ if (err != -ENOENT)
+ mlog_errno(err);
+ goto bail;
+ }
+ down_read(&OCFS2_I(inode)->ip_alloc_sem);
+ }
+
+ if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL))
+ err = ocfs2_extent_map_get_blocks(inode, block, &p_blkno, NULL,
+ NULL);
+
+ if (!INODE_JOURNAL(inode)) {
+ up_read(&OCFS2_I(inode)->ip_alloc_sem);
+ ocfs2_inode_unlock(inode, 0);
+ }
+
+ if (err) {
+ mlog(ML_ERROR, "get_blocks() failed, block = %llu\n",
+ (unsigned long long)block);
+ mlog_errno(err);
+ goto bail;
+ }
+
+bail:
+ status = err ? 0 : p_blkno;
+
+ return status;
+}
+
+/*
+ * TODO: Make this into a generic get_blocks function.
+ *
+ * From do_direct_io in direct-io.c:
+ * "So what we do is to permit the ->get_blocks function to populate
+ * bh.b_size with the size of IO which is permitted at this offset and
+ * this i_blkbits."
+ *
+ * This function is called directly from get_more_blocks in direct-io.c.
+ *
+ * called like this: dio->get_blocks(dio->inode, fs_startblk,
+ * fs_count, map_bh, dio->rw == WRITE);
+ */
+static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ int ret;
+ u32 cpos = 0;
+ int alloc_locked = 0;
+ u64 p_blkno, inode_blocks, contig_blocks;
+ unsigned int ext_flags;
+ unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
+ unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
+ unsigned long len = bh_result->b_size;
+ unsigned int clusters_to_alloc = 0;
+
+ cpos = ocfs2_blocks_to_clusters(inode->i_sb, iblock);
+
+ /* This function won't even be called if the request isn't all
+ * nicely aligned and of the right size, so there's no need
+ * for us to check any of that. */
+
+ inode_blocks = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
+
+ /* This figures out the size of the next contiguous block, and
+ * our logical offset */
+ ret = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno,
+ &contig_blocks, &ext_flags);
+ if (ret) {
+ mlog(ML_ERROR, "get_blocks() failed iblock=%llu\n",
+ (unsigned long long)iblock);
+ ret = -EIO;
+ goto bail;
+ }
+
+ /* We should already CoW the refcounted extent in case of create. */
+ BUG_ON(create && (ext_flags & OCFS2_EXT_REFCOUNTED));
+
+ /* allocate blocks if no p_blkno is found, and create == 1 */
+ if (!p_blkno && create) {
+ ret = ocfs2_inode_lock(inode, NULL, 1);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ alloc_locked = 1;
+
+ /* fill hole, allocate blocks can't be larger than the size
+ * of the hole */
+ clusters_to_alloc = ocfs2_clusters_for_bytes(inode->i_sb, len);
+ if (clusters_to_alloc > contig_blocks)
+ clusters_to_alloc = contig_blocks;
+
+ /* allocate extent and insert them into the extent tree */
+ ret = ocfs2_extend_allocation(inode, cpos,
+ clusters_to_alloc, 0);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ ret = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno,
+ &contig_blocks, &ext_flags);
+ if (ret < 0) {
+ mlog(ML_ERROR, "get_blocks() failed iblock=%llu\n",
+ (unsigned long long)iblock);
+ ret = -EIO;
+ goto bail;
+ }
+ }
+
+ /*
+ * get_more_blocks() expects us to describe a hole by clearing
+ * the mapped bit on bh_result().
+ *
+ * Consider an unwritten extent as a hole.
+ */
+ if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
+ map_bh(bh_result, inode->i_sb, p_blkno);
+ else
+ clear_buffer_mapped(bh_result);
+
+ /* make sure we don't map more than max_blocks blocks here as
+ that's all the kernel will handle at this point. */
+ if (max_blocks < contig_blocks)
+ contig_blocks = max_blocks;
+ bh_result->b_size = contig_blocks << blocksize_bits;
+bail:
+ if (alloc_locked)
+ ocfs2_inode_unlock(inode, 1);
+ return ret;
+}
+
+/*
+ * ocfs2_dio_end_io is called by the dio core when a dio is finished. We're
+ * particularly interested in the aio/dio case. We use the rw_lock DLM lock
+ * to protect io on one node from truncation on another.
+ */
+static void ocfs2_dio_end_io(struct kiocb *iocb,
+ loff_t offset,
+ ssize_t bytes,
+ void *private)
+{
+ struct inode *inode = file_inode(iocb->ki_filp);
+ int level;
+
+ /* this io's submitter should not have unlocked this before we could */
+ BUG_ON(!ocfs2_iocb_is_rw_locked(iocb));
+
+ if (ocfs2_iocb_is_sem_locked(iocb))
+ ocfs2_iocb_clear_sem_locked(iocb);
+
+ if (ocfs2_iocb_is_unaligned_aio(iocb)) {
+ ocfs2_iocb_clear_unaligned_aio(iocb);
+
+ mutex_unlock(&OCFS2_I(inode)->ip_unaligned_aio);
+ }
+
+ ocfs2_iocb_clear_rw_locked(iocb);
+
+ level = ocfs2_iocb_rw_locked_level(iocb);
+ ocfs2_rw_unlock(inode, level);
+}
+
+static int ocfs2_releasepage(struct page *page, gfp_t wait)
+{
+ if (!page_has_buffers(page))
+ return 0;
+ return try_to_free_buffers(page);
+}
+
+static int ocfs2_is_overwrite(struct ocfs2_super *osb,
+ struct inode *inode, loff_t offset)
+{
+ int ret = 0;
+ u32 v_cpos = 0;
+ u32 p_cpos = 0;
+ unsigned int num_clusters = 0;
+ unsigned int ext_flags = 0;
+
+ v_cpos = ocfs2_bytes_to_clusters(osb->sb, offset);
+ ret = ocfs2_get_clusters(inode, v_cpos, &p_cpos,
+ &num_clusters, &ext_flags);
+ if (ret < 0) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ if (p_cpos && !(ext_flags & OCFS2_EXT_UNWRITTEN))
+ return 1;
+
+ return 0;
+}
+
+static int ocfs2_direct_IO_zero_extend(struct ocfs2_super *osb,
+ struct inode *inode, loff_t offset,
+ u64 zero_len, int cluster_align)
+{
+ u32 p_cpos = 0;
+ u32 v_cpos = ocfs2_bytes_to_clusters(osb->sb, i_size_read(inode));
+ unsigned int num_clusters = 0;
+ unsigned int ext_flags = 0;
+ int ret = 0;
+
+ if (offset <= i_size_read(inode) || cluster_align)
+ return 0;
+
+ ret = ocfs2_get_clusters(inode, v_cpos, &p_cpos, &num_clusters,
+ &ext_flags);
+ if (ret < 0) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ if (p_cpos && !(ext_flags & OCFS2_EXT_UNWRITTEN)) {
+ u64 s = i_size_read(inode);
+ sector_t sector = (p_cpos << (osb->s_clustersize_bits - 9)) +
+ (do_div(s, osb->s_clustersize) >> 9);
+
+ ret = blkdev_issue_zeroout(osb->sb->s_bdev, sector,
+ zero_len >> 9, GFP_NOFS, false);
+ if (ret < 0)
+ mlog_errno(ret);
+ }
+
+ return ret;
+}
+
+static int ocfs2_direct_IO_extend_no_holes(struct ocfs2_super *osb,
+ struct inode *inode, loff_t offset)
+{
+ u64 zero_start, zero_len, total_zero_len;
+ u32 p_cpos = 0, clusters_to_add;
