kernel.git/fs/ecryptfs/mmap.c, branch linux-2.6.28.y

fs: symlink write_begin allocation context fix

2009-01-18T18:43:46Z

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 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

ecryptfs: convert to use new aops

2008-10-16T18:21:39Z

Convert ecryptfs to use write_begin/write_end Signed-off-by: Nick Piggin Signed-off-by: Badari Pulavarty Acked-by: Michael Halcrow Cc: Dave Kleikamp Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ecryptfs: inode.c mmap.c use unaligned byteorder helpers

2008-07-24T17:47:31Z

Fixe sparse warnings: fs/ecryptfs/inode.c:368:15: warning: cast to restricted __be64 fs/ecryptfs/mmap.c:385:12: warning: incorrect type in assignment (different base types) fs/ecryptfs/mmap.c:385:12: expected unsigned long long [unsigned] [assigned] [usertype] file_size fs/ecryptfs/mmap.c:385:12: got restricted __be64 [usertype] fs/ecryptfs/mmap.c:428:12: warning: incorrect type in assignment (different base types) fs/ecryptfs/mmap.c:428:12: expected unsigned long long [unsigned] [assigned] [usertype] file_size fs/ecryptfs/mmap.c:428:12: got restricted __be64 [usertype] Signed-off-by: Harvey Harrison Cc: Michael Halcrow Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ecryptfs: replace remaining FUNCTION occurrences

2008-04-29T15:06:06Z

__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison Cc: Michael Halcrow Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

eCryptfs: make ecryptfs_prepare_write decrypt the page

2008-03-05T00:35:16Z

When the page is not up to date, ecryptfs_prepare_write() should be acting much like ecryptfs_readpage(). This includes the painfully obvious step of actually decrypting the page contents read from the lower encrypted file. Note that this patch resolves a bug in eCryptfs in 2.6.24 that one can produce with these steps: # mount -t ecryptfs /secret /secret # echo "abc" > /secret/file.txt # umount /secret # mount -t ecryptfs /secret /secret # echo "def" >> /secret/file.txt # cat /secret/file.txt Without this patch, the resulting data returned from cat is likely to be something other than "abc\ndef\n". (Thanks to Benedikt Driessen for reporting this.) Signed-off-by: Michael Halcrow Cc: Benedikt Driessen Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

eCryptfs: track header bytes rather than extents

2008-02-06T18:41:12Z

Remove internal references to header extents; just keep track of header bytes instead. Headers can easily span multiple pages with the recent persistent file changes. Signed-off-by: Michael Halcrow Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fs/ecryptfs/: possible cleanups

2008-02-06T18:41:12Z

- make the following needlessly global code static: - crypto.c:ecryptfs_lower_offset_for_extent() - crypto.c:key_tfm_list - crypto.c:key_tfm_list_mutex - inode.c:ecryptfs_getxattr() - main.c:ecryptfs_init_persistent_file() - remove the no longer used mmap.c:ecryptfs_lower_page_cache - #if 0 the unused read_write.c:ecryptfs_read() Signed-off-by: Adrian Bunk Cc: Michael Halcrow Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Pagecache zeroing: zero_user_segment, zero_user_segments and zero_user

2008-02-05T17:44:13Z

Simplify page cache zeroing of segments of pages through 3 functions zero_user_segments(page, start1, end1, start2, end2) Zeros two segments of the page. It takes the position where to start and end the zeroing which avoids length calculations and makes code clearer. zero_user_segment(page, start, end) Same for a single segment. zero_user(page, start, length) Length variant for the case where we know the length. We remove the zero_user_page macro. Issues: 1. Its a macro. Inline functions are preferable. 2. The KM_USER0 macro is only defined for HIGHMEM. Having to treat this special case everywhere makes the code needlessly complex. The parameter for zeroing is always KM_USER0 except in one single case that we open code. Avoiding KM_USER0 makes a lot of code not having to be dealing with the special casing for HIGHMEM anymore. Dealing with kmap is only necessary for HIGHMEM configurations. In those configurations we use KM_USER0 like we do for a series of other functions defined in highmem.h. Since KM_USER0 is depends on HIGHMEM the existing zero_user_page function could not be a macro. zero_user_* functions introduced here can be be inline because that constant is not used when these functions are called. Also extract the flushing of the caches to be outside of the kmap. [akpm@linux-foundation.org: fix nfs and ntfs build] [akpm@linux-foundation.org: fix ntfs build some more] Signed-off-by: Christoph Lameter Cc: Steven French Cc: Michael Halcrow Cc: Cc: Steven Whitehouse Cc: Trond Myklebust Cc: "J. Bruce Fields" Cc: Anton Altaparmakov Cc: Mark Fasheh Cc: David Chinner Cc: Michael Halcrow Cc: Steven French Cc: Steven Whitehouse Cc: Trond Myklebust Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ecryptfs: fix fsx data corruption problems

2007-12-18T03:28:17Z

ecryptfs in 2.6.24-rc3 wasn't surviving fsx for me at all, dying after 4 ops. Generally, encountering problems with stale data and improperly zeroed pages. An extending truncate + write for example would expose stale data. With the changes below I got to a million ops and beyond with all mmap ops disabled - mmap still needs work. (A version of this patch on a RHEL5 kernel ran for over 110 million fsx ops) I added a few comments as well, to the best of my understanding as I read through the code. Signed-off-by: Eric Sandeen Acked-by: Michael Halcrow Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ecryptfs: clean up page flag handling

2007-10-16T16:43:12Z

The functions that eventually call down to ecryptfs_read_lower(), ecryptfs_decrypt_page(), and ecryptfs_copy_up_encrypted_with_header() should have the responsibility of managing the page Uptodate status. This patch gets rid of some of the ugliness that resulted from trying to push some of the page flag setting too far down the stack. Signed-off-by: Michael Halcrow Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds