afs: Make it possible to get the data version in readpage

Store the data version number indicated by an FS.FetchData op into the read
request structure so that it's accessible by the page reader.

Signed-off-by: David Howells <dhowells@redhat.com>

5 files changed, 59 insertions, 44 deletions

diff --git a/fs/afs/flock.c b/fs/afs/flock.c
index c40ba2f..7a0e017 100644
--- a/fs/afs/flock.c
+++ b/fs/afs/flock.c
@@ -613,7 +613,7 @@ static int afs_do_getlk(struct file *file, struct file_lock *fl)
 	posix_test_lock(file, fl);
 	if (fl->fl_type == F_UNLCK) {
 		/* no local locks; consult the server */
-		ret = afs_fetch_status(vnode, key);
+		ret = afs_fetch_status(vnode, key, false);
 		if (ret < 0)
 			goto error;
 
diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 90aa3eb..015bbbb 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -69,9 +69,9 @@ static void xdr_dump_bad(const __be32 *bp)
 static void xdr_decode_AFSFetchStatus(const __be32 **_bp,
 				      struct afs_file_status *status,
 				      struct afs_vnode *vnode,
-				      afs_dataversion_t *store_version)
+				      const afs_dataversion_t *expected_version,
+				      afs_dataversion_t *_version)
 {
-	afs_dataversion_t expected_version;
 	const __be32 *bp = *_bp;
 	umode_t mode;
 	u64 data_version, size;
@@ -136,6 +136,8 @@ static void xdr_decode_AFSFetchStatus(const __be32 **_bp,
 		changed |= true;
 	}
 	status->mode &= S_IALLUGO;
+	if (_version)
+		*_version = data_version;
 
 	_debug("vnode time %lx, %lx",
 	       status->mtime_client, status->mtime_server);
@@ -162,12 +164,8 @@ static void xdr_decode_AFSFetchStatus(const __be32 **_bp,
 		inode_set_iversion_raw(&vnode->vfs_inode, data_version);
 	}
 
-	expected_version = status->data_version;
-	if (store_version)
-		expected_version = *store_version;
-
-	if (expected_version != data_version) {
-		status->data_version = data_version;
+	status->data_version = data_version;
+	if (expected_version && *expected_version != data_version) {
 		if (vnode && !test_bit(AFS_VNODE_UNSET, &vnode->flags)) {
 			_debug("vnode modified %llx on {%x:%u}",
 			       (unsigned long long) data_version,
@@ -175,8 +173,6 @@ static void xdr_decode_AFSFetchStatus(const __be32 **_bp,
 			set_bit(AFS_VNODE_DIR_MODIFIED, &vnode->flags);
 			set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
 		}
-	} else if (store_version) {
-		status->data_version = data_version;
 	}
 
 out:
@@ -323,7 +319,8 @@ static int afs_deliver_fs_fetch_status_vnode(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
+	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode,
+				  &call->expected_version, NULL);
 	xdr_decode_AFSCallBack(call, vnode, &bp);
 	if (call->reply[1])
 		xdr_decode_AFSVolSync(&bp, call->reply[1]);
@@ -345,7 +342,8 @@ static const struct afs_call_type afs_RXFSFetchStatus_vnode = {
 /*
  * fetch the status information for a file
  */
-int afs_fs_fetch_file_status(struct afs_fs_cursor *fc, struct afs_volsync *volsync)
+int afs_fs_fetch_file_status(struct afs_fs_cursor *fc, struct afs_volsync *volsync,
+			     bool new_inode)
 {
 	struct afs_vnode *vnode = fc->vnode;
 	struct afs_call *call;
@@ -365,6 +363,7 @@ int afs_fs_fetch_file_status(struct afs_fs_cursor *fc, struct afs_volsync *volsy
 	call->key = fc->key;
 	call->reply[0] = vnode;
 	call->reply[1] = volsync;
+	call->expected_version = new_inode ? 1 : vnode->status.data_version;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -500,7 +499,9 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
 			return ret;
 
