From 4273b793ec68753cc3fcf5be7cbfd88c2be2058d Mon Sep 17 00:00:00 2001 From: Anand Avati Date: Fri, 17 Feb 2012 12:46:25 -0500 Subject: fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati Reviewed-by: Jeff Moyer Signed-off-by: Miklos Szeredi --- fs/fuse/dir.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'fs/fuse/dir.c') diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index da379070fab..df5ac048dc7 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -387,9 +387,6 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, if (fc->no_create) return -ENOSYS; - if (flags & O_DIRECT) - return -EINVAL; - forget = fuse_alloc_forget(); if (!forget) return -ENOMEM; -- cgit v1.2.3-70-g09d2