tree a72825f122c9e38d4adc42ebcfd127f366da4a0f
parent f33321141b273d60cbb3a8f56a5489baad82ba5e
author Miklos Szeredi <mszeredi@suse.cz> 1192702025 -0700
committer Linus Torvalds <torvalds@woody.linux-foundation.org> 1192743451 -0700

fuse: add blksize field to fuse_attr

There are cases when the filesystem will be passed the buffer from a single
read or write call, namely:

 1) in 'direct-io' mode (not O_DIRECT), read/write requests don't go
    through the page cache, but go directly to the userspace fs

 2) currently buffered writes are done with single page requests, but
    if Nick's ->perform_write() patch goes it, it will be possible to
    do larger write requests.  But only if the original write() was
    also bigger than a page.

In these cases the filesystem might want to give a hint to the app
about the optimal I/O size.

Allow the userspace filesystem to supply a blksize value to be returned by
stat() and friends.  If the field is zero, it defaults to the old
PAGE_CACHE_SIZE value.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>