 		bp = call->buffer;
-		xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
+		xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode,
+					  &vnode->status.data_version,
+					  &req->new_version);
 		xdr_decode_AFSCallBack(call, vnode, &bp);
 		if (call->reply[1])
 			xdr_decode_AFSVolSync(&bp, call->reply[1]);
@@ -570,6 +571,7 @@ static int afs_fs_fetch_data64(struct afs_fs_cursor *fc, struct afs_read *req)
 	call->reply[0] = vnode;
 	call->reply[1] = NULL; /* volsync */
 	call->reply[2] = req;
+	call->expected_version = vnode->status.data_version;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -614,6 +616,7 @@ int afs_fs_fetch_data(struct afs_fs_cursor *fc, struct afs_read *req)
 	call->reply[0] = vnode;
 	call->reply[1] = NULL; /* volsync */
 	call->reply[2] = req;
+	call->expected_version = vnode->status.data_version;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -649,8 +652,9 @@ static int afs_deliver_fs_create_vnode(struct afs_call *call)
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
 	xdr_decode_AFSFid(&bp, call->reply[1]);
-	xdr_decode_AFSFetchStatus(&bp, call->reply[2], NULL, NULL);
-	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
+	xdr_decode_AFSFetchStatus(&bp, call->reply[2], NULL, NULL, NULL);
+	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode,
+				  &call->expected_version, NULL);
 	xdr_decode_AFSCallBack_raw(&bp, call->reply[3]);
 	/* xdr_decode_AFSVolSync(&bp, call->reply[X]); */
 
@@ -708,6 +712,7 @@ int afs_fs_create(struct afs_fs_cursor *fc,
 	call->reply[1] = newfid;
 	call->reply[2] = newstatus;
 	call->reply[3] = newcb;
+	call->expected_version = vnode->status.data_version;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -751,7 +756,8 @@ static int afs_deliver_fs_remove(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
+	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode,
+				  &call->expected_version, NULL);
 	/* xdr_decode_AFSVolSync(&bp, call->reply[X]); */
 
 	_leave(" = 0 [done]");
@@ -800,6 +806,7 @@ int afs_fs_remove(struct afs_fs_cursor *fc, const char *name, bool isdir)
 
 	call->key = fc->key;
 	call->reply[0] = vnode;
+	call->expected_version = vnode->status.data_version;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -837,8 +844,9 @@ static int afs_deliver_fs_link(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
-	xdr_decode_AFSFetchStatus(&bp, &dvnode->status, dvnode, NULL);
+	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL, NULL);
+	xdr_decode_AFSFetchStatus(&bp, &dvnode->status, dvnode,
+				  &call->expected_version, NULL);
 	/* xdr_decode_AFSVolSync(&bp, call->reply[X]); */
 
 	_leave(" = 0 [done]");
@@ -880,6 +888,7 @@ int afs_fs_link(struct afs_fs_cursor *fc, struct afs_vnode *vnode,
 	call->key = fc->key;
 	call->reply[0] = dvnode;
 	call->reply[1] = vnode;
+	call->expected_version = vnode->status.data_version;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -921,8 +930,9 @@ static int afs_deliver_fs_symlink(struct afs_call *call)
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
 	xdr_decode_AFSFid(&bp, call->reply[1]);
-	xdr_decode_AFSFetchStatus(&bp, call->reply[2], NULL, NULL);
-	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
+	xdr_decode_AFSFetchStatus(&bp, call->reply[2], NULL, NULL, NULL);
+	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode,
+				  &call->expected_version, NULL);
 	/* xdr_decode_AFSVolSync(&bp, call->reply[X]); */
 
 	_leave(" = 0 [done]");
@@ -973,6 +983,7 @@ int afs_fs_symlink(struct afs_fs_cursor *fc,
 	call->reply[0] = vnode;
 	call->reply[1] = newfid;
 	call->reply[2] = newstatus;
+	call->expected_version = vnode->status.data_version;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -1023,10 +1034,11 @@ static int afs_deliver_fs_rename(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	xdr_decode_AFSFetchStatus(&bp, &orig_dvnode->status, orig_dvnode, NULL);
+	xdr_decode_AFSFetchStatus(&bp, &orig_dvnode->status, orig_dvnode,
+				  &call->expected_version, NULL);
 	if (new_dvnode != orig_dvnode)
 		xdr_decode_AFSFetchStatus(&bp, &new_dvnode->status, new_dvnode,
-					  NULL);
+					  &call->expected_version_2, NULL);
 	/* xdr_decode_AFSVolSync(&bp, call->reply[X]); */
 