+ u32 v_cpos = ocfs2_bytes_to_clusters(osb->sb, i_size_read(inode));
+ unsigned int num_clusters = 0;
+ unsigned int ext_flags = 0;
+ u32 size_div, offset_div;
+ int ret = 0;
+
+ {
+ u64 o = offset;
+ u64 s = i_size_read(inode);
+
+ offset_div = do_div(o, osb->s_clustersize);
+ size_div = do_div(s, osb->s_clustersize);
+ }
+
+ if (offset <= i_size_read(inode))
+ return 0;
+
+ clusters_to_add = ocfs2_bytes_to_clusters(inode->i_sb, offset) -
+ ocfs2_bytes_to_clusters(inode->i_sb, i_size_read(inode));
+ total_zero_len = offset - i_size_read(inode);
+ if (clusters_to_add)
+ total_zero_len -= offset_div;
+
+ /* Allocate clusters to fill out holes, and this is only needed
+ * when we add more than one clusters. Otherwise the cluster will
+ * be allocated during direct IO */
+ if (clusters_to_add > 1) {
+ ret = ocfs2_extend_allocation(inode,
+ OCFS2_I(inode)->ip_clusters,
+ clusters_to_add - 1, 0);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ while (total_zero_len) {
+ ret = ocfs2_get_clusters(inode, v_cpos, &p_cpos, &num_clusters,
+ &ext_flags);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ zero_start = ocfs2_clusters_to_bytes(osb->sb, p_cpos) +
+ size_div;
+ zero_len = ocfs2_clusters_to_bytes(osb->sb, num_clusters) -
+ size_div;
+ zero_len = min(total_zero_len, zero_len);
+
+ if (p_cpos && !(ext_flags & OCFS2_EXT_UNWRITTEN)) {
+ ret = blkdev_issue_zeroout(osb->sb->s_bdev,
+ zero_start >> 9, zero_len >> 9,
+ GFP_NOFS, false);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ total_zero_len -= zero_len;
+ v_cpos += ocfs2_bytes_to_clusters(osb->sb, zero_len + size_div);
+
+ /* Only at first iteration can be cluster not aligned.
+ * So set size_div to 0 for the rest */
+ size_div = 0;
+ }
+
+out:
+ return ret;
+}
+
+static ssize_t ocfs2_direct_IO_write(struct kiocb *iocb,
+ struct iov_iter *iter,
+ loff_t offset)
+{
+ ssize_t ret = 0;
+ ssize_t written = 0;
+ bool orphaned = false;
+ int is_overwrite = 0;
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file_inode(file)->i_mapping->host;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct buffer_head *di_bh = NULL;
+ size_t count = iter->count;
+ journal_t *journal = osb->journal->j_journal;
+ u64 zero_len_head, zero_len_tail;
+ int cluster_align_head, cluster_align_tail;
+ loff_t final_size = offset + count;
+ int append_write = offset >= i_size_read(inode) ? 1 : 0;
+ unsigned int num_clusters = 0;
+ unsigned int ext_flags = 0;
+
+ {
+ u64 o = offset;
+ u64 s = i_size_read(inode);
+
+ zero_len_head = do_div(o, 1 << osb->s_clustersize_bits);
+ cluster_align_head = !zero_len_head;
+
+ zero_len_tail = osb->s_clustersize -
+ do_div(s, osb->s_clustersize);
+ if ((offset - i_size_read(inode)) < zero_len_tail)
+ zero_len_tail = offset - i_size_read(inode);
+ cluster_align_tail = !zero_len_tail;
+ }
+
+ /*
+ * when final_size > inode->i_size, inode->i_size will be
+ * updated after direct write, so add the inode to orphan
+ * dir first.
+ */
+ if (final_size > i_size_read(inode)) {
+ ret = ocfs2_add_inode_to_orphan(osb, inode);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+ orphaned = true;
+ }
+
+ if (append_write) {
+ ret = ocfs2_inode_lock(inode, NULL, 1);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto clean_orphan;
+ }
+
+ /* zeroing out the previously allocated cluster tail
+ * that but not zeroed */
+ if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
+ ret = ocfs2_direct_IO_zero_extend(osb, inode, offset,
+ zero_len_tail, cluster_align_tail);
+ else
+ ret = ocfs2_direct_IO_extend_no_holes(osb, inode,
+ offset);
+ if (ret < 0) {
+ mlog_errno(ret);
+ ocfs2_inode_unlock(inode, 1);
+ goto clean_orphan;
+ }
+
+ is_overwrite = ocfs2_is_overwrite(osb, inode, offset);
+ if (is_overwrite < 0) {
+ mlog_errno(is_overwrite);
+ ocfs2_inode_unlock(inode, 1);
+ goto clean_orphan;
+ }
+
+ ocfs2_inode_unlock(inode, 1);
+ }
+
+ written = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, iter,
+ offset, ocfs2_direct_IO_get_blocks,
+ ocfs2_dio_end_io, NULL, 0);
+ if (unlikely(written < 0)) {
+ loff_t i_size = i_size_read(inode);
+
+ if (offset + count > i_size) {
+ ret = ocfs2_inode_lock(inode, &di_bh, 1);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto clean_orphan;
+ }
+
+ if (i_size == i_size_read(inode)) {
+ ret = ocfs2_truncate_file(inode, di_bh,
+ i_size);
+ if (ret < 0) {
+ if (ret != -ENOSPC)
+ mlog_errno(ret);
+
+ ocfs2_inode_unlock(inode, 1);
+ brelse(di_bh);
+ goto clean_orphan;
+ }
+ }
+
+ ocfs2_inode_unlock(inode, 1);
+ brelse(di_bh);
+
+ ret = jbd2_journal_force_commit(journal);
+ if (ret < 0)
+ mlog_errno(ret);
+ }
+ } else if (written > 0 && append_write && !is_overwrite &&
+ !cluster_align_head) {
+ /* zeroing out the allocated cluster head */
+ u32 p_cpos = 0;
+ u32 v_cpos = ocfs2_bytes_to_clusters(osb->sb, offset);
+
+ ret = ocfs2_inode_lock(inode, NULL, 0);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto clean_orphan;
+ }
+
+ ret = ocfs2_get_clusters(inode, v_cpos, &p_cpos,
+ &num_clusters, &ext_flags);
+ if (ret < 0) {
+ mlog_errno(ret);
+ ocfs2_inode_unlock(inode, 0);
+ goto clean_orphan;
+ }
+
+ BUG_ON(!p_cpos || (ext_flags & OCFS2_EXT_UNWRITTEN));
+
+ ret = blkdev_issue_zeroout(osb->sb->s_bdev,
+ p_cpos << (osb->s_clustersize_bits - 9),
+ zero_len_head >> 9, GFP_NOFS, false);
+ if (ret < 0)
+ mlog_errno(ret);
+
+ ocfs2_inode_unlock(inode, 0);
+ }
+
+clean_orphan:
+ if (orphaned) {
+ int tmp_ret;
+ int update_isize = written > 0 ? 1 : 0;
+ loff_t end = update_isize ? offset + written : 0;
+
+ tmp_ret = ocfs2_del_inode_from_orphan(osb, inode,
+ update_isize, end);
+ if (tmp_ret < 0) {
+ ret = tmp_ret;
+ goto out;
+ }
+
+ tmp_ret = jbd2_journal_force_commit(journal);
+ if (tmp_ret < 0) {
+ ret = tmp_ret;
+ mlog_errno(tmp_ret);
+ }
+ }
+
+out:
+ if (ret >= 0)
+ ret = written;
+ return ret;
+}
+
+static ssize_t ocfs2_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
+ loff_t offset)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file_inode(file)->i_mapping->host;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ int full_coherency = !(osb->s_mount_opt &
+ OCFS2_MOUNT_COHERENCY_BUFFERED);
+
+ /*
+ * Fallback to buffered I/O if we see an inode without
+ * extents.
