libceph: introduce ceph_pagelist_alloc()

struct ceph_pagelist cannot be embedded into anything else because it
has its own refcount. Merge allocation and initialization together.

Signed-off-by: Ilya Dryomov <[e-mail]>

fs/ceph/acl.c

···
 	tmp_buf = kmalloc(max(val_size1, val_size2), GFP_KERNEL);
 	if (!tmp_buf)
 		goto out_err;
-	pagelist = kmalloc(sizeof(struct ceph_pagelist), GFP_KERNEL);
+	pagelist = ceph_pagelist_alloc(GFP_KERNEL);
 	if (!pagelist)
 		goto out_err;
-	ceph_pagelist_init(pagelist);
 
 	err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
 	if (err)

fs/ceph/mds_client.c

···
 
 	pr_info("mds%d reconnect start\n", mds);
 
-	pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
+	pagelist = ceph_pagelist_alloc(GFP_NOFS);
 	if (!pagelist)
 		goto fail_nopagelist;
-	ceph_pagelist_init(pagelist);
 
 	reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, GFP_NOFS, false);
 	if (!reply)

fs/ceph/xattr.c

···
 
 	if (size > 0) {
 		/* copy value into pagelist */
-		pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
+		pagelist = ceph_pagelist_alloc(GFP_NOFS);
 		if (!pagelist)
 			return -ENOMEM;
 
-		ceph_pagelist_init(pagelist);
 		err = ceph_pagelist_append(pagelist, value, size);
 		if (err)
 			goto out;

include/linux/ceph/pagelist.h

···
 	size_t room;		    /* room remaining to reset to */
 };
 
-static inline void ceph_pagelist_init(struct ceph_pagelist *pl)
-{
-	INIT_LIST_HEAD(&pl->head);
-	pl->mapped_tail = NULL;
-	pl->length = 0;
-	pl->room = 0;
-	INIT_LIST_HEAD(&pl->free_list);
-	pl->num_pages_free = 0;
-	refcount_set(&pl->refcnt, 1);
-}
+struct ceph_pagelist *ceph_pagelist_alloc(gfp_t gfp_flags);
 
 extern void ceph_pagelist_release(struct ceph_pagelist *pl);
 

net/ceph/osd_client.c

···
 
 	op = _osd_req_op_init(osd_req, which, CEPH_OSD_OP_CALL, 0);
 
-	pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
+	pagelist = ceph_pagelist_alloc(GFP_NOFS);
 	if (!pagelist)
 		return -ENOMEM;
-
-	ceph_pagelist_init(pagelist);
 
 	op->cls.class_name = class;
 	size = strlen(class);
···
 
 	BUG_ON(opcode != CEPH_OSD_OP_SETXATTR && opcode != CEPH_OSD_OP_CMPXATTR);
 
-	pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
+	pagelist = ceph_pagelist_alloc(GFP_NOFS);
 	if (!pagelist)
 		return -ENOMEM;
-
-	ceph_pagelist_init(pagelist);
 
 	payload_len = strlen(name);
 	op->xattr.name_len = payload_len;
···
 
 	op = _osd_req_op_init(req, which, CEPH_OSD_OP_NOTIFY_ACK, 0);
 
-	pl = kmalloc(sizeof(*pl), GFP_NOIO);
+	pl = ceph_pagelist_alloc(GFP_NOIO);
 	if (!pl)
 		return -ENOMEM;
 
-	ceph_pagelist_init(pl);
 	ret = ceph_pagelist_encode_64(pl, notify_id);
 	ret |= ceph_pagelist_encode_64(pl, cookie);
 	if (payload) {
···
 	op = _osd_req_op_init(req, which, CEPH_OSD_OP_NOTIFY, 0);
 	op->notify.cookie = cookie;
 
-	pl = kmalloc(sizeof(*pl), GFP_NOIO);
+	pl = ceph_pagelist_alloc(GFP_NOIO);
 	if (!pl)
 		return -ENOMEM;
 
-	ceph_pagelist_init(pl);
 	ret = ceph_pagelist_encode_32(pl, 1); /* prot_ver */
 	ret |= ceph_pagelist_encode_32(pl, timeout);
 	ret |= ceph_pagelist_encode_32(pl, payload_len);

net/ceph/pagelist.c

···
 #include <linux/highmem.h>
 #include <linux/ceph/pagelist.h>
 
+struct ceph_pagelist *ceph_pagelist_alloc(gfp_t gfp_flags)
+{
+	struct ceph_pagelist *pl;
+
+	pl = kmalloc(sizeof(*pl), gfp_flags);
+	if (!pl)
+		return NULL;
+
+	INIT_LIST_HEAD(&pl->head);
+	pl->mapped_tail = NULL;
+	pl->length = 0;
+	pl->room = 0;
+	INIT_LIST_HEAD(&pl->free_list);
+	pl->num_pages_free = 0;
+	refcount_set(&pl->refcnt, 1);
+
+	return pl;
+}
+EXPORT_SYMBOL(ceph_pagelist_alloc);
+
 static void ceph_pagelist_unmap_tail(struct ceph_pagelist *pl)
 {
 	if (pl->mapped_tail) {