2020-05-20 02:46:49

by Zheng Bin

[permalink] [raw]
Subject: [PATCH v2] nfs: set invalid blocks after NFSv4 writes

Use the following command to test nfsv4(size of file1M is 1MB):
mount -t nfs -o vers=4.0,actimeo=60 127.0.0.1/dir1 /mnt
cp file1M /mnt
du -h /mnt/file1M -->0 within 60s, then 1M

When write is done(cp file1M /mnt), will call this:
nfs_writeback_done
nfs4_write_done
nfs4_write_done_cb
nfs_writeback_update_inode
nfs_post_op_update_inode_force_wcc_locked(change, ctime, mtime
nfs_post_op_update_inode_force_wcc_locked
nfs_set_cache_invalid
nfs_refresh_inode_locked
nfs_update_inode

nfsd write response contains change, ctime, mtime, the flag will be
clear after nfs_update_inode. Howerver, write response does not contain
space_used, previous open response contains space_used whose value is 0,
so inode->i_blocks is still 0.

nfs_getattr -->called by "du -h"
do_update |= force_sync || nfs_attribute_cache_expired -->false in 60s
cache_validity = READ_ONCE(NFS_I(inode)->cache_validity)
do_update |= cache_validity & (NFS_INO_INVALID_ATTR -->false
if (do_update) {
__nfs_revalidate_inode
}

Within 60s, does not send getattr request to nfsd, thus "du -h /mnt/file1M"
is 0.

Add a NFS_INO_INVALID_BLOCKS flag, set it when nfsv4 write is done.

Fixes: 16e143751727 ("NFS: More fine grained attribute tracking")
Signed-off-by: Zheng Bin <[email protected]>
---

v1->v2: add STATX_BLOCKS check in nfs_getattr

fs/nfs/inode.c | 11 +++++++++--
include/linux/nfs_fs.h | 1 +
2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index b9d0921cb4fe..0a89130a66c0 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -833,6 +833,8 @@ int nfs_getattr(const struct path *path, struct kstat *stat,
do_update |= cache_validity & NFS_INO_INVALID_ATIME;
if (request_mask & (STATX_CTIME|STATX_MTIME))
do_update |= cache_validity & NFS_INO_REVAL_PAGECACHE;
+ if (request_mask & STATX_BLOCKS)
+ do_update |= cache_validity & NFS_INO_INVALID_BLOCKS;
if (do_update) {
/* Update the attribute cache */
if (!(server->flags & NFS_MOUNT_NOAC))
@@ -1764,7 +1766,8 @@ int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fa
status = nfs_post_op_update_inode_locked(inode, fattr,
NFS_INO_INVALID_CHANGE
| NFS_INO_INVALID_CTIME
- | NFS_INO_INVALID_MTIME);
+ | NFS_INO_INVALID_MTIME
+ | NFS_INO_INVALID_BLOCKS);
return status;
}

@@ -2033,8 +2036,12 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
} else if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
inode->i_blocks = fattr->du.nfs2.blocks;
- else
+ else {
+ nfsi->cache_validity |= save_cache_validity &
+ (NFS_INO_INVALID_BLOCKS
+ | NFS_INO_REVAL_FORCED);
cache_revalidated = false;
+ }

/* Update attrtimeo value if we're out of the unstable period */
if (attr_changed) {
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 73eda45f1cfd..6ee9119acc5d 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -230,6 +230,7 @@ struct nfs4_copy_state {
#define NFS_INO_INVALID_OTHER BIT(12) /* other attrs are invalid */
#define NFS_INO_DATA_INVAL_DEFER \
BIT(13) /* Deferred cache invalidation */
+#define NFS_INO_INVALID_BLOCKS BIT(14) /* cached blocks are invalid */

#define NFS_INO_INVALID_ATTR (NFS_INO_INVALID_CHANGE \
| NFS_INO_INVALID_CTIME \
--
2.26.0.106.g9fadedd