+ */
+ if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+ return 0;
+
+ /* Fallback to buffered I/O if we are appending and
+ * concurrent O_DIRECT writes are allowed.
+ */
+ if (i_size_read(inode) <= offset && !full_coherency)
+ return 0;
+
+ if (iov_iter_rw(iter) == READ)
+ return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev,
+ iter, offset,
+ ocfs2_direct_IO_get_blocks,
+ ocfs2_dio_end_io, NULL, 0);
+ else
+ return ocfs2_direct_IO_write(iocb, iter, offset);
+}
+
+static void ocfs2_figure_cluster_boundaries(struct ocfs2_super *osb,
+ u32 cpos,
+ unsigned int *start,
+ unsigned int *end)
+{
+ unsigned int cluster_start = 0, cluster_end = PAGE_CACHE_SIZE;
+
+ if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits)) {
+ unsigned int cpp;
+
+ cpp = 1 << (PAGE_CACHE_SHIFT - osb->s_clustersize_bits);
+
+ cluster_start = cpos % cpp;
+ cluster_start = cluster_start << osb->s_clustersize_bits;
+
+ cluster_end = cluster_start + osb->s_clustersize;
+ }
+
+ BUG_ON(cluster_start > PAGE_SIZE);
+ BUG_ON(cluster_end > PAGE_SIZE);
+
+ if (start)
+ *start = cluster_start;
+ if (end)
+ *end = cluster_end;
+}
+
+/*
+ * 'from' and 'to' are the region in the page to avoid zeroing.
+ *
+ * If pagesize > clustersize, this function will avoid zeroing outside
+ * of the cluster boundary.
+ *
+ * from == to == 0 is code for "zero the entire cluster region"
+ */
+static void ocfs2_clear_page_regions(struct page *page,
+ struct ocfs2_super *osb, u32 cpos,
+ unsigned from, unsigned to)
+{
+ void *kaddr;
+ unsigned int cluster_start, cluster_end;
+
+ ocfs2_figure_cluster_boundaries(osb, cpos, &cluster_start, &cluster_end);
+
+ kaddr = kmap_atomic(page);
+
+ if (from || to) {
+ if (from > cluster_start)
+ memset(kaddr + cluster_start, 0, from - cluster_start);
+ if (to < cluster_end)
+ memset(kaddr + to, 0, cluster_end - to);
+ } else {
+ memset(kaddr + cluster_start, 0, cluster_end - cluster_start);
+ }
+
+ kunmap_atomic(kaddr);
+}
+
+/*
+ * Nonsparse file systems fully allocate before we get to the write
+ * code. This prevents ocfs2_write() from tagging the write as an
+ * allocating one, which means ocfs2_map_page_blocks() might try to
+ * read-in the blocks at the tail of our file. Avoid reading them by
+ * testing i_size against each block offset.
+ */
+static int ocfs2_should_read_blk(struct inode *inode, struct page *page,
+ unsigned int block_start)
+{
+ u64 offset = page_offset(page) + block_start;
+
+ if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
+ return 1;
+
+ if (i_size_read(inode) > offset)
+ return 1;
+
+ return 0;
+}
+
+/*
+ * Some of this taken from __block_write_begin(). We already have our
+ * mapping by now though, and the entire write will be allocating or
+ * it won't, so not much need to use BH_New.
+ *
+ * This will also skip zeroing, which is handled externally.
+ */
+int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
+ struct inode *inode, unsigned int from,
+ unsigned int to, int new)
+{
+ int ret = 0;
+ struct buffer_head *head, *bh, *wait[2], **wait_bh = wait;
+ unsigned int block_end, block_start;
+ unsigned int bsize = 1 << inode->i_blkbits;
+
+ if (!page_has_buffers(page))
+ create_empty_buffers(page, bsize, 0);
+
+ head = page_buffers(page);
+ for (bh = head, block_start = 0; bh != head || !block_start;
+ bh = bh->b_this_page, block_start += bsize) {
+ block_end = block_start + bsize;
+
+ clear_buffer_new(bh);
+
+ /*
+ * Ignore blocks outside of our i/o range -
+ * they may belong to unallocated clusters.
+ */
+ if (block_start >= to || block_end <= from) {
+ if (PageUptodate(page))
+ set_buffer_uptodate(bh);
+ continue;
+ }
+
+ /*
+ * For an allocating write with cluster size >= page
+ * size, we always write the entire page.
+ */
+ if (new)
+ set_buffer_new(bh);
+
+ if (!buffer_mapped(bh)) {
+ map_bh(bh, inode->i_sb, *p_blkno);
+ unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr);
+ }
+
+ if (PageUptodate(page)) {
+ if (!buffer_uptodate(bh))
+ set_buffer_uptodate(bh);
+ } else if (!buffer_uptodate(bh) && !buffer_delay(bh) &&
+ !buffer_new(bh) &&
+ ocfs2_should_read_blk(inode, page, block_start) &&
+ (block_start < from || block_end > to)) {
+ ll_rw_block(READ, 1, &bh);
+ *wait_bh++=bh;
+ }
+
+ *p_blkno = *p_blkno + 1;
+ }
+
+ /*
+ * If we issued read requests - let them complete.
+ */
+ while(wait_bh > wait) {
+ wait_on_buffer(*--wait_bh);
+ if (!buffer_uptodate(*wait_bh))
+ ret = -EIO;
+ }
+
+ if (ret == 0 || !new)
+ return ret;
+
+ /*
+ * If we get -EIO above, zero out any newly allocated blocks
+ * to avoid exposing stale data.
+ */
+ bh = head;
+ block_start = 0;
+ do {
+ block_end = block_start + bsize;
+ if (block_end <= from)
+ goto next_bh;
+ if (block_start >= to)
+ break;
+
+ zero_user(page, block_start, bh->b_size);
+ set_buffer_uptodate(bh);
+ mark_buffer_dirty(bh);
+
+next_bh:
+ block_start = block_end;
+ bh = bh->b_this_page;
+ } while (bh != head);
+
+ return ret;
+}
+
+#if (PAGE_CACHE_SIZE >= OCFS2_MAX_CLUSTERSIZE)
+#define OCFS2_MAX_CTXT_PAGES 1
+#else
+#define OCFS2_MAX_CTXT_PAGES (OCFS2_MAX_CLUSTERSIZE / PAGE_CACHE_SIZE)
+#endif
+
+#define OCFS2_MAX_CLUSTERS_PER_PAGE (PAGE_CACHE_SIZE / OCFS2_MIN_CLUSTERSIZE)
+
+/*
+ * Describe the state of a single cluster to be written to.
