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; 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); struct nfs_inode *nfsi = NFS_I(inode);
unsigned long ret = 0;
if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE) if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
&& (fattr->valid & NFS_ATTR_FATTR_CHANGE) && (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; nfsi->change_attr = fattr->change_attr;
if (S_ISDIR(inode->i_mode)) if (S_ISDIR(inode->i_mode))
nfsi->cache_validity |= NFS_INO_INVALID_DATA; nfsi->cache_validity |= NFS_INO_INVALID_DATA;
ret |= NFS_INO_INVALID_ATTR;
} }
/* If we have atomic WCC data, we may update some attributes */ /* If we have atomic WCC data, we may update some attributes */
if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME) if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
&& (fattr->valid & NFS_ATTR_FATTR_CTIME) && (fattr->valid & NFS_ATTR_FATTR_CTIME)
&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) && timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime)); memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
ret |= NFS_INO_INVALID_ATTR;
}
if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME) if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
&& (fattr->valid & NFS_ATTR_FATTR_MTIME) && (fattr->valid & NFS_ATTR_FATTR_MTIME)
&& timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) { && timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime)); memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
if (S_ISDIR(inode->i_mode)) if (S_ISDIR(inode->i_mode))
nfsi->cache_validity |= NFS_INO_INVALID_DATA; nfsi->cache_validity |= NFS_INO_INVALID_DATA;
ret |= NFS_INO_INVALID_ATTR;
} }
if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE) if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
&& (fattr->valid & NFS_ATTR_FATTR_SIZE) && (fattr->valid & NFS_ATTR_FATTR_SIZE)
&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size) && i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
&& nfsi->npages == 0) && nfsi->npages == 0) {
i_size_write(inode, nfs_size_to_loff_t(fattr->size)); 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); | NFS_INO_REVAL_PAGECACHE);
/* Do atomic weak cache consistency updates */ /* Do atomic weak cache consistency updates */
nfs_wcc_update_inode(inode, fattr); invalid |= nfs_wcc_update_inode(inode, fattr);
/* More cache consistency checks */ /* More cache consistency checks */
if (fattr->valid & NFS_ATTR_FATTR_CHANGE) { if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {