afs: Prospectively look up extra files when doing a single lookup

When afs_lookup() is called, prospectively look up the next 50 uncached
fids also from that same directory and cache the results, rather than just
looking up the one file requested.

This allows us to use the FS.InlineBulkStatus RPC op to increase efficiency
by fetching up to 50 file statuses at a time.

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

1 files changed, 266 insertions, 6 deletions

diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 88ec38c2d83c..75554ee98d02 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -94,7 +94,7 @@ static void xdr_decode_AFSFetchStatus(const __be32 **_bp,
 	data_version |= (u64) ntohl(*bp++) << 32;
 	EXTRACT(status->lock_count);
 	size |= (u64) ntohl(*bp++) << 32;
-	bp++; /* spare 4 */
+	EXTRACT(status->abort_code); /* spare 4 */
 	*_bp = bp;
 
 	if (size != status->size) {
@@ -274,7 +274,7 @@ static void xdr_decode_AFSFetchVolumeStatus(const __be32 **_bp,
 /*
  * deliver reply data to an FS.FetchStatus
  */
-static int afs_deliver_fs_fetch_status(struct afs_call *call)
+static int afs_deliver_fs_fetch_status_vnode(struct afs_call *call)
 {
 	struct afs_vnode *vnode = call->reply[0];
 	const __be32 *bp;
@@ -300,10 +300,10 @@ static int afs_deliver_fs_fetch_status(struct afs_call *call)
 /*
  * FS.FetchStatus operation type
  */
-static const struct afs_call_type afs_RXFSFetchStatus = {
-	.name		= "FS.FetchStatus",
+static const struct afs_call_type afs_RXFSFetchStatus_vnode = {
+	.name		= "FS.FetchStatus(vnode)",
 	.op		= afs_FS_FetchStatus,
-	.deliver	= afs_deliver_fs_fetch_status,
+	.deliver	= afs_deliver_fs_fetch_status_vnode,
 	.destructor	= afs_flat_call_destructor,
 };
 
@@ -320,7 +320,8 @@ int afs_fs_fetch_file_status(struct afs_fs_cursor *fc, struct afs_volsync *volsy
 	_enter(",%x,{%x:%u},,",
 	       key_serial(fc->key), vnode->fid.vid, vnode->fid.vnode);
 
