[PATCH v4.19.y 1/2] btrfs: merge btrfs_find_device and find_device

From: Vikash Bansal
Date: Tue Jun 09 2020 - 02:54:11 EST


From: Anand Jain <anand.jain@xxxxxxxxxx>

commit 09ba3bc9dd150457c506e4661380a6183af651c1 upstream

Both btrfs_find_device() and find_device() does the same thing except
that the latter does not take the seed device onto account in the device
scanning context. We can merge them.

Signed-off-by: Anand Jain <anand.jain@xxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
[4.19.y backport notes:
Vikash : - To apply this patch, a portion of commit e4319cd9cace
was used to change the first argument of function
"btrfs_find_device" from "struct btrfs_fs_info" to
"struct btrfs_fs_devices".
Signed-off-by: Vikash Bansal <bvikas@xxxxxxxxxx>
---
fs/btrfs/dev-replace.c | 8 ++--
fs/btrfs/ioctl.c | 5 ++-
fs/btrfs/scrub.c | 4 +-
fs/btrfs/volumes.c | 84 +++++++++++++++++++++---------------------
fs/btrfs/volumes.h | 4 +-
5 files changed, 53 insertions(+), 52 deletions(-)

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 96763805787e..1b9c8ffb038f 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -112,11 +112,11 @@ int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info)
break;
case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
- dev_replace->srcdev = btrfs_find_device(fs_info, src_devid,
- NULL, NULL);
- dev_replace->tgtdev = btrfs_find_device(fs_info,
+ dev_replace->srcdev = btrfs_find_device(fs_info->fs_devices,
+ src_devid, NULL, NULL, true);
+ dev_replace->tgtdev = btrfs_find_device(fs_info->fs_devices,
BTRFS_DEV_REPLACE_DEVID,
- NULL, NULL);
+ NULL, NULL, true);
/*
* allow 'btrfs dev replace_cancel' if src/tgt device is
* missing
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 199c70b8f7d8..a5ae02bf3652 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1642,7 +1642,7 @@ static noinline int btrfs_ioctl_resize(struct file *file,
btrfs_info(fs_info, "resizing devid %llu", devid);
}

- device = btrfs_find_device(fs_info, devid, NULL, NULL);
+ device = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
if (!device) {
btrfs_info(fs_info, "resizer unable to find device %llu",
devid);
@@ -3178,7 +3178,8 @@ static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
s_uuid = di_args->uuid;

rcu_read_lock();
- dev = btrfs_find_device(fs_info, di_args->devid, s_uuid, NULL);
+ dev = btrfs_find_device(fs_info->fs_devices, di_args->devid, s_uuid,
+ NULL, true);

if (!dev) {
ret = -ENODEV;
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 6b6008db3e03..fee8995c9a0c 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -3835,7 +3835,7 @@ int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
return PTR_ERR(sctx);

mutex_lock(&fs_info->fs_devices->device_list_mutex);
- dev = btrfs_find_device(fs_info, devid, NULL, NULL);
+ dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
if (!dev || (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) &&
!is_dev_replace)) {
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
@@ -4019,7 +4019,7 @@ int btrfs_scrub_progress(struct btrfs_fs_info *fs_info, u64 devid,
struct scrub_ctx *sctx = NULL;

mutex_lock(&fs_info->fs_devices->device_list_mutex);
- dev = btrfs_find_device(fs_info, devid, NULL, NULL);
+ dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
if (dev)
sctx = dev->scrub_ctx;
if (sctx)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 9c3b394b99fa..5b0d00c63fbb 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -347,27 +347,6 @@ static struct btrfs_device *__alloc_device(void)
return dev;
}

-/*
- * Find a device specified by @devid or @uuid in the list of @fs_devices, or
- * return NULL.
- *
- * If devid and uuid are both specified, the match must be exact, otherwise
- * only devid is used.
- */
-static struct btrfs_device *find_device(struct btrfs_fs_devices *fs_devices,
- u64 devid, const u8 *uuid)
-{
- struct btrfs_device *dev;
-
- list_for_each_entry(dev, &fs_devices->devices, dev_list) {
- if (dev->devid == devid &&
- (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
- return dev;
- }
- }
- return NULL;
-}
-
static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
{
struct btrfs_fs_devices *fs_devices;
@@ -772,8 +751,8 @@ static noinline struct btrfs_device *device_list_add(const char *path,
device = NULL;
} else {
mutex_lock(&fs_devices->device_list_mutex);
- device = find_device(fs_devices, devid,
- disk_super->dev_item.uuid);
+ device = btrfs_find_device(fs_devices, devid,
+ disk_super->dev_item.uuid, NULL, false);
}

if (!device) {
@@ -2144,7 +2123,8 @@ static int btrfs_find_device_by_path(struct btrfs_fs_info *fs_info,
disk_super = (struct btrfs_super_block *)bh->b_data;
devid = btrfs_stack_device_id(&disk_super->dev_item);
dev_uuid = disk_super->dev_item.uuid;
- *device = btrfs_find_device(fs_info, devid, dev_uuid, disk_super->fsid);
+ *device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid,
+ disk_super->fsid, true);
brelse(bh);
if (!*device)
ret = -ENOENT;
@@ -2190,7 +2170,8 @@ int btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info, u64 devid,

