btrfs: use list_for_each_entry* in check-integrity.c

Use list_for_each_entry*() instead of list_for_each*() to simplify
the code.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index 0340c57bf37778f6983645803c3f381ae1a27a2a..861d472564c1960ff973c41e2eccdabb38785d28 100644 (file)
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -531,13 +531,9 @@ static struct btrfsic_block *btrfsic_block_hashtable_lookup(
            (((unsigned int)(dev_bytenr >> 16)) ^
             ((unsigned int)((uintptr_t)bdev))) &
             (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1);
-       struct list_head *elem;
-
-       list_for_each(elem, h->table + hashval) {
-               struct btrfsic_block *const b =
-                   list_entry(elem, struct btrfsic_block,
-                              collision_resolving_node);
+       struct btrfsic_block *b;
 
+       list_for_each_entry(b, h->table + hashval, collision_resolving_node) {
                if (b->dev_state->bdev == bdev && b->dev_bytenr == dev_bytenr)
                        return b;
        }
@@ -588,13 +584,9 @@ static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup(
             ((unsigned int)((uintptr_t)bdev_ref_to)) ^
             ((unsigned int)((uintptr_t)bdev_ref_from))) &
             (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1);
-       struct list_head *elem;
-
-       list_for_each(elem, h->table + hashval) {
-               struct btrfsic_block_link *const l =
-                   list_entry(elem, struct btrfsic_block_link,
-                              collision_resolving_node);
+       struct btrfsic_block_link *l;
 
+       list_for_each_entry(l, h->table + hashval, collision_resolving_node) {
                BUG_ON(NULL == l->block_ref_to);
                BUG_ON(NULL == l->block_ref_from);
                if (l->block_ref_to->dev_state->bdev == bdev_ref_to &&
@@ -639,13 +631,9 @@ static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
        const unsigned int hashval =
            (((unsigned int)((uintptr_t)bdev)) &
             (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
-       struct list_head *elem;
-
-       list_for_each(elem, h->table + hashval) {
-               struct btrfsic_dev_state *const ds =
-                   list_entry(elem, struct btrfsic_dev_state,
-                              collision_resolving_node);
+       struct btrfsic_dev_state *ds;
 
+       list_for_each_entry(ds, h->table + hashval, collision_resolving_node) {
                if (ds->bdev == bdev)
                        return ds;
        }
@@ -1720,29 +1708,20 @@ static int btrfsic_read_block(struct btrfsic_state *state,
 
 static void btrfsic_dump_database(struct btrfsic_state *state)
 {
-       struct list_head *elem_all;
+       const struct btrfsic_block *b_all;
 
        BUG_ON(NULL == state);
 
        printk(KERN_INFO "all_blocks_list:\n");
-       list_for_each(elem_all, &state->all_blocks_list) {
-               const struct btrfsic_block *const b_all =
-                   list_entry(elem_all, struct btrfsic_block,
-                              all_blocks_node);
-               struct list_head *elem_ref_to;
-               struct list_head *elem_ref_from;
+       list_for_each_entry(b_all, &state->all_blocks_list, all_blocks_node) {
+               const struct btrfsic_block_link *l;
 
                printk(KERN_INFO "%c-block @%llu (%s/%llu/%d)\n",
                       btrfsic_get_block_type(state, b_all),
                       b_all->logical_bytenr, b_all->dev_state->name,
                       b_all->dev_bytenr, b_all->mirror_num);
 
-               list_for_each(elem_ref_to, &b_all->ref_to_list) {
-                       const struct btrfsic_block_link *const l =
-                           list_entry(elem_ref_to,
-                                      struct btrfsic_block_link,
-                                      node_ref_to);
-
+               list_for_each_entry(l, &b_all->ref_to_list, node_ref_to) {
                        printk(KERN_INFO " %c @%llu (%s/%llu/%d)"
                               " refers %u* to"
                               " %c @%llu (%s/%llu/%d)\n",
@@ -1757,12 +1736,7 @@ static void btrfsic_dump_database(struct btrfsic_state *state)
                               l->block_ref_to->mirror_num);
                }
 
-               list_for_each(elem_ref_from, &b_all->ref_from_list) {
-                       const struct btrfsic_block_link *const l =
-                           list_entry(elem_ref_from,
-                                      struct btrfsic_block_link,
-                                      node_ref_from);
-
+               list_for_each_entry(l, &b_all->ref_from_list, node_ref_from) {
                        printk(KERN_INFO " %c @%llu (%s/%llu/%d)"
                               " is ref %u* from"
                               " %c @%llu (%s/%llu/%d)\n",
@@ -1845,8 +1819,7 @@ again:
                                               &state->block_hashtable);
        if (NULL != block) {
                u64 bytenr = 0;
-               struct list_head *elem_ref_to;
-               struct list_head *tmp_ref_to;
+               struct btrfsic_block_link *l, *tmp;
 