 	_leave(" = 0 [done]");
@@ -1077,6 +1089,8 @@ int afs_fs_rename(struct afs_fs_cursor *fc,
 	call->key = fc->key;
 	call->reply[0] = orig_dvnode;
 	call->reply[1] = new_dvnode;
+	call->expected_version = orig_dvnode->status.data_version;
+	call->expected_version_2 = new_dvnode->status.data_version;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -1126,7 +1140,7 @@ static int afs_deliver_fs_store_data(struct afs_call *call)
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
 	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode,
-				  &call->store_version);
+				  &call->expected_version, NULL);
 	/* xdr_decode_AFSVolSync(&bp, call->reply[X]); */
 
 	afs_pages_written_back(vnode, call);
@@ -1183,7 +1197,7 @@ static int afs_fs_store_data64(struct afs_fs_cursor *fc,
 	call->first_offset = offset;
 	call->last_to = to;
 	call->send_pages = true;
-	call->store_version = vnode->status.data_version + 1;
+	call->expected_version = vnode->status.data_version + 1;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -1258,7 +1272,7 @@ int afs_fs_store_data(struct afs_fs_cursor *fc, struct address_space *mapping,
 	call->first_offset = offset;
 	call->last_to = to;
 	call->send_pages = true;
-	call->store_version = vnode->status.data_version + 1;
+	call->expected_version = vnode->status.data_version + 1;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -1288,7 +1302,6 @@ int afs_fs_store_data(struct afs_fs_cursor *fc, struct address_space *mapping,
  */
 static int afs_deliver_fs_store_status(struct afs_call *call)
 {
-	afs_dataversion_t *store_version;
 	struct afs_vnode *vnode = call->reply[0];
 	const __be32 *bp;
 	int ret;
@@ -1300,12 +1313,9 @@ static int afs_deliver_fs_store_status(struct afs_call *call)
 		return ret;
 
 	/* unmarshall the reply once we've received all of it */
-	store_version = NULL;
-	if (call->operation_ID == FSSTOREDATA)
-		store_version = &call->store_version;
-
 	bp = call->buffer;
-	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, store_version);
+	xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode,
+				  &call->expected_version, NULL);
 	/* xdr_decode_AFSVolSync(&bp, call->reply[X]); */
 
 	_leave(" = 0 [done]");
@@ -1360,7 +1370,7 @@ static int afs_fs_setattr_size64(struct afs_fs_cursor *fc, struct iattr *attr)
 
 	call->key = fc->key;
 	call->reply[0] = vnode;
-	call->store_version = vnode->status.data_version + 1;
+	call->expected_version = vnode->status.data_version + 1;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -1409,7 +1419,7 @@ static int afs_fs_setattr_size(struct afs_fs_cursor *fc, struct iattr *attr)
 
 	call->key = fc->key;
 	call->reply[0] = vnode;
-	call->store_version = vnode->status.data_version + 1;
+	call->expected_version = vnode->status.data_version + 1;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -1454,6 +1464,7 @@ int afs_fs_setattr(struct afs_fs_cursor *fc, struct iattr *attr)
 
 	call->key = fc->key;
 	call->reply[0] = vnode;
+	call->expected_version = vnode->status.data_version;
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -2004,7 +2015,8 @@ static int afs_deliver_fs_fetch_status(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	xdr_decode_AFSFetchStatus(&bp, status, vnode, NULL);
+	xdr_decode_AFSFetchStatus(&bp, status, vnode,
+				  &call->expected_version, NULL);
 	callback[call->count].version	= ntohl(bp[0]);
 	callback[call->count].expiry	= ntohl(bp[1]);
 	callback[call->count].type	= ntohl(bp[2]);
@@ -2056,6 +2068,7 @@ int afs_fs_fetch_status(struct afs_fs_cursor *fc,
 	call->reply[1] = status;
 	call->reply[2] = callback;
 	call->reply[3] = volsync;
+	call->expected_version = 1; /* vnode->status.data_version */
 
