btrfs: cleanup, use kmalloc_array/kcalloc array helpers

Convert kmalloc(nr * size, ..) to kmalloc_array that does additional
overflow checks, the zeroing variant is kcalloc.

Signed-off-by: David Sterba <[e-mail]>

fs/btrfs/check-integrity.c

···
 			       (unsigned long long)bio->bi_iter.bi_sector,
 			       dev_bytenr, bio->bi_bdev);
 
-		mapped_datav = kmalloc(sizeof(*mapped_datav) * bio->bi_vcnt,
-				       GFP_NOFS);
+		mapped_datav = kmalloc_array(bio->bi_vcnt,
+					     sizeof(*mapped_datav), GFP_NOFS);
 		if (!mapped_datav)
 			goto leave;
 		cur_bytenr = dev_bytenr;

fs/btrfs/compression.c

···
 	cb->orig_bio = bio;
 
 	nr_pages = DIV_ROUND_UP(compressed_len, PAGE_CACHE_SIZE);
-	cb->compressed_pages = kzalloc(sizeof(struct page *) * nr_pages,
+	cb->compressed_pages = kcalloc(nr_pages, sizeof(struct page *),
 				       GFP_NOFS);
 	if (!cb->compressed_pages)
 		goto fail1;

fs/btrfs/ctree.c

···
 	if (!tree_mod_need_log(fs_info, eb))
 		return 0;
 
-	tm_list = kzalloc(nr_items * sizeof(struct tree_mod_elem *), flags);
+	tm_list = kcalloc(nr_items, sizeof(struct tree_mod_elem *), flags);
 	if (!tm_list)
 		return -ENOMEM;
 
···
 
 	if (log_removal && btrfs_header_level(old_root) > 0) {
 		nritems = btrfs_header_nritems(old_root);
-		tm_list = kzalloc(nritems * sizeof(struct tree_mod_elem *),
+		tm_list = kcalloc(nritems, sizeof(struct tree_mod_elem *),
 				  flags);
 		if (!tm_list) {
 			ret = -ENOMEM;
···
 	if (btrfs_header_level(dst) == 0 && btrfs_header_level(src) == 0)
 		return 0;
 
-	tm_list = kzalloc(nr_items * 2 * sizeof(struct tree_mod_elem *),
+	tm_list = kcalloc(nr_items * 2, sizeof(struct tree_mod_elem *),
 			  GFP_NOFS);
 	if (!tm_list)
 		return -ENOMEM;
···
 		return 0;
 
 	nritems = btrfs_header_nritems(eb);
-	tm_list = kzalloc(nritems * sizeof(struct tree_mod_elem *),
-			  GFP_NOFS);
+	tm_list = kcalloc(nritems, sizeof(struct tree_mod_elem *), GFP_NOFS);
 	if (!tm_list)
 		return -ENOMEM;
 

fs/btrfs/disk-io.c

···
 		offset += cur_len;
 	}
 	if (csum_size > sizeof(inline_result)) {
-		result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
+		result = kzalloc(csum_size, GFP_NOFS);
 		if (!result)
 			return 1;
 	} else {

fs/btrfs/file-item.c

···
 	nblocks = bio->bi_iter.bi_size >> inode->i_sb->s_blocksize_bits;
 	if (!dst) {
 		if (nblocks * csum_size > BTRFS_BIO_INLINE_CSUM_SIZE) {
-			btrfs_bio->csum_allocated = kmalloc(nblocks * csum_size,
-							    GFP_NOFS);
+			btrfs_bio->csum_allocated = kmalloc_array(nblocks,
+					csum_size, GFP_NOFS);
 			if (!btrfs_bio->csum_allocated) {
 				btrfs_free_path(path);
 				return -ENOMEM;

fs/btrfs/file.c

···
 			PAGE_CACHE_SIZE / (sizeof(struct page *)));
 	nrptrs = min(nrptrs, current->nr_dirtied_pause - current->nr_dirtied);
 	nrptrs = max(nrptrs, 8);
-	pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
+	pages = kmalloc_array(nrptrs, sizeof(struct page *), GFP_KERNEL);
 	if (!pages)
 		return -ENOMEM;
 

fs/btrfs/free-space-cache.c

···
 
 	memset(io_ctl, 0, sizeof(struct io_ctl));
 
-	io_ctl->pages = kzalloc(sizeof(struct page *) * num_pages, GFP_NOFS);
+	io_ctl->pages = kcalloc(num_pages, sizeof(struct page *), GFP_NOFS);
 	if (!io_ctl->pages)
 		return -ENOMEM;
 

fs/btrfs/inode.c

···
 	 */
 	if (inode_need_compress(inode)) {
 		WARN_ON(pages);
-		pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
+		pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS);
 		if (!pages) {
 			/* just bail out to the uncompressed code */
 			goto cont;

fs/btrfs/raid56.c

···
 	int err;
 	int i;
 
-	pointers = kzalloc(rbio->real_stripes * sizeof(void *),
-			   GFP_NOFS);
+	pointers = kcalloc(rbio->real_stripes, sizeof(void *), GFP_NOFS);
 	if (!pointers) {
 		err = -ENOMEM;
 		goto cleanup_io;

fs/btrfs/scrub.c

···
 	 * the statistics.
 	 */
 
-	sblocks_for_recheck = kzalloc(BTRFS_MAX_MIRRORS *
-				     sizeof(*sblocks_for_recheck),
-				     GFP_NOFS);
+	sblocks_for_recheck = kcalloc(BTRFS_MAX_MIRRORS,
+				      sizeof(*sblocks_for_recheck), GFP_NOFS);
 	if (!sblocks_for_recheck) {
 		spin_lock(&sctx->stat_lock);
 		sctx->stat.malloc_errors++;

fs/btrfs/volumes.c

···
 	max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
 			     max_chunk_size);
 
-	devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices,
+	devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
 			       GFP_NOFS);
 	if (!devices_info)
 		return -ENOMEM;
···
 		rmap_len = map->stripe_len * nr_data_stripes(map);
 	}
 
-	buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
+	buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
 	BUG_ON(!buf); /* -ENOMEM */
 
 	for (i = 0; i < map->num_stripes; i++) {