if (devid) {
ret = 0;
- *device = btrfs_find_device(fs_info, devid, NULL, NULL);
+ *device = btrfs_find_device(fs_info->fs_devices, devid,
+ NULL, NULL, true);
if (!*device)
ret = -ENOENT;
} else {
@@ -2322,7 +2303,8 @@ static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
BTRFS_UUID_SIZE);
read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
BTRFS_FSID_SIZE);
- device = btrfs_find_device(fs_info, devid, dev_uuid, fs_uuid);
+ device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid,
+ fs_uuid, true);
BUG_ON(!device); /* Logic error */

if (device->fs_devices->seeding) {
@@ -6254,21 +6236,36 @@ blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
return BLK_STS_OK;
}

-struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
- u8 *uuid, u8 *fsid)
+/*
+ * Find a device specified by @devid or @uuid in the list of @fs_devices, or
+ * return NULL.
+ *
+ * If devid and uuid are both specified, the match must be exact, otherwise
+ * only devid is used.
+ *
+ * If @seed is true, traverse through the seed devices.
+ */
+struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
+ u64 devid, u8 *uuid, u8 *fsid,
+ bool seed)
{
struct btrfs_device *device;
- struct btrfs_fs_devices *cur_devices;

- cur_devices = fs_info->fs_devices;
- while (cur_devices) {
+ while (fs_devices) {
if (!fsid ||
- !memcmp(cur_devices->fsid, fsid, BTRFS_FSID_SIZE)) {
- device = find_device(cur_devices, devid, uuid);
- if (device)
- return device;
+ !memcmp(fs_devices->fsid, fsid, BTRFS_FSID_SIZE)) {
+ list_for_each_entry(device, &fs_devices->devices,
+ dev_list) {
+ if (device->devid == devid &&
+ (!uuid || memcmp(device->uuid, uuid,
+ BTRFS_UUID_SIZE) == 0))
+ return device;
+ }
}
- cur_devices = cur_devices->seed;
+ if (seed)
+ fs_devices = fs_devices->seed;
+ else
+ return NULL;
}
return NULL;
}
@@ -6513,8 +6510,8 @@ static int read_one_chunk(struct btrfs_fs_info *fs_info, struct btrfs_key *key,
read_extent_buffer(leaf, uuid, (unsigned long)
btrfs_stripe_dev_uuid_nr(chunk, i),
BTRFS_UUID_SIZE);
- map->stripes[i].dev = btrfs_find_device(fs_info, devid,
- uuid, NULL);
+ map->stripes[i].dev = btrfs_find_device(fs_info->fs_devices,
+ devid, uuid, NULL, true);
if (!map->stripes[i].dev &&
!btrfs_test_opt(fs_info, DEGRADED)) {
free_extent_map(em);
@@ -6653,7 +6650,8 @@ static int read_one_dev(struct btrfs_fs_info *fs_info,
return PTR_ERR(fs_devices);
}

- device = btrfs_find_device(fs_info, devid, dev_uuid, fs_uuid);
+ device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid,
+ fs_uuid, true);
if (!device) {
if (!btrfs_test_opt(fs_info, DEGRADED)) {
btrfs_report_missing_device(fs_info, devid,
@@ -7243,7 +7241,8 @@ int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
int i;

mutex_lock(&fs_devices->device_list_mutex);
- dev = btrfs_find_device(fs_info, stats->devid, NULL, NULL);
+ dev = btrfs_find_device(fs_info->fs_devices, stats->devid,
+ NULL, NULL, true);
mutex_unlock(&fs_devices->device_list_mutex);

if (!dev) {
@@ -7460,7 +7459,7 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
}

/* Make sure no dev extent is beyond device bondary */
- dev = btrfs_find_device(fs_info, devid, NULL, NULL);
+ dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
if (!dev) {
btrfs_err(fs_info, "failed to find devid %llu", devid);
ret = -EUCLEAN;
@@ -7469,7 +7468,8 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,

/* It's possible this device is a dummy for seed device */
if (dev->disk_total_bytes == 0) {
- dev = find_device(fs_info->fs_devices->seed, devid, NULL);
+ dev = btrfs_find_device(fs_info->fs_devices->seed, devid,
+ NULL, NULL, false);
if (!dev) {
btrfs_err(fs_info, "failed to find seed devid %llu",
devid);
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index ac703b15d679..ddd30c162f98 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -430,8 +430,8 @@ void __exit btrfs_cleanup_fs_uuids(void);
int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
int btrfs_grow_device(struct btrfs_trans_handle *trans,
struct btrfs_device *device, u64 new_size);
-struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
- u8 *uuid, u8 *fsid);
+struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
+ u64 devid, u8 *uuid, u8 *fsid, bool seed);
int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
int btrfs_balance(struct btrfs_fs_info *fs_info,
--
2.23.1