+ */
+struct ocfs2_write_cluster_desc {
+ u32 c_cpos;
+ u32 c_phys;
+ /*
+ * Give this a unique field because c_phys eventually gets
+ * filled.
+ */
+ unsigned c_new;
+ unsigned c_unwritten;
+ unsigned c_needs_zero;
+};
+
+struct ocfs2_write_ctxt {
+ /* Logical cluster position / len of write */
+ u32 w_cpos;
+ u32 w_clen;
+
+ /* First cluster allocated in a nonsparse extend */
+ u32 w_first_new_cpos;
+
+ struct ocfs2_write_cluster_desc w_desc[OCFS2_MAX_CLUSTERS_PER_PAGE];
+
+ /*
+ * This is true if page_size > cluster_size.
+ *
+ * It triggers a set of special cases during write which might
+ * have to deal with allocating writes to partial pages.
+ */
+ unsigned int w_large_pages;
+
+ /*
+ * Pages involved in this write.
+ *
+ * w_target_page is the page being written to by the user.
+ *
+ * w_pages is an array of pages which always contains
+ * w_target_page, and in the case of an allocating write with
+ * page_size < cluster size, it will contain zero'd and mapped
+ * pages adjacent to w_target_page which need to be written
+ * out in so that future reads from that region will get
+ * zero's.
+ */
+ unsigned int w_num_pages;
+ struct page *w_pages[OCFS2_MAX_CTXT_PAGES];
+ struct page *w_target_page;
+
+ /*
+ * w_target_locked is used for page_mkwrite path indicating no unlocking
+ * against w_target_page in ocfs2_write_end_nolock.
+ */
+ unsigned int w_target_locked:1;
+
+ /*
+ * ocfs2_write_end() uses this to know what the real range to
+ * write in the target should be.
+ */
+ unsigned int w_target_from;
+ unsigned int w_target_to;
+
+ /*
+ * We could use journal_current_handle() but this is cleaner,
+ * IMHO -Mark
+ */
+ handle_t *w_handle;
+
+ struct buffer_head *w_di_bh;
+
+ struct ocfs2_cached_dealloc_ctxt w_dealloc;
+};
+
+void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages)
+{
+ int i;
+
+ for(i = 0; i < num_pages; i++) {
+ if (pages[i]) {
+ unlock_page(pages[i]);
+ mark_page_accessed(pages[i]);
+ page_cache_release(pages[i]);
+ }
+ }
+}
+
+static void ocfs2_unlock_pages(struct ocfs2_write_ctxt *wc)
+{
+ int i;
+
+ /*
+ * w_target_locked is only set to true in the page_mkwrite() case.
+ * The intent is to allow us to lock the target page from write_begin()
+ * to write_end(). The caller must hold a ref on w_target_page.
+ */
+ if (wc->w_target_locked) {
+ BUG_ON(!wc->w_target_page);
+ for (i = 0; i < wc->w_num_pages; i++) {
+ if (wc->w_target_page == wc->w_pages[i]) {
+ wc->w_pages[i] = NULL;
+ break;
+ }
+ }
+ mark_page_accessed(wc->w_target_page);
+ page_cache_release(wc->w_target_page);
+ }
+ ocfs2_unlock_and_free_pages(wc->w_pages, wc->w_num_pages);
+}
+
+static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc)
+{
+ ocfs2_unlock_pages(wc);
+ brelse(wc->w_di_bh);
+ kfree(wc);
+}
+
+static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
+ struct ocfs2_super *osb, loff_t pos,
+ unsigned len, struct buffer_head *di_bh)
+{
+ u32 cend;
+ struct ocfs2_write_ctxt *wc;
+
+ wc = kzalloc(sizeof(struct ocfs2_write_ctxt), GFP_NOFS);
+ if (!wc)
+ return -ENOMEM;
+
+ wc->w_cpos = pos >> osb->s_clustersize_bits;
+ wc->w_first_new_cpos = UINT_MAX;
+ cend = (pos + len - 1) >> osb->s_clustersize_bits;
+ wc->w_clen = cend - wc->w_cpos + 1;
+ get_bh(di_bh);
+ wc->w_di_bh = di_bh;
+
+ if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits))
+ wc->w_large_pages = 1;
+ else
+ wc->w_large_pages = 0;
+
+ ocfs2_init_dealloc_ctxt(&wc->w_dealloc);
+
+ *wcp = wc;
+
+ return 0;
+}
+
+/*
+ * If a page has any new buffers, zero them out here, and mark them uptodate
+ * and dirty so they'll be written out (in order to prevent uninitialised
+ * block data from leaking). And clear the new bit.
+ */
+static void ocfs2_zero_new_buffers(struct page *page, unsigned from, unsigned to)
+{
+ unsigned int block_start, block_end;
+ struct buffer_head *head, *bh;
+
+ BUG_ON(!PageLocked(page));
+ if (!page_has_buffers(page))
+ return;
+
+ bh = head = page_buffers(page);
+ block_start = 0;
+ do {
+ block_end = block_start + bh->b_size;
+
+ if (buffer_new(bh)) {
+ if (block_end > from && block_start < to) {
+ if (!PageUptodate(page)) {
+ unsigned start, end;
+
+ start = max(from, block_start);
+ end = min(to, block_end);
+
+ zero_user_segment(page, start, end);
+ set_buffer_uptodate(bh);
+ }
+
+ clear_buffer_new(bh);
+ mark_buffer_dirty(bh);
+ }
+ }
+
+ block_start = block_end;
+ bh = bh->b_this_page;
+ } while (bh != head);
+}
+
+/*
+ * Only called when we have a failure during allocating write to write
+ * zero's to the newly allocated region.
+ */
+static void ocfs2_write_failure(struct inode *inode,
+ struct ocfs2_write_ctxt *wc,
+ loff_t user_pos, unsigned user_len)
+{
+ int i;
+ unsigned from = user_pos & (PAGE_CACHE_SIZE - 1),
+ to = user_pos + user_len;
+ struct page *tmppage;
+
+ ocfs2_zero_new_buffers(wc->w_target_page, from, to);
+
+ for(i = 0; i < wc->w_num_pages; i++) {
+ tmppage = wc->w_pages[i];
+
+ if (page_has_buffers(tmppage)) {
+ if (ocfs2_should_order_data(inode))
+ ocfs2_jbd2_file_inode(wc->w_handle, inode);
+
+ block_commit_write(tmppage, from, to);
+ }
+ }
+}
+
+static int ocfs2_prepare_page_for_write(struct inode *inode, u64 *p_blkno,
+ struct ocfs2_write_ctxt *wc,
+ struct page *page, u32 cpos,
+ loff_t user_pos, unsigned user_len,
+ int new)
+{
+ int ret;
+ unsigned int map_from = 0, map_to = 0;
+ unsigned int cluster_start, cluster_end;
+ unsigned int user_data_from = 0, user_data_to = 0;
+
+ ocfs2_figure_cluster_boundaries(OCFS2_SB(inode->i_sb), cpos,
+ &cluster_start, &cluster_end);
+
+ /* treat the write as new if the a hole/lseek spanned across
+ * the page boundary.
