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54566b2c15
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 <npiggin@suse.de> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: <stable@kernel.org> [2.6.28.x] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> [ 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 <torvalds@linux-foundation.org> |
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.. | ||
locking/dlm | ||
acl.c | ||
acl.h | ||
bmap.c | ||
bmap.h | ||
daemon.c | ||
daemon.h | ||
dir.c | ||
dir.h | ||
eaops.c | ||
eaops.h | ||
eattr.c | ||
eattr.h | ||
gfs2.h | ||
glock.c | ||
glock.h | ||
glops.c | ||
glops.h | ||
incore.h | ||
inode.c | ||
inode.h | ||
Kconfig | ||
locking.c | ||
log.c | ||
log.h | ||
lops.c | ||
lops.h | ||
main.c | ||
Makefile | ||
meta_io.c | ||
meta_io.h | ||
mount.c | ||
mount.h | ||
ops_address.c | ||
ops_address.h | ||
ops_dentry.c | ||
ops_dentry.h | ||
ops_export.c | ||
ops_file.c | ||
ops_fstype.c | ||
ops_fstype.h | ||
ops_inode.c | ||
ops_inode.h | ||
ops_super.c | ||
ops_super.h | ||
quota.c | ||
quota.h | ||
recovery.c | ||
recovery.h | ||
rgrp.c | ||
rgrp.h | ||
super.c | ||
super.h | ||
sys.c | ||
sys.h | ||
trans.c | ||
trans.h | ||
util.c | ||
util.h |