diff options
| -rw-r--r-- | fs/xfs/xfs_aops.c | 173 |
1 files changed, 127 insertions, 46 deletions
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 139e495..392833c 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -1187,11 +1187,18 @@ __xfs_get_blocks( &imap, nimaps); if (error) return -error; + new = 1; } else { /* * Delalloc reservations do not require a transaction, - * we can go on without dropping the lock here. + * we can go on without dropping the lock here. If we + * are allocating a new delalloc block, make sure that + * we set the new flag so that we mark the buffer new so + * that we know that it is newly allocated if the write + * fails. */ + if (nimaps && imap.br_startblock == HOLESTARTBLOCK) + new = 1; error = xfs_iomap_write_delay(ip, offset, size, &imap); if (error) goto out_unlock; @@ -1408,52 +1415,91 @@ out_destroy_ioend: return ret; } +/* + * Punch out the delalloc blocks we have already allocated. + * + * Don't bother with xfs_setattr given that nothing can have made it to disk yet + * as the page is still locked at this point. + */ +STATIC void +xfs_vm_kill_delalloc_range( + struct inode *inode, + loff_t start, + loff_t end) +{ + struct xfs_inode *ip = XFS_I(inode); + xfs_fileoff_t start_fsb; + xfs_fileoff_t end_fsb; + int error; + + start_fsb = XFS_B_TO_FSB(ip->i_mount, start); + end_fsb = XFS_B_TO_FSB(ip->i_mount, end); + if (end_fsb <= start_fsb) + return; + + xfs_ilock(ip, XFS_ILOCK_EXCL); + error = xfs_bmap_punch_delalloc_range(ip, start_fsb, + end_fsb - start_fsb); + if (error) { + /* something screwed, just bail */ + if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) { + xfs_alert(ip->i_mount, + "xfs_vm_write_failed: unable to clean up ino %lld", + ip->i_ino); + } + } + xfs_iunlock(ip, XFS_ILOCK_EXCL); +} + STATIC void xfs_vm_write_failed( - struct address_space *mapping, - loff_t to) + struct inode *inode, + struct page *page, + loff_t pos, + unsigned len) { - struct inode *inode = mapping->host; + loff_t block_offset = pos & PAGE_MASK; + loff_t block_start; + loff_t block_end; + loff_t from = pos & (PAGE_CACHE_SIZE - 1); + loff_t to = from + len; + struct buffer_head *bh, *head; - if (to > inode->i_size) { - /* - * Punch out the delalloc blocks we have already allocated. - * - * Don't bother with xfs_setattr given that nothing can have - * made it to disk yet as the page is still locked at this - * point. - */ - struct xfs_inode *ip = XFS_I(inode); - xfs_fileoff_t start_fsb; - xfs_fileoff_t end_fsb; - int error; + ASSERT(block_offset + from == pos); - truncate_pagecache(inode, to, inode->i_size); + head = page_buffers(page); + block_start = 0; + for (bh = head; bh != head || !block_start; + bh = bh->b_this_page, block_start = block_end, + block_offset += bh->b_size) { + block_end = block_start + bh->b_size; - /* - * Check if there are any blocks that are outside of i_size - * that need to be trimmed back. - */ - start_fsb = XFS_B_TO_FSB(ip->i_mount, inode->i_size); - end_fsb = XFS_B_TO_FSB(ip->i_mount, to); - if (end_fsb <= start_fsb) - return; - - xfs_ilock(ip, XFS_ILOCK_EXCL); - error = xfs_bmap_punch_delalloc_range(ip, start_fsb, - end_fsb - start_fsb); - if (error) { - /* something screwed, just bail */ - if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) { - xfs_alert(ip->i_mount, - "xfs_vm_write_failed: unable to clean up ino %lld", - ip->i_ino); - } - } - xfs_iunlock(ip, XFS_ILOCK_EXCL); + /* skip buffers before the write */ + if (block_end <= from) + continue; + + /* if the buffer is after the write, we're done */ + if (block_start >= to) + break; + + if (!buffer_delay(bh)) + continue; + + if (!buffer_new(bh) && block_offset < i_size_read(inode)) + continue; + + xfs_vm_kill_delalloc_range(inode, block_offset, + block_offset + bh->b_size); } + } +/* + * This used to call block_write_begin(), but it unlocks and releases the page + * on error, and we need that page to be able to punch stale delalloc blocks out + * on failure. hence we copy-n-waste it here and call xfs_vm_write_failed() at + * the appropriate point. + */ STATIC int xfs_vm_write_begin( struct file *file, @@ -1464,15 +1510,40 @@ xfs_vm_write_begin( struct page **pagep, void **fsdata) { - int ret; + pgoff_t index = pos >> PAGE_CACHE_SHIFT; + struct page *page; + int status; - ret = block_write_begin(mapping, pos, len, flags | AOP_FLAG_NOFS, - pagep, xfs_get_blocks); - if (unlikely(ret)) - xfs_vm_write_failed(mapping, pos + len); - return ret; + ASSERT(len <= PAGE_CACHE_SIZE); + + page = grab_cache_page_write_begin(mapping, index, + flags | AOP_FLAG_NOFS); + if (!page) + return -ENOMEM; + + status = __block_write_begin(page, pos, len, xfs_get_blocks); + if (unlikely(status)) { + struct inode *inode = mapping->host; + + xfs_vm_write_failed(inode, page, pos, len); + unlock_page(page); + + if (pos + len > i_size_read(inode)) + truncate_pagecache(inode, pos + len, i_size_read(inode)); + + page_cache_release(page); + page = NULL; + } + + *pagep = page; + return status; } +/* + * On failure, we only need to kill delalloc blocks beyond EOF because they + * will never be written. For blocks within EOF, generic_write_end() zeros them + * so they are safe to leave alone and be written with all the other valid data. + */ STATIC int xfs_vm_write_end( struct file *file, @@ -1485,9 +1556,19 @@ xfs_vm_write_end( { int ret; + ASSERT(len <= PAGE_CACHE_SIZE); + ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata); - if (unlikely(ret < len)) - xfs_vm_write_failed(mapping, pos + len); + if (unlikely(ret < len)) { + struct inode *inode = mapping->host; + size_t isize = i_size_read(inode); + loff_t to = pos + len; + + if (to > isize) { + truncate_pagecache(inode, to, isize); + xfs_vm_kill_delalloc_range(inode, isize, to); + } + } return ret; } |