+ */
+ new = new | ((i_size_read(inode) <= page_offset(page)) &&
+ (page_offset(page) <= user_pos));
+
+ if (page == wc->w_target_page) {
+ map_from = user_pos & (PAGE_CACHE_SIZE - 1);
+ map_to = map_from + user_len;
+
+ if (new)
+ ret = ocfs2_map_page_blocks(page, p_blkno, inode,
+ cluster_start, cluster_end,
+ new);
+ else
+ ret = ocfs2_map_page_blocks(page, p_blkno, inode,
+ map_from, map_to, new);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ user_data_from = map_from;
+ user_data_to = map_to;
+ if (new) {
+ map_from = cluster_start;
+ map_to = cluster_end;
+ }
+ } else {
+ /*
+ * If we haven't allocated the new page yet, we
+ * shouldn't be writing it out without copying user
+ * data. This is likely a math error from the caller.
+ */
+ BUG_ON(!new);
+
+ map_from = cluster_start;
+ map_to = cluster_end;
+
+ ret = ocfs2_map_page_blocks(page, p_blkno, inode,
+ cluster_start, cluster_end, new);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ /*
+ * Parts of newly allocated pages need to be zero'd.
+ *
+ * Above, we have also rewritten 'to' and 'from' - as far as
+ * the rest of the function is concerned, the entire cluster
+ * range inside of a page needs to be written.
+ *
+ * We can skip this if the page is up to date - it's already
+ * been zero'd from being read in as a hole.
+ */
+ if (new && !PageUptodate(page))
+ ocfs2_clear_page_regions(page, OCFS2_SB(inode->i_sb),
+ cpos, user_data_from, user_data_to);
+
+ flush_dcache_page(page);
+
+out:
+ return ret;
+}
+
+/*
+ * This function will only grab one clusters worth of pages.
+ */
+static int ocfs2_grab_pages_for_write(struct address_space *mapping,
+ struct ocfs2_write_ctxt *wc,
+ u32 cpos, loff_t user_pos,
+ unsigned user_len, int new,
+ struct page *mmap_page)
+{
+ int ret = 0, i;
+ unsigned long start, target_index, end_index, index;
+ struct inode *inode = mapping->host;
+ loff_t last_byte;
+
+ target_index = user_pos >> PAGE_CACHE_SHIFT;
+
+ /*
+ * Figure out how many pages we'll be manipulating here. For
+ * non allocating write, we just change the one
+ * page. Otherwise, we'll need a whole clusters worth. If we're
+ * writing past i_size, we only need enough pages to cover the
+ * last page of the write.
+ */
+ if (new) {
+ wc->w_num_pages = ocfs2_pages_per_cluster(inode->i_sb);
+ start = ocfs2_align_clusters_to_page_index(inode->i_sb, cpos);
+ /*
+ * We need the index *past* the last page we could possibly
+ * touch. This is the page past the end of the write or
+ * i_size, whichever is greater.
+ */
+ last_byte = max(user_pos + user_len, i_size_read(inode));
+ BUG_ON(last_byte < 1);
+ end_index = ((last_byte - 1) >> PAGE_CACHE_SHIFT) + 1;
+ if ((start + wc->w_num_pages) > end_index)
+ wc->w_num_pages = end_index - start;
+ } else {
+ wc->w_num_pages = 1;
+ start = target_index;
+ }
+
+ for(i = 0; i < wc->w_num_pages; i++) {
+ index = start + i;
+
+ if (index == target_index && mmap_page) {
+ /*
+ * ocfs2_pagemkwrite() is a little different
+ * and wants us to directly use the page
+ * passed in.
+ */
+ lock_page(mmap_page);
+
+ /* Exit and let the caller retry */
+ if (mmap_page->mapping != mapping) {
+ WARN_ON(mmap_page->mapping);
+ unlock_page(mmap_page);
+ ret = -EAGAIN;
+ goto out;
+ }
+
+ page_cache_get(mmap_page);
+ wc->w_pages[i] = mmap_page;
+ wc->w_target_locked = true;
+ } else {
+ wc->w_pages[i] = find_or_create_page(mapping, index,
+ GFP_NOFS);
+ if (!wc->w_pages[i]) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+ wait_for_stable_page(wc->w_pages[i]);
+
+ if (index == target_index)
+ wc->w_target_page = wc->w_pages[i];
+ }
+out:
+ if (ret)
+ wc->w_target_locked = false;
+ return ret;
+}
+
+/*
+ * Prepare a single cluster for write one cluster into the file.
+ */
+static int ocfs2_write_cluster(struct address_space *mapping,
+ u32 phys, unsigned int unwritten,
+ unsigned int should_zero,
+ struct ocfs2_alloc_context *data_ac,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_write_ctxt *wc, u32 cpos,
+ loff_t user_pos, unsigned user_len)
+{
+ int ret, i, new;
+ u64 v_blkno, p_blkno;
+ struct inode *inode = mapping->host;
+ struct ocfs2_extent_tree et;
+
+ new = phys == 0 ? 1 : 0;
+ if (new) {
+ u32 tmp_pos;
+
+ /*
+ * This is safe to call with the page locks - it won't take
+ * any additional semaphores or cluster locks.
+ */
+ tmp_pos = cpos;
+ ret = ocfs2_add_inode_data(OCFS2_SB(inode->i_sb), inode,
+ &tmp_pos, 1, 0, wc->w_di_bh,
+ wc->w_handle, data_ac,
+ meta_ac, NULL);
+ /*
+ * This shouldn't happen because we must have already
+ * calculated the correct meta data allocation required. The
+ * internal tree allocation code should know how to increase
+ * transaction credits itself.
+ *
+ * If need be, we could handle -EAGAIN for a
+ * RESTART_TRANS here.
+ */
+ mlog_bug_on_msg(ret == -EAGAIN,
+ "Inode %llu: EAGAIN return during allocation.\n",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+ } else if (unwritten) {
+ ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode),
+ wc->w_di_bh);
+ ret = ocfs2_mark_extent_written(inode, &et,
+ wc->w_handle, cpos, 1, phys,
+ meta_ac, &wc->w_dealloc);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ if (should_zero)
+ v_blkno = ocfs2_clusters_to_blocks(inode->i_sb, cpos);
+ else
+ v_blkno = user_pos >> inode->i_sb->s_blocksize_bits;
+
+ /*
+ * The only reason this should fail is due to an inability to
+ * find the extent added.
+ */
+ ret = ocfs2_extent_map_get_blocks(inode, v_blkno, &p_blkno, NULL,
+ NULL);
+ if (ret < 0) {
+ mlog(ML_ERROR, "Get physical blkno failed for inode %llu, "
+ "at logical block %llu",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)v_blkno);
+ goto out;
+ }
+
+ BUG_ON(p_blkno == 0);
+
+ for(i = 0; i < wc->w_num_pages; i++) {
+ int tmpret;
+
+ tmpret = ocfs2_prepare_page_for_write(inode, &p_blkno, wc,
+ wc->w_pages[i], cpos,
+ user_pos, user_len,
+ should_zero);
+ if (tmpret) {
+ mlog_errno(tmpret);
+ if (ret == 0)
+ ret = tmpret;
+ }
+ }
+
+ /*
+ * We only have cleanup to do in case of allocating write.
+ */
+ if (ret && new)
+ ocfs2_write_failure(inode, wc, user_pos, user_len);
+
+out:
+
+ return ret;
+}
+
+static int ocfs2_write_cluster_by_desc(struct address_space *mapping,
+ struct ocfs2_alloc_context *data_ac,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_write_ctxt *wc,
+ loff_t pos, unsigned len)
+{
+ int ret, i;
+ loff_t cluster_off;
+ unsigned int local_len = len;
+ struct ocfs2_write_cluster_desc *desc;
+ struct ocfs2_super *osb = OCFS2_SB(mapping->host->i_sb);
+
+ for (i = 0; i < wc->w_clen; i++) {
+ desc = &wc->w_desc[i];
+
+ /*
+ * We have to make sure that the total write passed in
+ * doesn't extend past a single cluster.
