kernel.git/fs/nfs/dir.c, branch linux-5.19.y

NFSv4: Add FMODE_CAN_ODIRECT after successful open of a NFS4.x file

2022-06-15T19:03:12Z

Commit a2ad63daa88b ("VFS: add FMODE_CAN_ODIRECT file flag") added the FMODE_CAN_ODIRECT flag for NFSv3 but neglected to add it for NFSv4.x. This causes direct io on NFSv4.x to fail open with EINVAL: mount -o vers=4.2 127.0.0.1:/export /mnt/nfs4 dd if=/dev/zero of=/mnt/nfs4/file.bin bs=128k count=1 oflag=direct dd: failed to open '/mnt/nfs4/file.bin': Invalid argument dd of=/dev/null if=/mnt/nfs4/file.bin bs=128k count=1 iflag=direct dd: failed to open '/mnt/dir1/file1.bin': Invalid argument Fixes: a2ad63daa88b ("VFS: add FMODE_CAN_ODIRECT file flag") Signed-off-by: Dave Wysochanski Signed-off-by: Anna Schumaker

nfs: Convert to free_folio

2022-05-10T03:12:53Z

Add a wrapper that converts back from the folio to the page. This entire file needs to be converted to use folios, but that's a task for a different set of patches. Signed-off-by: Matthew Wilcox (Oracle)

NFS: Replace readdir's use of xxhash() with hash_64()

2022-04-07T20:19:47Z

Both xxhash() and hash_64() appear to give similarly low collision rates with a standard linearly increasing readdir offset. They both give similarly higher collision rates when applied to ext4's offsets. So switch to using the standard hash_64(). Signed-off-by: Trond Myklebust

NFSv4: fix open failure with O_ACCMODE flag

2022-03-30T02:14:00Z

open() with O_ACCMODE|O_DIRECT flags secondly will fail. Reproducer: 1. mount -t nfs -o vers=4.2 $server_ip:/ /mnt/ 2. fd = open("/mnt/file", O_ACCMODE|O_DIRECT|O_CREAT) 3. close(fd) 4. fd = open("/mnt/file", O_ACCMODE|O_DIRECT) Server nfsd4_decode_share_access() will fail with error nfserr_bad_xdr when client use incorrect share access mode of 0. Fix this by using NFS4_SHARE_ACCESS_BOTH share access mode in client, just like firstly opening. Fixes: ce4ef7c0a8a05 ("NFS: Split out NFS v4 file operations") Signed-off-by: ChenXiaoSong Signed-off-by: Trond Myklebust

NFS: Fix revalidation of empty readdir pages

2022-03-22T19:52:55Z

If the page is empty, we need to check the array->last_cookie instead of the first entry. Add a helper for the cases where we care. Signed-off-by: Trond Myklebust

NFS: Don't deadlock when cookie hashes collide

2022-03-22T13:14:39Z

In the very rare case where the readdir reply contains multiple cookies that map to the same hash value, we can end up deadlocking waiting for a page lock that we already hold. In this case we should fail the page lock by using grab_cache_page_nowait(). Signed-off-by: Trond Myklebust

NFS: Cache all entries in the readdirplus reply

2022-03-02T13:43:39Z

Even if we're not able to cache all the entries in the readdir buffer, let's ensure that we do prime the dcache. Signed-off-by: Trond Myklebust

NFS: Optimise away the previous cookie field

2022-03-02T13:43:39Z

Replace the 'previous cookie' field in struct nfs_entry with the array->last_cookie. Signed-off-by: Trond Myklebust

NFS: Fix up forced readdirplus

2022-03-02T13:43:39Z

Avoid clearing the entire readdir page cache if we're just doing forced readdirplus for the 'ls -l' heuristic. Signed-off-by: Trond Myklebust

NFS: Convert readdir page cache to use a cookie based index

2022-03-02T13:43:39Z

Instead of using a linear index to address the pages, use the cookie of the first entry, since that is what we use to match the page anyway. This allows us to avoid re-reading the entire cache on a seekdir() type of operation. The latter is very common when re-exporting NFS, and is a major performance drain. The change does affect our duplicate cookie detection, since we can no longer rely on the page index as a linear offset for detecting whether we looped backwards. However since we no longer do a linear search through all the pages on each call to nfs_readdir(), this is less of a concern than it was previously. The other downside is that invalidate_mapping_pages() no longer can use the page index to avoid clearing pages that have been read. A subsequent patch will restore the functionality this provides to the 'ls -l' heuristic. Signed-off-by: Trond Myklebust