                if (block->is_superblock) {
                        bytenr = btrfs_super_bytenr((struct btrfs_super_block *)
@@ -1967,13 +1940,8 @@ again:
                 * because it still carries valueable information
                 * like whether it was ever written and IO completed.
                 */
-               list_for_each_safe(elem_ref_to, tmp_ref_to,
-                                  &block->ref_to_list) {
-                       struct btrfsic_block_link *const l =
-                           list_entry(elem_ref_to,
-                                      struct btrfsic_block_link,
-                                      node_ref_to);
-
+               list_for_each_entry_safe(l, tmp, &block->ref_to_list,
+                                        node_ref_to) {
                        if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
                                btrfsic_print_rem_link(state, l);
                        l->ref_cnt--;
@@ -2436,7 +2404,7 @@ static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
                                        struct btrfsic_block *const block,
                                        int recursion_level)
 {
-       struct list_head *elem_ref_to;
+       const struct btrfsic_block_link *l;
        int ret = 0;
 
        if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
@@ -2464,11 +2432,7 @@ static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
         * This algorithm is recursive because the amount of used stack
         * space is very small and the max recursion depth is limited.
         */
-       list_for_each(elem_ref_to, &block->ref_to_list) {
-               const struct btrfsic_block_link *const l =
-                   list_entry(elem_ref_to, struct btrfsic_block_link,
-                              node_ref_to);
-
+       list_for_each_entry(l, &block->ref_to_list, node_ref_to) {
                if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
                        printk(KERN_INFO
                               "rl=%d, %c @%llu (%s/%llu/%d)"
@@ -2561,7 +2525,7 @@ static int btrfsic_is_block_ref_by_superblock(
                const struct btrfsic_block *block,
                int recursion_level)
 {
-       struct list_head *elem_ref_from;
+       const struct btrfsic_block_link *l;
 
        if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
                /* refer to comment at "abort cyclic linkage (case 1)" */
@@ -2576,11 +2540,7 @@ static int btrfsic_is_block_ref_by_superblock(
         * This algorithm is recursive because the amount of used stack space
         * is very small and the max recursion depth is limited.
         */
-       list_for_each(elem_ref_from, &block->ref_from_list) {
-               const struct btrfsic_block_link *const l =
-                   list_entry(elem_ref_from, struct btrfsic_block_link,
-                              node_ref_from);
-
+       list_for_each_entry(l, &block->ref_from_list, node_ref_from) {
                if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
                        printk(KERN_INFO
                               "rl=%d, %c @%llu (%s/%llu/%d)"
@@ -2669,7 +2629,7 @@ static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
                                  const struct btrfsic_block *block,
                                  int indent_level)
 {
-       struct list_head *elem_ref_to;
+       const struct btrfsic_block_link *l;
        int indent_add;
        static char buf[80];
        int cursor_position;
@@ -2704,11 +2664,7 @@ static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
        }
 
        cursor_position = indent_level;
-       list_for_each(elem_ref_to, &block->ref_to_list) {
-               const struct btrfsic_block_link *const l =
-                   list_entry(elem_ref_to, struct btrfsic_block_link,
-                              node_ref_to);
-
+       list_for_each_entry(l, &block->ref_to_list, node_ref_to) {
                while (cursor_position < indent_level) {
                        printk(" ");
                        cursor_position++;
@@ -3165,8 +3121,7 @@ int btrfsic_mount(struct btrfs_root *root,
 void btrfsic_unmount(struct btrfs_root *root,
                     struct btrfs_fs_devices *fs_devices)
 {
-       struct list_head *elem_all;
-       struct list_head *tmp_all;
+       struct btrfsic_block *b_all, *tmp_all;
        struct btrfsic_state *state;
        struct list_head *dev_head = &fs_devices->devices;
        struct btrfs_device *device;
@@ -3206,20 +3161,12 @@ void btrfsic_unmount(struct btrfs_root *root,
         * just free all memory that was allocated dynamically.
         * Free the blocks and the block_links.
         */
-       list_for_each_safe(elem_all, tmp_all, &state->all_blocks_list) {
-               struct btrfsic_block *const b_all =
-                   list_entry(elem_all, struct btrfsic_block,
-                              all_blocks_node);
-               struct list_head *elem_ref_to;
-               struct list_head *tmp_ref_to;
-
-               list_for_each_safe(elem_ref_to, tmp_ref_to,
-                                  &b_all->ref_to_list) {
-                       struct btrfsic_block_link *const l =
-                           list_entry(elem_ref_to,
-                                      struct btrfsic_block_link,
-                                      node_ref_to);
+       list_for_each_entry_safe(b_all, tmp_all, &state->all_blocks_list,
+                                all_blocks_node) {
+               struct btrfsic_block_link *l, *tmp;
 
+               list_for_each_entry_safe(l, tmp, &b_all->ref_to_list,
+                                        node_ref_to) {
                        if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
                                btrfsic_print_rem_link(state, l);