+ */
+ local_len = len;
+ cluster_off = pos & (osb->s_clustersize - 1);
+ if ((cluster_off + local_len) > osb->s_clustersize)
+ local_len = osb->s_clustersize - cluster_off;
+
+ ret = ocfs2_write_cluster(mapping, desc->c_phys,
+ desc->c_unwritten,
+ desc->c_needs_zero,
+ data_ac, meta_ac,
+ wc, desc->c_cpos, pos, local_len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ len -= local_len;
+ pos += local_len;
+ }
+
+ ret = 0;
+out:
+ return ret;
+}
+
+/*
+ * ocfs2_write_end() wants to know which parts of the target page it
+ * should complete the write on. It's easiest to compute them ahead of
+ * time when a more complete view of the write is available.
+ */
+static void ocfs2_set_target_boundaries(struct ocfs2_super *osb,
+ struct ocfs2_write_ctxt *wc,
+ loff_t pos, unsigned len, int alloc)
+{
+ struct ocfs2_write_cluster_desc *desc;
+
+ wc->w_target_from = pos & (PAGE_CACHE_SIZE - 1);
+ wc->w_target_to = wc->w_target_from + len;
+
+ if (alloc == 0)
+ return;
+
+ /*
+ * Allocating write - we may have different boundaries based
+ * on page size and cluster size.
+ *
+ * NOTE: We can no longer compute one value from the other as
+ * the actual write length and user provided length may be
+ * different.
+ */
+
+ if (wc->w_large_pages) {
+ /*
+ * We only care about the 1st and last cluster within
+ * our range and whether they should be zero'd or not. Either
+ * value may be extended out to the start/end of a
+ * newly allocated cluster.
+ */
+ desc = &wc->w_desc[0];
+ if (desc->c_needs_zero)
+ ocfs2_figure_cluster_boundaries(osb,
+ desc->c_cpos,
+ &wc->w_target_from,
+ NULL);
+
+ desc = &wc->w_desc[wc->w_clen - 1];
+ if (desc->c_needs_zero)
+ ocfs2_figure_cluster_boundaries(osb,
+ desc->c_cpos,
+ NULL,
+ &wc->w_target_to);
+ } else {
+ wc->w_target_from = 0;
+ wc->w_target_to = PAGE_CACHE_SIZE;
+ }
+}
+
+/*
+ * Populate each single-cluster write descriptor in the write context
+ * with information about the i/o to be done.
+ *
+ * Returns the number of clusters that will have to be allocated, as
+ * well as a worst case estimate of the number of extent records that
+ * would have to be created during a write to an unwritten region.
+ */
+static int ocfs2_populate_write_desc(struct inode *inode,
+ struct ocfs2_write_ctxt *wc,
+ unsigned int *clusters_to_alloc,
+ unsigned int *extents_to_split)
+{
+ int ret;
+ struct ocfs2_write_cluster_desc *desc;
+ unsigned int num_clusters = 0;
+ unsigned int ext_flags = 0;
+ u32 phys = 0;
+ int i;
+
+ *clusters_to_alloc = 0;
+ *extents_to_split = 0;
+
+ for (i = 0; i < wc->w_clen; i++) {
+ desc = &wc->w_desc[i];
+ desc->c_cpos = wc->w_cpos + i;
+
+ if (num_clusters == 0) {
+ /*
+ * Need to look up the next extent record.
+ */
+ ret = ocfs2_get_clusters(inode, desc->c_cpos, &phys,
+ &num_clusters, &ext_flags);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /* We should already CoW the refcountd extent. */
+ BUG_ON(ext_flags & OCFS2_EXT_REFCOUNTED);
+
+ /*
+ * Assume worst case - that we're writing in
+ * the middle of the extent.
+ *
+ * We can assume that the write proceeds from
+ * left to right, in which case the extent
+ * insert code is smart enough to coalesce the
+ * next splits into the previous records created.
+ */
+ if (ext_flags & OCFS2_EXT_UNWRITTEN)
+ *extents_to_split = *extents_to_split + 2;
+ } else if (phys) {
+ /*
+ * Only increment phys if it doesn't describe
+ * a hole.
+ */
+ phys++;
+ }
+
+ /*
+ * If w_first_new_cpos is < UINT_MAX, we have a non-sparse
+ * file that got extended. w_first_new_cpos tells us
+ * where the newly allocated clusters are so we can
+ * zero them.
+ */
+ if (desc->c_cpos >= wc->w_first_new_cpos) {
+ BUG_ON(phys == 0);
+ desc->c_needs_zero = 1;
+ }
+
+ desc->c_phys = phys;
+ if (phys == 0) {
+ desc->c_new = 1;
+ desc->c_needs_zero = 1;
+ *clusters_to_alloc = *clusters_to_alloc + 1;
+ }
+
+ if (ext_flags & OCFS2_EXT_UNWRITTEN) {
+ desc->c_unwritten = 1;
+ desc->c_needs_zero = 1;
+ }
+
+ num_clusters--;
+ }
+
+ ret = 0;
+out:
+ return ret;
+}
+
+static int ocfs2_write_begin_inline(struct address_space *mapping,
+ struct inode *inode,
+ struct ocfs2_write_ctxt *wc)
+{
+ int ret;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct page *page;
+ handle_t *handle;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
+
+ handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ page = find_or_create_page(mapping, 0, GFP_NOFS);
+ if (!page) {
+ ocfs2_commit_trans(osb, handle);
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+ /*
+ * If we don't set w_num_pages then this page won't get unlocked
+ * and freed on cleanup of the write context.
+ */
+ wc->w_pages[0] = wc->w_target_page = page;
+ wc->w_num_pages = 1;
+
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ ocfs2_commit_trans(osb, handle);
+
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL))
+ ocfs2_set_inode_data_inline(inode, di);
+
+ if (!PageUptodate(page)) {
+ ret = ocfs2_read_inline_data(inode, page, wc->w_di_bh);
+ if (ret) {
+ ocfs2_commit_trans(osb, handle);
+
+ goto out;
+ }
+ }
+
+ wc->w_handle = handle;
+out:
+ return ret;
+}
+
+int ocfs2_size_fits_inline_data(struct buffer_head *di_bh, u64 new_size)
+{
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+
+ if (new_size <= le16_to_cpu(di->id2.i_data.id_count))
+ return 1;
+ return 0;
+}
+
+static int ocfs2_try_to_write_inline_data(struct address_space *mapping,
+ struct inode *inode, loff_t pos,
+ unsigned len, struct page *mmap_page,
+ struct ocfs2_write_ctxt *wc)
+{
+ int ret, written = 0;
+ loff_t end = pos + len;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_dinode *di = NULL;
+
+ trace_ocfs2_try_to_write_inline_data((unsigned long long)oi->ip_blkno,
+ len, (unsigned long long)pos,
+ oi->ip_dyn_features);
+
+ /*
+ * Handle inodes which already have inline data 1st.
+ */
+ if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+ if (mmap_page == NULL &&
+ ocfs2_size_fits_inline_data(wc->w_di_bh, end))
+ goto do_inline_write;
+
+ /*
+ * The write won't fit - we have to give this inode an
+ * inline extent list now.
