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NFS: Fix a few further cache consistency regressions
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 Steve Dickson writes:
 Doing the following:
 1. On server:
 $ mkdir ~/t
 $ echo Hello > ~/t/tmp

 2. On client, wait for a string to appear in this file:
 $ until grep -q foo t/tmp ; do echo -n . ; sleep 1 ; done

 3. On server, create a *new* file with the same name containing that
 string:
 $ mv ~/t/tmp ~/t/tmp.old; echo foo > ~/t/tmp

 will show how the client will never (and I mean never ;-) ) see
 the updated file.

 The problem is that we do not update nfsi->cache_change_attribute when the
 file changes on the server (we only update it when our client makes the
 changes). This again means that functions like nfs_check_verifier() will
 fail to register when the parent directory has changed and should trigger
 a dentry lookup revalidation.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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Trond Myklebust authored and Trond Myklebust committed Dec 3, 2005
1 parent 223db12 commit 24aa1fe
Showing 1 changed file with 20 additions and 34 deletions.
54 changes: 20 additions & 34 deletions fs/nfs/inode.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -54,7 +54,7 @@
#define NFS_MAX_READAHEAD (RPC_DEF_SLOT_TABLE - 1)

static void nfs_invalidate_inode(struct inode *);
static int nfs_update_inode(struct inode *, struct nfs_fattr *, unsigned long);
static int nfs_update_inode(struct inode *, struct nfs_fattr *);

static struct inode *nfs_alloc_inode(struct super_block *sb);
static void nfs_destroy_inode(struct inode *);
Expand Down Expand Up @@ -1080,8 +1080,6 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
int status = -ESTALE;
struct nfs_fattr fattr;
struct nfs_inode *nfsi = NFS_I(inode);
unsigned long verifier;
unsigned long cache_validity;

dfprintk(PAGECACHE, "NFS: revalidating (%s/%Ld)\n",
inode->i_sb->s_id, (long long)NFS_FILEID(inode));
Expand All @@ -1106,8 +1104,6 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
}
}

/* Protect against RPC races by saving the change attribute */
verifier = nfs_save_change_attribute(inode);
status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), &fattr);
if (status != 0) {
dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) getattr failed, error=%d\n",
Expand All @@ -1122,28 +1118,19 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
}

spin_lock(&inode->i_lock);
status = nfs_update_inode(inode, &fattr, verifier);
status = nfs_update_inode(inode, &fattr);
if (status) {
spin_unlock(&inode->i_lock);
dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) refresh failed, error=%d\n",
inode->i_sb->s_id,
(long long)NFS_FILEID(inode), status);
goto out;
}
cache_validity = nfsi->cache_validity;
nfsi->cache_validity &= ~NFS_INO_REVAL_PAGECACHE;

/*
* We may need to keep the attributes marked as invalid if
* we raced with nfs_end_attr_update().
*/
if (time_after_eq(verifier, nfsi->cache_change_attribute))
nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME);
spin_unlock(&inode->i_lock);

nfs_revalidate_mapping(inode, inode->i_mapping);

if (cache_validity & NFS_INO_INVALID_ACL)
if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
nfs_zap_acl_cache(inode);

dfprintk(PAGECACHE, "NFS: (%s/%Ld) revalidation complete\n",
Expand Down Expand Up @@ -1346,10 +1333,8 @@ int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
return 0;
spin_lock(&inode->i_lock);
nfsi->cache_validity &= ~NFS_INO_REVAL_PAGECACHE;
if (nfs_verify_change_attribute(inode, fattr->time_start))
nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME);
if (time_after(fattr->time_start, nfsi->last_updated))
status = nfs_update_inode(inode, fattr, fattr->time_start);
status = nfs_update_inode(inode, fattr);
else
status = nfs_check_inode_attributes(inode, fattr);

Expand All @@ -1375,10 +1360,7 @@ int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
nfsi->cache_validity |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS;
goto out;
}
status = nfs_update_inode(inode, fattr, fattr->time_start);
if (time_after_eq(fattr->time_start, nfsi->cache_change_attribute))
nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME|NFS_INO_REVAL_PAGECACHE);
nfsi->cache_change_attribute = jiffies;
status = nfs_update_inode(inode, fattr);
out:
spin_unlock(&inode->i_lock);
return status;
Expand All @@ -1396,12 +1378,12 @@ int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
*
* A very similar scenario holds for the dir cache.
*/
static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr, unsigned long verifier)
static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
{
struct nfs_inode *nfsi = NFS_I(inode);
loff_t cur_isize, new_isize;
unsigned int invalid = 0;
int data_unstable;
int data_stable;

dfprintk(VFS, "NFS: %s(%s/%ld ct=%d info=0x%x)\n",
__FUNCTION__, inode->i_sb->s_id, inode->i_ino,
Expand Down Expand Up @@ -1432,8 +1414,9 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr, unsign
nfsi->last_updated = jiffies;

/* Are we racing with known updates of the metadata on the server? */
data_unstable = ! (nfs_verify_change_attribute(inode, verifier) ||
(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE));
data_stable = nfs_verify_change_attribute(inode, fattr->time_start);
if (data_stable)
nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME);

/* Check if our cached file size is stale */
new_isize = nfs_size_to_loff_t(fattr->size);
Expand All @@ -1442,7 +1425,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr, unsign
/* Do we perhaps have any outstanding writes? */
if (nfsi->npages == 0) {
/* No, but did we race with nfs_end_data_update()? */
if (time_after_eq(verifier, nfsi->cache_change_attribute)) {
if (data_stable) {
inode->i_size = new_isize;
invalid |= NFS_INO_INVALID_DATA;
}
Expand All @@ -1451,6 +1434,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr, unsign
inode->i_size = new_isize;
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
}
nfsi->cache_change_attribute = jiffies;
dprintk("NFS: isize change on server for file %s/%ld\n",
inode->i_sb->s_id, inode->i_ino);
}
Expand All @@ -1460,24 +1444,24 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr, unsign
memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
dprintk("NFS: mtime change on server for file %s/%ld\n",
inode->i_sb->s_id, inode->i_ino);
if (!data_unstable)
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
nfsi->cache_change_attribute = jiffies;
}

if ((fattr->valid & NFS_ATTR_FATTR_V4)
&& nfsi->change_attr != fattr->change_attr) {
dprintk("NFS: change_attr change on server for file %s/%ld\n",
inode->i_sb->s_id, inode->i_ino);
nfsi->change_attr = fattr->change_attr;
if (!data_unstable)
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
nfsi->cache_change_attribute = jiffies;
}

/* If ctime has changed we should definitely clear access+acl caches */
if (!timespec_equal(&inode->i_ctime, &fattr->ctime)) {
if (!data_unstable)
invalid |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
invalid |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
nfsi->cache_change_attribute = jiffies;
}
memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));

Expand Down Expand Up @@ -1515,6 +1499,8 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr, unsign
if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
|| S_ISLNK(inode->i_mode)))
invalid &= ~NFS_INO_INVALID_DATA;
if (data_stable)
invalid &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME|NFS_INO_REVAL_PAGECACHE);
if (!nfs_have_delegation(inode, FMODE_READ))
nfsi->cache_validity |= invalid;

Expand Down

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