 	/* marshall the parameters */
 	bp = call->request;
@@ -2116,7 +2129,7 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
 		statuses = call->reply[1];
 		xdr_decode_AFSFetchStatus(&bp, &statuses[call->count],
 					  call->count == 0 ? vnode : NULL,
-					  NULL);
+					  NULL, NULL);
 
 		call->count++;
 		if (call->count < call->count2)
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index bcaff40..488abd7 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -105,7 +105,7 @@ static int afs_inode_map_status(struct afs_vnode *vnode, struct key *key)
 /*
  * Fetch file status from the volume.
  */
-int afs_fetch_status(struct afs_vnode *vnode, struct key *key)
+int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool new_inode)
 {
 	struct afs_fs_cursor fc;
 	int ret;
@@ -119,7 +119,7 @@ int afs_fetch_status(struct afs_vnode *vnode, struct key *key)
 	if (afs_begin_vnode_operation(&fc, vnode, key)) {
 		while (afs_select_fileserver(&fc)) {
 			fc.cb_break = vnode->cb_break + vnode->cb_s_break;
-			afs_fs_fetch_file_status(&fc, NULL);
+			afs_fs_fetch_file_status(&fc, NULL, new_inode);
 		}
 
 		afs_check_for_remote_deletion(&fc, fc.vnode);
@@ -307,7 +307,7 @@ struct inode *afs_iget(struct super_block *sb, struct key *key,
 
 	if (!status) {
 		/* it's a remotely extant inode */
-		ret = afs_fetch_status(vnode, key);
+		ret = afs_fetch_status(vnode, key, true);
 		if (ret < 0)
 			goto bad_inode;
 	} else {
@@ -432,7 +432,7 @@ int afs_validate(struct afs_vnode *vnode, struct key *key)
 	 * access */
 	if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
 		_debug("not promised");
-		ret = afs_fetch_status(vnode, key);
+		ret = afs_fetch_status(vnode, key, false);
 		if (ret < 0) {
 			if (ret == -ENOENT) {
 				set_bit(AFS_VNODE_DELETED, &vnode->flags);
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index ca65f12..6b72807 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -122,7 +122,8 @@ struct afs_call {
 	u32			operation_ID;	/* operation ID for an incoming call */
 	u32			count;		/* count for use in unmarshalling */
 	__be32			tmp;		/* place to extract temporary data */
-	afs_dataversion_t	store_version;	/* updated version expected from store */
+	afs_dataversion_t	expected_version; /* Updated version expected from store */
+	afs_dataversion_t	expected_version_2; /* 2nd updated version expected from store */
 };
 
 struct afs_call_type {
@@ -173,6 +174,7 @@ struct afs_read {
 	loff_t			len;		/* How much we're asking for */
 	loff_t			actual_len;	/* How much we're actually getting */
 	loff_t			remain;		/* Amount remaining */
+	afs_dataversion_t	new_version;	/* Version number returned by server */
 	atomic_t		usage;
 	unsigned int		index;		/* Which page we're reading into */
 	unsigned int		nr_pages;
@@ -702,7 +704,7 @@ extern int afs_flock(struct file *, int, struct file_lock *);
 /*
  * fsclient.c
  */
-extern int afs_fs_fetch_file_status(struct afs_fs_cursor *, struct afs_volsync *);
+extern int afs_fs_fetch_file_status(struct afs_fs_cursor *, struct afs_volsync *, bool);
 extern int afs_fs_give_up_callbacks(struct afs_net *, struct afs_server *);
 extern int afs_fs_fetch_data(struct afs_fs_cursor *, struct afs_read *);
 extern int afs_fs_create(struct afs_fs_cursor *, const char *, umode_t,
@@ -735,7 +737,7 @@ extern int afs_fs_fetch_status(struct afs_fs_cursor *, struct afs_net *,
 /*
  * inode.c
  */
-extern int afs_fetch_status(struct afs_vnode *, struct key *);
+extern int afs_fetch_status(struct afs_vnode *, struct key *, bool);
 extern int afs_iget5_test(struct inode *, void *);
 extern struct inode *afs_iget_pseudo_dir(struct super_block *, bool);
 extern struct inode *afs_iget(struct super_block *, struct key *,
diff --git a/fs/afs/security.c b/fs/afs/security.c
index bd82c5b..cea2fff 100644
--- a/fs/afs/security.c
+++ b/fs/afs/security.c
@@ -322,7 +322,7 @@ int afs_check_permit(struct afs_vnode *vnode, struct key *key,
 		 */
 		_debug("no valid permit");
 
-		ret = afs_fetch_status(vnode, key);
+		ret = afs_fetch_status(vnode, key, false);
 		if (ret < 0) {
 			*_access = 0;
 			_leave(" = %d", ret);