+ */
+ ret = ocfs2_convert_inline_data_to_extents(inode, wc->w_di_bh);
+ if (ret)
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /*
+ * Check whether the inode can accept inline data.
+ */
+ if (oi->ip_clusters != 0 || i_size_read(inode) != 0)
+ return 0;
+
+ /*
+ * Check whether the write can fit.
+ */
+ di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
+ if (mmap_page ||
+ end > ocfs2_max_inline_data_with_xattr(inode->i_sb, di))
+ return 0;
+
+do_inline_write:
+ ret = ocfs2_write_begin_inline(mapping, inode, wc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /*
+ * This signals to the caller that the data can be written
+ * inline.
+ */
+ written = 1;
+out:
+ return written ? written : ret;
+}
+
+/*
+ * This function only does anything for file systems which can't
+ * handle sparse files.
+ *
+ * What we want to do here is fill in any hole between the current end
+ * of allocation and the end of our write. That way the rest of the
+ * write path can treat it as an non-allocating write, which has no
+ * special case code for sparse/nonsparse files.
+ */
+static int ocfs2_expand_nonsparse_inode(struct inode *inode,
+ struct buffer_head *di_bh,
+ loff_t pos, unsigned len,
+ struct ocfs2_write_ctxt *wc)
+{
+ int ret;
+ loff_t newsize = pos + len;
+
+ BUG_ON(ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)));
+
+ if (newsize <= i_size_read(inode))
+ return 0;
+
+ ret = ocfs2_extend_no_holes(inode, di_bh, newsize, pos);
+ if (ret)
+ mlog_errno(ret);
+
+ wc->w_first_new_cpos =
+ ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode));
+
+ return ret;
+}
+
+static int ocfs2_zero_tail(struct inode *inode, struct buffer_head *di_bh,
+ loff_t pos)
+{
+ int ret = 0;
+
+ BUG_ON(!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)));
+ if (pos > i_size_read(inode))
+ ret = ocfs2_zero_extend(inode, di_bh, pos);
+
+ return ret;
+}
+
+/*
+ * Try to flush truncate logs if we can free enough clusters from it.
+ * As for return value, "< 0" means error, "0" no space and "1" means
+ * we have freed enough spaces and let the caller try to allocate again.
+ */
+static int ocfs2_try_to_free_truncate_log(struct ocfs2_super *osb,
+ unsigned int needed)
+{
+ tid_t target;
+ int ret = 0;
+ unsigned int truncated_clusters;
+
+ mutex_lock(&osb->osb_tl_inode->i_mutex);
+ truncated_clusters = osb->truncated_clusters;
+ mutex_unlock(&osb->osb_tl_inode->i_mutex);
+
+ /*
+ * Check whether we can succeed in allocating if we free
+ * the truncate log.
+ */
+ if (truncated_clusters < needed)
+ goto out;
+
+ ret = ocfs2_flush_truncate_log(osb);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (jbd2_journal_start_commit(osb->journal->j_journal, &target)) {
+ jbd2_log_wait_commit(osb->journal->j_journal, target);
+ ret = 1;
+ }
+out:
+ return ret;
+}
+
+int ocfs2_write_begin_nolock(struct file *filp,
+ struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata,
+ struct buffer_head *di_bh, struct page *mmap_page)
+{
+ int ret, cluster_of_pages, credits = OCFS2_INODE_UPDATE_CREDITS;
+ unsigned int clusters_to_alloc, extents_to_split, clusters_need = 0;
+ struct ocfs2_write_ctxt *wc;
+ struct inode *inode = mapping->host;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_dinode *di;
+ struct ocfs2_alloc_context *data_ac = NULL;
+ struct ocfs2_alloc_context *meta_ac = NULL;
+ handle_t *handle;
+ struct ocfs2_extent_tree et;
+ int try_free = 1, ret1;
+
+try_again:
+ ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, di_bh);
+ if (ret) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ if (ocfs2_supports_inline_data(osb)) {
+ ret = ocfs2_try_to_write_inline_data(mapping, inode, pos, len,
+ mmap_page, wc);
+ if (ret == 1) {
+ ret = 0;
+ goto success;
+ }
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ if (ocfs2_sparse_alloc(osb))
+ ret = ocfs2_zero_tail(inode, di_bh, pos);
+ else
+ ret = ocfs2_expand_nonsparse_inode(inode, di_bh, pos, len,
+ wc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_check_range_for_refcount(inode, pos, len);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ } else if (ret == 1) {
+ clusters_need = wc->w_clen;
+ ret = ocfs2_refcount_cow(inode, di_bh,
+ wc->w_cpos, wc->w_clen, UINT_MAX);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ ret = ocfs2_populate_write_desc(inode, wc, &clusters_to_alloc,
+ &extents_to_split);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ clusters_need += clusters_to_alloc;
+
+ di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
+
+ trace_ocfs2_write_begin_nolock(
+ (unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (long long)i_size_read(inode),
+ le32_to_cpu(di->i_clusters),
+ pos, len, flags, mmap_page,
+ clusters_to_alloc, extents_to_split);
+
+ /*
+ * We set w_target_from, w_target_to here so that
+ * ocfs2_write_end() knows which range in the target page to
+ * write out. An allocation requires that we write the entire
+ * cluster range.
+ */
+ if (clusters_to_alloc || extents_to_split) {
+ /*
+ * XXX: We are stretching the limits of
+ * ocfs2_lock_allocators(). It greatly over-estimates
+ * the work to be done.
+ */
+ ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode),
+ wc->w_di_bh);
+ ret = ocfs2_lock_allocators(inode, &et,
+ clusters_to_alloc, extents_to_split,
+ &data_ac, &meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (data_ac)
+ data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
+
+ credits = ocfs2_calc_extend_credits(inode->i_sb,
+ &di->id2.i_list);
+
+ }
+
+ /*
+ * We have to zero sparse allocated clusters, unwritten extent clusters,
+ * and non-sparse clusters we just extended. For non-sparse writes,
+ * we know zeros will only be needed in the first and/or last cluster.
+ */
+ if (clusters_to_alloc || extents_to_split ||
+ (wc->w_clen && (wc->w_desc[0].c_needs_zero ||
+ wc->w_desc[wc->w_clen - 1].c_needs_zero)))
+ cluster_of_pages = 1;
+ else
+ cluster_of_pages = 0;
+
+ ocfs2_set_target_boundaries(osb, wc, pos, len, cluster_of_pages);
+
+ handle = ocfs2_start_trans(osb, credits);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ wc->w_handle = handle;
+
+ if (clusters_to_alloc) {
+ ret = dquot_alloc_space_nodirty(inode,
+ ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc));
+ if (ret)
+ goto out_commit;
+ }
+ /*
+ * We don't want this to fail in ocfs2_write_end(), so do it
+ * here.
+ */
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_quota;
+ }
+
+ /*
+ * Fill our page array first. That way we've grabbed enough so
+ * that we can zero and flush if we error after adding the
+ * extent.
+ */
+ ret = ocfs2_grab_pages_for_write(mapping, wc, wc->w_cpos, pos, len,
+ cluster_of_pages, mmap_page);
+ if (ret && ret != -EAGAIN) {
+ mlog_errno(ret);
+ goto out_quota;
+ }
+
+ /*
+ * ocfs2_grab_pages_for_write() returns -EAGAIN if it could not lock
+ * the target page. In this case, we exit with no error and no target
+ * page. This will trigger the caller, page_mkwrite(), to re-try
+ * the operation.
