2009-01-16 15:32:45

by Qinghuang Feng

[permalink] [raw]
Subject: [PATCH resend] Btrfs: simplify iteration codes

Merge list_for_each* and list_entry to list_for_each_entry*

Signed-off-by: Qinghuang Feng <[email protected]>
---
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 81a3138..aedfcec 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1136,7 +1136,6 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
{
struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
int ret = 0;
- struct list_head *cur;
struct btrfs_device *device;
struct backing_dev_info *bdi;
#if 0
@@ -1144,8 +1143,7 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
btrfs_congested_async(info, 0))
return 1;
#endif
- list_for_each(cur, &info->fs_devices->devices) {
- device = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
if (!device->bdev)
continue;
bdi = blk_get_backing_dev_info(device->bdev);
@@ -1163,13 +1161,11 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
*/
static void __unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
{
- struct list_head *cur;
struct btrfs_device *device;
struct btrfs_fs_info *info;

info = (struct btrfs_fs_info *)bdi->unplug_io_data;
- list_for_each(cur, &info->fs_devices->devices) {
- device = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
if (!device->bdev)
continue;

@@ -1995,7 +1991,6 @@ static int write_dev_supers(struct btrfs_device *device,

int write_all_supers(struct btrfs_root *root, int max_mirrors)
{
- struct list_head *cur;
struct list_head *head = &root->fs_info->fs_devices->devices;
struct btrfs_device *dev;
struct btrfs_super_block *sb;
@@ -2011,8 +2006,7 @@ int write_all_supers(struct btrfs_root *root, int max_mirrors)

sb = &root->fs_info->super_for_commit;
dev_item = &sb->dev_item;
- list_for_each(cur, head) {
- dev = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(dev, head, dev_list) {
if (!dev->bdev) {
total_errors++;
continue;
@@ -2045,8 +2039,7 @@ int write_all_supers(struct btrfs_root *root, int max_mirrors)
}

total_errors = 0;
- list_for_each(cur, head) {
- dev = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(dev, head, dev_list) {
if (!dev->bdev)
continue;
if (!dev->in_fs_metadata || !dev->writeable)
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 293da65..c8815c1 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -326,10 +326,8 @@ static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
u64 flags)
{
struct list_head *head = &info->space_info;
- struct list_head *cur;
struct btrfs_space_info *found;
- list_for_each(cur, head) {
- found = list_entry(cur, struct btrfs_space_info, list);
+ list_for_each_entry(found, head, list) {
if (found->flags == flags)
return found;
}
@@ -3014,7 +3012,6 @@ loop_check:
static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
{
struct btrfs_block_group_cache *cache;
- struct list_head *l;

printk(KERN_INFO "space_info has %llu free, is %sfull\n",
(unsigned long long)(info->total_bytes - info->bytes_used -
@@ -3022,8 +3019,7 @@ static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
(info->full) ? "" : "not ");

down_read(&info->groups_sem);
- list_for_each(l, &info->block_groups) {
- cache = list_entry(l, struct btrfs_block_group_cache, list);
+ list_for_each_entry(cache, &info->block_groups, list) {
spin_lock(&cache->lock);
printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
"%llu pinned %llu reserved\n",
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 8adfe05..72c9277 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1324,12 +1324,11 @@ static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
struct inode *inode, u64 file_offset,
struct list_head *list)
{
- struct list_head *cur;
struct btrfs_ordered_sum *sum;

btrfs_set_trans_block_group(trans, inode);
- list_for_each(cur, list) {
- sum = list_entry(cur, struct btrfs_ordered_sum, list);
+
+ list_for_each_entry(sum, list, list) {
btrfs_csum_file_blocks(trans,
BTRFS_I(inode)->root->fs_info->csum_root, sum);
}
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index a209401..77c2411 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -613,7 +613,6 @@ int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
struct btrfs_sector_sum *sector_sums;
struct btrfs_ordered_extent *ordered;
struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
- struct list_head *cur;
unsigned long num_sectors;
unsigned long i;
u32 sectorsize = BTRFS_I(inode)->root->sectorsize;
@@ -624,8 +623,7 @@ int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
return 1;

mutex_lock(&tree->mutex);
- list_for_each_prev(cur, &ordered->list) {
- ordered_sum = list_entry(cur, struct btrfs_ordered_sum, list);
+ list_for_each_entry_reverse(ordered_sum, &ordered->list, list) {
if (disk_bytenr >= ordered_sum->bytenr) {
num_sectors = ordered_sum->len / sectorsize;
sector_sums = ordered_sum->sums;
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 8a08f94..919172d 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -852,11 +852,9 @@ static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans,
{
struct btrfs_pending_snapshot *pending;
struct list_head *head = &trans->transaction->pending_snapshots;
- struct list_head *cur;
int ret;

