From 54566b2c1594c2326a645a3551f9d989f7ba3c5e Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Sun, 4 Jan 2009 12:00:53 -0800 Subject: fs: symlink write_begin allocation context fix With the write_begin/write_end aops, page_symlink was broken because it could no longer pass a GFP_NOFS type mask into the point where the allocations happened. They are done in write_begin, which would always assume that the filesystem can be entered from reclaim. This bug could cause filesystem deadlocks. The funny thing with having a gfp_t mask there is that it doesn't really allow the caller to arbitrarily tinker with the context in which it can be called. It couldn't ever be GFP_ATOMIC, for example, because it needs to take the page lock. The only thing any callers care about is __GFP_FS anyway, so turn that into a single flag. Add a new flag for write_begin, AOP_FLAG_NOFS. Filesystems can now act on this flag in their write_begin function. Change __grab_cache_page to accept a nofs argument as well, to honour that flag (while we're there, change the name to grab_cache_page_write_begin which is more instructive and does away with random leading underscores). This is really a more flexible way to go in the end anyway -- if a filesystem happens to want any extra allocations aside from the pagecache ones in ints write_begin function, it may now use GFP_KERNEL (rather than GFP_NOFS) for common case allocations (eg. ocfs2_alloc_write_ctxt, for a random example). [kosaki.motohiro@jp.fujitsu.com: fix ubifs] [kosaki.motohiro@jp.fujitsu.com: fix fuse] Signed-off-by: Nick Piggin Reviewed-by: KOSAKI Motohiro Cc: [2.6.28.x] Signed-off-by: KOSAKI Motohiro Signed-off-by: Andrew Morton [ Cleaned up the calling convention: just pass in the AOP flags untouched to the grab_cache_page_write_begin() function. That just simplifies everybody, and may even allow future expansion of the logic. - Linus ] Signed-off-by: Linus Torvalds --- fs/reiserfs/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/reiserfs/inode.c') diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c index 145c2d3e5e0..ed04f47007f 100644 --- a/fs/reiserfs/inode.c +++ b/fs/reiserfs/inode.c @@ -2561,7 +2561,7 @@ static int reiserfs_write_begin(struct file *file, } index = pos >> PAGE_CACHE_SHIFT; - page = __grab_cache_page(mapping, index); + page = grab_cache_page_write_begin(mapping, index, flags); if (!page) return -ENOMEM; *pagep = page; -- cgit v1.2.3-70-g09d2 From 2f1169e2dc0c70e213f79ada88a10912cc2fbe94 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 2 Jan 2009 08:16:51 -0500 Subject: fix breakage in reiserfs_new_inode() now that we use ih.key earlier, we need to do all its setup early enough Signed-off-by: Al Viro --- fs/reiserfs/inode.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) (limited to 'fs/reiserfs/inode.c') diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c index 145c2d3e5e0..1306d4f0f44 100644 --- a/fs/reiserfs/inode.c +++ b/fs/reiserfs/inode.c @@ -1782,6 +1782,12 @@ int reiserfs_new_inode(struct reiserfs_transaction_handle *th, goto out_bad_inode; } args.objectid = inode->i_ino = le32_to_cpu(ih.ih_key.k_objectid); + if (old_format_only(sb)) + make_le_item_head(&ih, NULL, KEY_FORMAT_3_5, SD_OFFSET, + TYPE_STAT_DATA, SD_V1_SIZE, MAX_US_INT); + else + make_le_item_head(&ih, NULL, KEY_FORMAT_3_6, SD_OFFSET, + TYPE_STAT_DATA, SD_SIZE, MAX_US_INT); memcpy(INODE_PKEY(inode), &(ih.ih_key), KEY_SIZE); args.dirid = le32_to_cpu(ih.ih_key.k_dir_id); if (insert_inode_locked4(inode, args.objectid, @@ -1834,13 +1840,6 @@ int reiserfs_new_inode(struct reiserfs_transaction_handle *th, reiserfs_init_acl_default(inode); reiserfs_init_xattr_rwsem(inode); - if (old_format_only(sb)) - make_le_item_head(&ih, NULL, KEY_FORMAT_3_5, SD_OFFSET, - TYPE_STAT_DATA, SD_V1_SIZE, MAX_US_INT); - else - make_le_item_head(&ih, NULL, KEY_FORMAT_3_6, SD_OFFSET, - TYPE_STAT_DATA, SD_SIZE, MAX_US_INT); - /* key to search for correct place for new stat data */ _make_cpu_key(&key, KEY_FORMAT_3_6, le32_to_cpu(ih.ih_key.k_dir_id), le32_to_cpu(ih.ih_key.k_objectid), SD_OFFSET, -- cgit v1.2.3-70-g09d2