5.10-stable review patch. If anyone has any objections, please let me know.
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From: J. Bruce Fields bfields@redhat.com
[ Upstream commit 3cc55f4434b421d37300aa9a167ace7d60b45ccf ]
When exporting NFS, we may as well use the real change attribute returned by the original server instead of faking up a change attribute from the ctime.
Note we can't do that by setting I_VERSION--that would also turn on the logic in iversion.h which treats the lower bit specially, and that doesn't make sense for NFS.
So instead we define a new export operation for filesystems like NFS that want to manage the change attribute themselves.
Signed-off-by: J. Bruce Fields bfields@redhat.com Reviewed-by: Christoph Hellwig hch@lst.de Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfs/export.c | 18 ++++++++++++++++++ fs/nfsd/nfsfh.h | 5 ++++- include/linux/exportfs.h | 1 + 3 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/fs/nfs/export.c b/fs/nfs/export.c index 7412bb164fa77..f2b34cfe286c2 100644 --- a/fs/nfs/export.c +++ b/fs/nfs/export.c @@ -167,10 +167,28 @@ nfs_get_parent(struct dentry *dentry) return parent; }
+static u64 nfs_fetch_iversion(struct inode *inode) +{ + struct nfs_server *server = NFS_SERVER(inode); + + /* Is this the right call?: */ + nfs_revalidate_inode(server, inode); + /* + * Also, note we're ignoring any returned error. That seems to be + * the practice for cache consistency information elsewhere in + * the server, but I'm not sure why. + */ + if (server->nfs_client->rpc_ops->version >= 4) + return inode_peek_iversion_raw(inode); + else + return time_to_chattr(&inode->i_ctime); +} + const struct export_operations nfs_export_ops = { .encode_fh = nfs_encode_fh, .fh_to_dentry = nfs_fh_to_dentry, .get_parent = nfs_get_parent, + .fetch_iversion = nfs_fetch_iversion, .flags = EXPORT_OP_NOWCC|EXPORT_OP_NOSUBTREECHK| EXPORT_OP_CLOSE_BEFORE_UNLINK|EXPORT_OP_REMOTE_FS| EXPORT_OP_NOATOMIC_ATTR, diff --git a/fs/nfsd/nfsfh.h b/fs/nfsd/nfsfh.h index cb20c2cd34695..f58933519f380 100644 --- a/fs/nfsd/nfsfh.h +++ b/fs/nfsd/nfsfh.h @@ -12,6 +12,7 @@ #include <linux/sunrpc/svc.h> #include <uapi/linux/nfsd/nfsfh.h> #include <linux/iversion.h> +#include <linux/exportfs.h>
static inline __u32 ino_t_to_u32(ino_t ino) { @@ -264,7 +265,9 @@ fh_clear_wcc(struct svc_fh *fhp) static inline u64 nfsd4_change_attribute(struct kstat *stat, struct inode *inode) { - if (IS_I_VERSION(inode)) { + if (inode->i_sb->s_export_op->fetch_iversion) + return inode->i_sb->s_export_op->fetch_iversion(inode); + else if (IS_I_VERSION(inode)) { u64 chattr;
chattr = stat->ctime.tv_sec; diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h index 9f4d4bcbf251d..fe848901fcc3a 100644 --- a/include/linux/exportfs.h +++ b/include/linux/exportfs.h @@ -213,6 +213,7 @@ struct export_operations { bool write, u32 *device_generation); int (*commit_blocks)(struct inode *inode, struct iomap *iomaps, int nr_iomaps, struct iattr *iattr); + u64 (*fetch_iversion)(struct inode *); #define EXPORT_OP_NOWCC (0x1) /* don't collect v3 wcc data */ #define EXPORT_OP_NOSUBTREECHK (0x2) /* no subtree checking */ #define EXPORT_OP_CLOSE_BEFORE_UNLINK (0x4) /* close files before unlink */