- list_for_each(cur, head) {
- pending = list_entry(cur, struct btrfs_pending_snapshot, list);
+ list_for_each_entry(pending, head, list) {
ret = create_pending_snapshot(trans, fs_info, pending);
BUG_ON(ret);
}
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index b187b53..df88c91 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -104,10 +104,8 @@ static noinline struct btrfs_device *__find_device(struct list_head *head,
u64 devid, u8 *uuid)
{
struct btrfs_device *dev;
- struct list_head *cur;

- list_for_each(cur, head) {
- dev = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(dev, head, dev_list) {
if (dev->devid == devid &&
(!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
return dev;
@@ -118,11 +116,9 @@ static noinline struct btrfs_device *__find_device(struct list_head *head,

static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
{
- struct list_head *cur;
struct btrfs_fs_devices *fs_devices;

- list_for_each(cur, &fs_uuids) {
- fs_devices = list_entry(cur, struct btrfs_fs_devices, list);
+ list_for_each_entry(fs_devices, &fs_uuids, list) {
if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
return fs_devices;
}
@@ -345,13 +341,11 @@ error:
int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
{
struct list_head *tmp;
- struct list_head *cur;
- struct btrfs_device *device;
+ struct btrfs_device *device, *next;

mutex_lock(&uuid_mutex);
again:
- list_for_each_safe(cur, tmp, &fs_devices->devices) {
- device = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
if (device->in_fs_metadata)
continue;

@@ -382,14 +376,12 @@ again:

static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
{
- struct list_head *cur;
struct btrfs_device *device;

if (--fs_devices->opened > 0)
return 0;

- list_for_each(cur, &fs_devices->devices) {
- device = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(device, &fs_devices->devices, dev_list) {
if (device->bdev) {
close_bdev_exclusive(device->bdev, device->mode);
fs_devices->open_devices--;
@@ -438,7 +430,6 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
{
struct block_device *bdev;
struct list_head *head = &fs_devices->devices;
- struct list_head *cur;
struct btrfs_device *device;
struct block_device *latest_bdev = NULL;
struct buffer_head *bh;
@@ -449,8 +440,7 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
int seeding = 1;
int ret = 0;

- list_for_each(cur, head) {
- device = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(device, head, dev_list) {
if (device->bdev)
continue;
if (!device->name)
@@ -1016,14 +1006,12 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
}

if (strcmp(device_path, "missing") == 0) {
- struct list_head *cur;
struct list_head *devices;
struct btrfs_device *tmp;

device = NULL;
devices = &root->fs_info->fs_devices->devices;
- list_for_each(cur, devices) {
- tmp = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(tmp, devices, dev_list) {
if (tmp->in_fs_metadata && !tmp->bdev) {
device = tmp;
break;
@@ -1279,7 +1267,6 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
struct btrfs_trans_handle *trans;
struct btrfs_device *device;
struct block_device *bdev;
- struct list_head *cur;
struct list_head *devices;
struct super_block *sb = root->fs_info->sb;
u64 total_bytes;
@@ -1303,8 +1290,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
mutex_lock(&root->fs_info->volume_mutex);

devices = &root->fs_info->fs_devices->devices;
- list_for_each(cur, devices) {
- device = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(device, devices, dev_list) {
if (device->bdev == bdev) {
ret = -EEXIST;
goto error;
@@ -1703,7 +1689,6 @@ static u64 div_factor(u64 num, int factor)
int btrfs_balance(struct btrfs_root *dev_root)
{
int ret;
- struct list_head *cur;
struct list_head *devices = &dev_root->fs_info->fs_devices->devices;
struct btrfs_device *device;
u64 old_size;
@@ -1722,8 +1707,7 @@ int btrfs_balance(struct btrfs_root *dev_root)
dev_root = dev_root->fs_info->dev_root;

/* step one make some room on all the devices */
- list_for_each(cur, devices) {
- device = list_entry(cur, struct btrfs_device, dev_list);
+ list_for_each_entry(device, devices, dev_list) {
old_size = device->total_bytes;
size_to_free = div_factor(old_size, 1);
size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);