NFS: nfs_wcc_update_inode() should set nfsi->attr_gencount

If the call to nfs_wcc_update_inode() results in an attribute update, we
need to ensure that the inode's attr_gencount gets bumped too, otherwise
we are not protected against races with other GETATTR calls.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2011-01-25 15:28:21 -05:00
parent b2a2897dc4
commit 27dc1cd3ad

View File

@ -881,9 +881,10 @@ out:
return ret;
}
static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
static unsigned long nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
{
struct nfs_inode *nfsi = NFS_I(inode);
unsigned long ret = 0;
if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
@ -891,25 +892,32 @@ static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
nfsi->change_attr = fattr->change_attr;
if (S_ISDIR(inode->i_mode))
nfsi->cache_validity |= NFS_INO_INVALID_DATA;
ret |= NFS_INO_INVALID_ATTR;
}
/* If we have atomic WCC data, we may update some attributes */
if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime))
memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
ret |= NFS_INO_INVALID_ATTR;
}
if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
&& timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
if (S_ISDIR(inode->i_mode))
nfsi->cache_validity |= NFS_INO_INVALID_DATA;
memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
if (S_ISDIR(inode->i_mode))
nfsi->cache_validity |= NFS_INO_INVALID_DATA;
ret |= NFS_INO_INVALID_ATTR;
}
if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
&& nfsi->npages == 0)
i_size_write(inode, nfs_size_to_loff_t(fattr->size));
&& nfsi->npages == 0) {
i_size_write(inode, nfs_size_to_loff_t(fattr->size));
ret |= NFS_INO_INVALID_ATTR;
}
return ret;
}
/**
@ -1223,7 +1231,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
| NFS_INO_REVAL_PAGECACHE);
/* Do atomic weak cache consistency updates */
nfs_wcc_update_inode(inode, fattr);
invalid |= nfs_wcc_update_inode(inode, fattr);
/* More cache consistency checks */
if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {