diff options
author | Frank van der Linden <fllinden@amazon.com> | 2020-06-23 22:39:04 +0000 |
---|---|---|
committer | Trond Myklebust <trond.myklebust@hammerspace.com> | 2020-07-13 17:52:46 -0400 |
commit | 95ad37f90c338e3fd4abf61cecfe02b6f3e080f0 (patch) | |
tree | cc65ec6496ed30eb9a48cf2eeda6e19be734c65f /fs/nfs/nfs42proc.c | |
parent | 012a211abd5db098094ce429de5f046368391e68 (diff) |
NFSv4.2: add client side xattr caching.
Implement client side caching for NFSv4.2 extended attributes. The cache
is a per-inode hashtable, with name/value entries. There is one special
entry for the listxattr cache.
NFS inodes have a pointer to a cache structure. The cache structure is
allocated on demand, freed when the cache is invalidated.
Memory shrinkers keep the size in check. Large entries (> PAGE_SIZE)
are collected by a separate shrinker, and freed more aggressively
than others.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Diffstat (limited to 'fs/nfs/nfs42proc.c')
-rw-r--r-- | fs/nfs/nfs42proc.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c index 8c2e52bc986a..e200522469af 100644 --- a/fs/nfs/nfs42proc.c +++ b/fs/nfs/nfs42proc.c @@ -1182,6 +1182,18 @@ static ssize_t _nfs42_proc_getxattr(struct inode *inode, const char *name, if (ret < 0) return ret; + /* + * Normally, the caching is done one layer up, but for successful + * RPCS, always cache the result here, even if the caller was + * just querying the length, or if the reply was too big for + * the caller. This avoids a second RPC in the case of the + * common query-alloc-retrieve cycle for xattrs. + * + * Note that xattr_len is always capped to XATTR_SIZE_MAX. + */ + + nfs4_xattr_cache_add(inode, name, NULL, pages, res.xattr_len); + if (buflen) { if (res.xattr_len > buflen) return -ERANGE; |