+ */
+ if (ret == -EAGAIN) {
+ BUG_ON(wc->w_target_page);
+ ret = 0;
+ goto out_quota;
+ }
+
+ ret = ocfs2_write_cluster_by_desc(mapping, data_ac, meta_ac, wc, pos,
+ len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_quota;
+ }
+
+ if (data_ac)
+ ocfs2_free_alloc_context(data_ac);
+ if (meta_ac)
+ ocfs2_free_alloc_context(meta_ac);
+
+success:
+ *pagep = wc->w_target_page;
+ *fsdata = wc;
+ return 0;
+out_quota:
+ if (clusters_to_alloc)
+ dquot_free_space(inode,
+ ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc));
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+
+out:
+ ocfs2_free_write_ctxt(wc);
+
+ if (data_ac) {
+ ocfs2_free_alloc_context(data_ac);
+ data_ac = NULL;
+ }
+ if (meta_ac) {
+ ocfs2_free_alloc_context(meta_ac);
+ meta_ac = NULL;
+ }
+
+ if (ret == -ENOSPC && try_free) {
+ /*
+ * Try to free some truncate log so that we can have enough
+ * clusters to allocate.
+ */
+ try_free = 0;
+
+ ret1 = ocfs2_try_to_free_truncate_log(osb, clusters_need);
+ if (ret1 == 1)
+ goto try_again;
+
+ if (ret1 < 0)
+ mlog_errno(ret1);
+ }
+
+ return ret;
+}
+
+static int ocfs2_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
+{
+ int ret;
+ struct buffer_head *di_bh = NULL;
+ struct inode *inode = mapping->host;
+
+ ret = ocfs2_inode_lock(inode, &di_bh, 1);
+ if (ret) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ /*
+ * Take alloc sem here to prevent concurrent lookups. That way
+ * the mapping, zeroing and tree manipulation within
+ * ocfs2_write() will be safe against ->readpage(). This
+ * should also serve to lock out allocation from a shared
+ * writeable region.
+ */
+ down_write(&OCFS2_I(inode)->ip_alloc_sem);
+
+ ret = ocfs2_write_begin_nolock(file, mapping, pos, len, flags, pagep,
+ fsdata, di_bh, NULL);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_fail;
+ }
+
+ brelse(di_bh);
+
+ return 0;
+
+out_fail:
+ up_write(&OCFS2_I(inode)->ip_alloc_sem);
+
+ brelse(di_bh);
+ ocfs2_inode_unlock(inode, 1);
+
+ return ret;
+}
+
+static void ocfs2_write_end_inline(struct inode *inode, loff_t pos,
+ unsigned len, unsigned *copied,
+ struct ocfs2_dinode *di,
+ struct ocfs2_write_ctxt *wc)
+{
+ void *kaddr;
+
+ if (unlikely(*copied < len)) {
+ if (!PageUptodate(wc->w_target_page)) {
+ *copied = 0;
+ return;
+ }
+ }
+
+ kaddr = kmap_atomic(wc->w_target_page);
+ memcpy(di->id2.i_data.id_data + pos, kaddr + pos, *copied);
+ kunmap_atomic(kaddr);
+
+ trace_ocfs2_write_end_inline(
+ (unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)pos, *copied,
+ le16_to_cpu(di->id2.i_data.id_count),
+ le16_to_cpu(di->i_dyn_features));
+}
+
+int ocfs2_write_end_nolock(struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
+{
+ int i;
+ unsigned from, to, start = pos & (PAGE_CACHE_SIZE - 1);
+ struct inode *inode = mapping->host;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_write_ctxt *wc = fsdata;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
+ handle_t *handle = wc->w_handle;
+ struct page *tmppage;
+
+ if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+ ocfs2_write_end_inline(inode, pos, len, &copied, di, wc);
+ goto out_write_size;
+ }
+
+ if (unlikely(copied < len)) {
+ if (!PageUptodate(wc->w_target_page))
+ copied = 0;
+
+ ocfs2_zero_new_buffers(wc->w_target_page, start+copied,
+ start+len);
+ }
+ flush_dcache_page(wc->w_target_page);
+
+ for(i = 0; i < wc->w_num_pages; i++) {
+ tmppage = wc->w_pages[i];
+
+ if (tmppage == wc->w_target_page) {
+ from = wc->w_target_from;
+ to = wc->w_target_to;
+
+ BUG_ON(from > PAGE_CACHE_SIZE ||
+ to > PAGE_CACHE_SIZE ||
+ to < from);
+ } else {
+ /*
+ * Pages adjacent to the target (if any) imply
+ * a hole-filling write in which case we want
+ * to flush their entire range.
+ */
+ from = 0;
+ to = PAGE_CACHE_SIZE;
+ }
+
+ if (page_has_buffers(tmppage)) {
+ if (ocfs2_should_order_data(inode))
+ ocfs2_jbd2_file_inode(wc->w_handle, inode);
+ block_commit_write(tmppage, from, to);
+ }
+ }
+
+out_write_size:
+ pos += copied;
+ if (pos > i_size_read(inode)) {
+ i_size_write(inode, pos);
+ mark_inode_dirty(inode);
+ }
+ inode->i_blocks = ocfs2_inode_sector_count(inode);
+ di->i_size = cpu_to_le64((u64)i_size_read(inode));
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ di->i_mtime = di->i_ctime = cpu_to_le64(inode->i_mtime.tv_sec);
+ di->i_mtime_nsec = di->i_ctime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
+ ocfs2_update_inode_fsync_trans(handle, inode, 1);
+ ocfs2_journal_dirty(handle, wc->w_di_bh);
+
+ /* unlock pages before dealloc since it needs acquiring j_trans_barrier
+ * lock, or it will cause a deadlock since journal commit threads holds
+ * this lock and will ask for the page lock when flushing the data.
+ * put it here to preserve the unlock order.
+ */
+ ocfs2_unlock_pages(wc);
+
+ ocfs2_commit_trans(osb, handle);
+
+ ocfs2_run_deallocs(osb, &wc->w_dealloc);
+
+ brelse(wc->w_di_bh);
+ kfree(wc);
+
+ return copied;
+}
+
+static int ocfs2_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
+{
+ int ret;
+ struct inode *inode = mapping->host;
+
+ ret = ocfs2_write_end_nolock(mapping, pos, len, copied, page, fsdata);
+
+ up_write(&OCFS2_I(inode)->ip_alloc_sem);
+ ocfs2_inode_unlock(inode, 1);
+
+ return ret;
+}
+
+const struct address_space_operations ocfs2_aops = {
+ .readpage = ocfs2_readpage,
+ .readpages = ocfs2_readpages,
+ .writepage = ocfs2_writepage,
+ .write_begin = ocfs2_write_begin,
+ .write_end = ocfs2_write_end,
+ .bmap = ocfs2_bmap,
+ .direct_IO = ocfs2_direct_IO,
+ .invalidatepage = block_invalidatepage,
+ .releasepage = ocfs2_releasepage,
+ .migratepage = buffer_migrate_page,
+ .is_partially_uptodate = block_is_partially_uptodate,
+ .error_remove_page = generic_error_remove_page,
+};
Code Review / kvmfornfv.git / blobdiff