-	call = afs_alloc_flat_call(net, &afs_RXFSFetchStatus, 16, (21 + 3 + 6) * 4);
+	call = afs_alloc_flat_call(net, &afs_RXFSFetchStatus_vnode,
+				   16, (21 + 3 + 6) * 4);
 	if (!call) {
 		fc->ac.error = -ENOMEM;
 		return -ENOMEM;
@@ -1947,3 +1948,262 @@ int afs_fs_get_capabilities(struct afs_net *net,
 	trace_afs_make_fs_call(call, NULL);
 	return afs_make_call(ac, call, GFP_NOFS, false);
 }
+
+/*
+ * Deliver reply data to an FS.FetchStatus with no vnode.
+ */
+static int afs_deliver_fs_fetch_status(struct afs_call *call)
+{
+	struct afs_file_status *status = call->reply[1];
+	struct afs_callback *callback = call->reply[2];
+	struct afs_volsync *volsync = call->reply[3];
+	struct afs_vnode *vnode = call->reply[0];
+	const __be32 *bp;
+	int ret;
+
+	ret = afs_transfer_reply(call);
+	if (ret < 0)
+		return ret;
+
+	_enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
+
+	/* unmarshall the reply once we've received all of it */
+	bp = call->buffer;
+	xdr_decode_AFSFetchStatus(&bp, status, vnode, NULL);
+	callback[call->count].version	= ntohl(bp[0]);
+	callback[call->count].expiry	= ntohl(bp[1]);
+	callback[call->count].type	= ntohl(bp[2]);
+	if (vnode)
+		xdr_decode_AFSCallBack(call, vnode, &bp);
+	else
+		bp += 3;
+	if (volsync)
+		xdr_decode_AFSVolSync(&bp, volsync);
+
+	_leave(" = 0 [done]");
+	return 0;
+}
+
+/*
+ * FS.FetchStatus operation type
+ */
+static const struct afs_call_type afs_RXFSFetchStatus = {
+	.name		= "FS.FetchStatus",
+	.op		= afs_FS_FetchStatus,
+	.deliver	= afs_deliver_fs_fetch_status,
+	.destructor	= afs_flat_call_destructor,
+};
+
+/*
+ * Fetch the status information for a fid without needing a vnode handle.
+ */
+int afs_fs_fetch_status(struct afs_fs_cursor *fc,
+			struct afs_net *net,
+			struct afs_fid *fid,
+			struct afs_file_status *status,
+			struct afs_callback *callback,
+			struct afs_volsync *volsync)
+{
+	struct afs_call *call;
+	__be32 *bp;
+
+	_enter(",%x,{%x:%u},,",
+	       key_serial(fc->key), fid->vid, fid->vnode);
+
+	call = afs_alloc_flat_call(net, &afs_RXFSFetchStatus, 16, (21 + 3 + 6) * 4);
+	if (!call) {
+		fc->ac.error = -ENOMEM;
+		return -ENOMEM;
+	}
+
+	call->key = fc->key;
+	call->reply[0] = NULL; /* vnode for fid[0] */
+	call->reply[1] = status;
+	call->reply[2] = callback;
+	call->reply[3] = volsync;
+
+	/* marshall the parameters */
+	bp = call->request;
+	bp[0] = htonl(FSFETCHSTATUS);
+	bp[1] = htonl(fid->vid);
+	bp[2] = htonl(fid->vnode);
+	bp[3] = htonl(fid->unique);
+
+	call->cb_break = fc->cb_break;
+	afs_use_fs_server(call, fc->cbi);
+	trace_afs_make_fs_call(call, fid);
+	return afs_make_call(&fc->ac, call, GFP_NOFS, false);
+}
+
+/*
+ * Deliver reply data to an FS.InlineBulkStatus call
+ */
+static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
+{
+	struct afs_file_status *statuses;
+	struct afs_callback *callbacks;
+	struct afs_vnode *vnode = call->reply[0];
+	const __be32 *bp;
+	u32 tmp;
+	int ret;
+
+	_enter("{%u}", call->unmarshall);
+
+	switch (call->unmarshall) {
+	case 0:
+		call->offset = 0;
+		call->unmarshall++;
+
+		/* Extract the file status count and array in two steps */
+	case 1:
+		_debug("extract status count");
+		ret = afs_extract_data(call, &call->tmp, 4, true);
+		if (ret < 0)
+			return ret;
+
+		tmp = ntohl(call->tmp);
+		_debug("status count: %u/%u", tmp, call->count2);
+		if (tmp != call->count2)
+			return -EBADMSG;
+
+		call->count = 0;
+		call->unmarshall++;
+	more_counts:
+		call->offset = 0;
+
+	case 2:
+		_debug("extract status array %u", call->count);
+		ret = afs_extract_data(call, call->buffer, 21 * 4, true);
+		if (ret < 0)
+			return ret;
+
+		bp = call->buffer;
+		statuses = call->reply[1];
+		xdr_decode_AFSFetchStatus(&bp, &statuses[call->count],
+					  call->count == 0 ? vnode : NULL,
+					  NULL);
+
+		call->count++;
+		if (call->count < call->count2)
+			goto more_counts;
+
+		call->count = 0;
+		call->unmarshall++;
+		call->offset = 0;
+
+		/* Extract the callback count and array in two steps */
+	case 3:
+		_debug("extract CB count");
+		ret = afs_extract_data(call, &call->tmp, 4, true);
+		if (ret < 0)
+			return ret;
+
+		tmp = ntohl(call->tmp);
+		_debug("CB count: %u", tmp);
+		if (tmp != call->count2)
+			return -EBADMSG;
+		call->count = 0;
+		call->unmarshall++;
+	more_cbs:
+		call->offset = 0;
+
+	case 4:
+		_debug("extract CB array");
+		ret = afs_extract_data(call, call->buffer, 3 * 4, true);
+		if (ret < 0)
+			return ret;
+
+		_debug("unmarshall CB array");
+		bp = call->buffer;
+		callbacks = call->reply[2];
+		callbacks[call->count].version	= ntohl(bp[0]);
+		callbacks[call->count].expiry	= ntohl(bp[1]);
+		callbacks[call->count].type	= ntohl(bp[2]);
+		statuses = call->reply[1];
+		if (call->count == 0 && vnode && statuses[0].abort_code == 0)
+			xdr_decode_AFSCallBack(call, vnode, &bp);
+		call->count++;
+		if (call->count < call->count2)
+			goto more_cbs;
+
+		call->offset = 0;
+		call->unmarshall++;
+
+	case 5:
+		ret = afs_extract_data(call, call->buffer, 6 * 4, false);
+		if (ret < 0)
+			return ret;
+
+		bp = call->buffer;
+		if (call->reply[3])
+			xdr_decode_AFSVolSync(&bp, call->reply[3]);
+
+		call->offset = 0;
+		call->unmarshall++;
+
+	case 6:
+		break;
+	}
+
+	_leave(" = 0 [done]");
+	return 0;
+}
+
+/*
+ * FS.InlineBulkStatus operation type
+ */
+static const struct afs_call_type afs_RXFSInlineBulkStatus = {
+	.name		= "FS.InlineBulkStatus",
+	.op		= afs_FS_InlineBulkStatus,
+	.deliver	= afs_deliver_fs_inline_bulk_status,
+	.destructor	= afs_flat_call_destructor,
+};
+
+/*
+ * Fetch the status information for up to 50 files
+ */
+int afs_fs_inline_bulk_status(struct afs_fs_cursor *fc,
+			      struct afs_net *net,
+			      struct afs_fid *fids,
+			      struct afs_file_status *statuses,
+			      struct afs_callback *callbacks,
+			      unsigned int nr_fids,
+			      struct afs_volsync *volsync)
+{
+	struct afs_call *call;
+	__be32 *bp;
+	int i;
+
+	_enter(",%x,{%x:%u},%u",
+	       key_serial(fc->key), fids[0].vid, fids[1].vnode, nr_fids);
+
+	call = afs_alloc_flat_call(net, &afs_RXFSInlineBulkStatus,
+				   (2 + nr_fids * 3) * 4,
+				   21 * 4);
+	if (!call) {
+		fc->ac.error = -ENOMEM;
+		return -ENOMEM;
+	}
+
+	call->key = fc->key;
+	call->reply[0] = NULL; /* vnode for fid[0] */
+	call->reply[1] = statuses;
+	call->reply[2] = callbacks;
+	call->reply[3] = volsync;
+	call->count2 = nr_fids;
+
+	/* marshall the parameters */
+	bp = call->request;
+	*bp++ = htonl(FSINLINEBULKSTATUS);
+	*bp++ = htonl(nr_fids);
+	for (i = 0; i < nr_fids; i++) {
+		*bp++ = htonl(fids[i].vid);
+		*bp++ = htonl(fids[i].vnode);
+		*bp++ = htonl(fids[i].unique);
+	}
+
+	call->cb_break = fc->cb_break;
+	afs_use_fs_server(call, fc->cbi);
+	trace_afs_make_fs_call(call, &fids[0]);
+	return afs_make_call(&fc->ac, call, GFP_NOFS, false);
+}