linux/fs, branch v2.6.27.12

nfs: remove redundant tests on reading new pages

2009-01-18T18:35:44Z

commit 136221fc3219b3805c48db5da065e8e3467175d4 upstream. aops->readpages() and its NFS helper readpage_async_filler() will only be called to do readahead I/O for newly allocated pages. So it's not necessary to test for the always 0 dirty/uptodate page flags. The removal of nfs_wb_page() call also fixes a readahead bug: the NFS readahead has been synchronous since 2.6.23, because that call will clear PG_readahead, which is the reminder for asynchronous readahead. More background: the PG_readahead page flag is shared with PG_reclaim, one for read path and the other for write path. clear_page_dirty_for_io() unconditionally clears PG_readahead to prevent possible readahead residuals, assuming itself to be always called in the write path. However, NFS is one and the only exception in that it _always_ calls clear_page_dirty_for_io() in the read path, i.e. for readpages()/readpage(). Cc: Trond Myklebust Signed-off-by: Wu Fengguang Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman

fs: symlink write_begin allocation context fix

2009-01-18T18:35:43Z

commit 54566b2c1594c2326a645a3551f9d989f7ba3c5e upstream. 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: 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 Signed-off-by: Greg Kroah-Hartman

fix switch_names() breakage in short-to-short case

2009-01-18T18:35:41Z

commit dc711ca35f9d95a1eec02118e0c298b5e3068315 upstream. We want ->name.len to match the resulting name on *both* source and target Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

eCryptfs: check readlink result was not an error before using it

2009-01-18T18:35:40Z

commit a17d5232de7b53d34229de79ec22f4bb04adb7e4 upstream. The result from readlink is being used to index into the link name buffer without checking whether it is a valid length. If readlink returns an error this will fault or cause memory corruption. Cc: Tyler Hicks Cc: Dustin Kirkland Cc: ecryptfs-devel@lists.launchpad.net Signed-off-by: Duane Griffin Acked-by: Michael Halcrow Acked-by: Tyler Hicks Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

System call wrappers part 33

2009-01-18T18:35:40Z

commit 2b66421995d2e93c9d1a0111acf2581f8529c6e5 upstream. Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

System call wrappers part 32

2009-01-18T18:35:40Z

commit d4e82042c4cfa87a7d51710b71f568fe80132551 upstream. Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

System call wrappers part 31

2009-01-18T18:35:40Z

commit 836f92adf121f806e9beb5b6b88bd5c9c4ea3f24 upstream. Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

System call wrappers part 30

2009-01-18T18:35:39Z

commit 6559eed8ca7db0531a207cd80be5e28cd6f213c5 upstream. Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

System call wrappers part 29

2009-01-18T18:35:39Z

commit 2e4d0924eb0c403ce4014fa139d1d61bf2c44fee upstream. Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

System call wrappers part 28

2009-01-18T18:35:39Z

commit 938bb9f5e840eddbf54e4f62f6c5ba9b3ae12c9d upstream. Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman