btrfs: handle device lookup with btrfs_dev_lookup_args

We have a lot of device lookup functions that all do something slightly
different.  Clean this up by adding a struct to hold the different
lookup criteria, and then pass this around to btrfs_find_device() so it
can do the proper matching based on the lookup criteria.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 76 insertions, 46 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 918ad3790791..eddd2e50cb65 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -812,9 +812,13 @@ static noinline struct btrfs_device *device_list_add(const char *path,
 
 		device = NULL;
 	} else {
+		struct btrfs_dev_lookup_args args = {
+			.devid = devid,
+			.uuid = disk_super->dev_item.uuid,
+		};
+
 		mutex_lock(&fs_devices->device_list_mutex);
-		device = btrfs_find_device(fs_devices, devid,
-				disk_super->dev_item.uuid, NULL);
+		device = btrfs_find_device(fs_devices, &args);
 
 		/*
 		 * If this disk has been pulled into an fs devices created by
@@ -2324,10 +2328,9 @@ void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev)
 static struct btrfs_device *btrfs_find_device_by_path(
 		struct btrfs_fs_info *fs_info, const char *device_path)
 {
+	BTRFS_DEV_LOOKUP_ARGS(args);
 	int ret = 0;
 	struct btrfs_super_block *disk_super;
-	u64 devid;
-	u8 *dev_uuid;
 	struct block_device *bdev;
 	struct btrfs_device *device;
 
@@ -2336,14 +2339,14 @@ static struct btrfs_device *btrfs_find_device_by_path(
 	if (ret)
 		return ERR_PTR(ret);
 
-	devid = btrfs_stack_device_id(&disk_super->dev_item);
-	dev_uuid = disk_super->dev_item.uuid;
+	args.devid = btrfs_stack_device_id(&disk_super->dev_item);
+	args.uuid = disk_super->dev_item.uuid;
 	if (btrfs_fs_incompat(fs_info, METADATA_UUID))
-		device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid,
-					   disk_super->metadata_uuid);
+		args.fsid = disk_super->metadata_uuid;
 	else
-		device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid,
-					   disk_super->fsid);
+		args.fsid = disk_super->fsid;
+
+	device = btrfs_find_device(fs_info->fs_devices, &args);
 
 	btrfs_release_disk_super(disk_super);
 	if (!device)
@@ -2359,11 +2362,12 @@ struct btrfs_device *btrfs_find_device_by_devspec(
 		struct btrfs_fs_info *fs_info, u64 devid,
 		const char *device_path)
 {
+	BTRFS_DEV_LOOKUP_ARGS(args);
 	struct btrfs_device *device;
 
 	if (devid) {
-		device = btrfs_find_device(fs_info->fs_devices, devid, NULL,
-					   NULL);
+		args.devid = devid;
+		device = btrfs_find_device(fs_info->fs_devices, &args);
 		if (!device)
 			return ERR_PTR(-ENOENT);
 		return device;
@@ -2373,14 +2377,11 @@ struct btrfs_device *btrfs_find_device_by_devspec(
 		return ERR_PTR(-EINVAL);
 
 	if (strcmp(device_path, "missing") == 0) {
-		/* Find first missing device */
-		list_for_each_entry(device, &fs_info->fs_devices->devices,
-				    dev_list) {
-			if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
-				     &device->dev_state) && !device->bdev)
-				return device;
-		}
-		return ERR_PTR(-ENOENT);
+		args.missing = true;
+		device = btrfs_find_device(fs_info->fs_devices, &args);
+		if (!device)
+			return ERR_PTR(-ENOENT);
+		return device;
 	}
 
 	return btrfs_find_device_by_path(fs_info, device_path);
@@ -2460,6 +2461,7 @@ static int btrfs_prepare_sprout(struct btrfs_fs_info *fs_info)
  */
 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans)
 {
+	BTRFS_DEV_LOOKUP_ARGS(args);
 	struct btrfs_fs_info *fs_info = trans->fs_info;
 	struct btrfs_root *root = fs_info->chunk_root;
 	struct btrfs_path *path;
@@ -2469,7 +2471,6 @@ static int btrfs_finish_sprout(struct btrfs_trans_handle *trans)
 	struct btrfs_key key;
 	u8 fs_uuid[BTRFS_FSID_SIZE];
 	u8 dev_uuid[BTRFS_UUID_SIZE];
-	u64 devid;
 	int ret;
 
 	path = btrfs_alloc_path();
@@ -2506,13 +2507,14 @@ next_slot:
 
 		dev_item = btrfs_item_ptr(leaf, path->slots[0],
 					  struct btrfs_dev_item);
-		devid = btrfs_device_id(leaf, dev_item);
+		args.devid = btrfs_device_id(leaf, dev_item);
 		read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
 				   BTRFS_UUID_SIZE);
 		read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
 				   BTRFS_FSID_SIZE);
-		device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid,
-					   fs_uuid);
+		args.uuid = dev_uuid;
+		args.fsid = fs_uuid;
+		device = btrfs_find_device(fs_info->fs_devices, &args);
 		BUG_ON(!device); /* Logic error */
 
 		if (device->fs_devices->seeding) {
@@ -6754,6 +6756,33 @@ blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 	return BLK_STS_OK;
 }
 
+static bool dev_args_match_fs_devices(const struct btrfs_dev_lookup_args *args,
+				      const struct btrfs_fs_devices *fs_devices)
+{
+	if (args->fsid == NULL)
+		return true;
+	if (memcmp(fs_devices->metadata_uuid, args->fsid, BTRFS_FSID_SIZE) == 0)
+		return true;
+	return false;
+}
+
+static bool dev_args_match_device(const struct btrfs_dev_lookup_args *args,
+				  const struct btrfs_device *device)
+{
+	ASSERT((args->devid != (u64)-1) || args->missing);
+
+	if ((args->devid != (u64)-1) && device->devid != args->devid)
+		return false;
+	if (args->uuid && memcmp(device->uuid, args->uuid, BTRFS_UUID_SIZE) != 0)
+		return false;
+	if (!args->missing)
+		return true;
+	if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state) &&
+	    !device->bdev)
+		return true;
+	return false;
+}
+
 /*
  * Find a device specified by @devid or @uuid in the list of @fs_devices, or
  * return NULL.
@@ -6761,31 +6790,25 @@ blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
  * If devid and uuid are both specified, the match must be exact, otherwise
  * only devid is used.
  */
-struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
-				       u64 devid, u8 *uuid, u8 *fsid)
+struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
+				       const struct btrfs_dev_lookup_args *args)
 {
 	struct btrfs_device *device;
 	struct btrfs_fs_devices *seed_devs;
 
-	if (!fsid || !memcmp(fs_devices->metadata_uuid, fsid, BTRFS_FSID_SIZE)) {
+	if (dev_args_match_fs_devices(args, fs_devices)) {
 		list_for_each_entry(device, &fs_devices->devices, dev_list) {
-			if (device->devid == devid &&
-			    (!uuid || memcmp(device->uuid, uuid,
-					     BTRFS_UUID_SIZE) == 0))
+			if (dev_args_match_device(args, device))
 				return device;
 		}
 	}
 
 	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
-		if (!fsid ||
-		    !memcmp(seed_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE)) {
-			list_for_each_entry(device, &seed_devs->devices,
-					    dev_list) {
-				if (device->devid == devid &&
-				    (!uuid || memcmp(device->uuid, uuid,
-						     BTRFS_UUID_SIZE) == 0))
-					return device;
-			}
+		if (!dev_args_match_fs_devices(args, seed_devs))
+			continue;
+		list_for_each_entry(device, &seed_devs->devices, dev_list) {
+			if (dev_args_match_device(args, device))
+				return device;
 		}
 	}
 
@@ -6951,6 +6974,7 @@ static void warn_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
 static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
 			  struct btrfs_chunk *chunk)
 {
+	BTRFS_DEV_LOOKUP_ARGS(args);
 	struct btrfs_fs_info *fs_info = leaf->fs_info;
 	struct extent_map_tree *map_tree = &fs_info->mapping_tree;
 	struct map_lookup *map;
@@ -7028,11 +7052,12 @@ static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
 		map->stripes[i].physical =
 			btrfs_stripe_offset_nr(leaf, chunk, i);
 		devid = btrfs_stripe_devid_nr(leaf, chunk, i);
+		args.devid = devid;
 		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->fs_devices,
-							devid, uuid, NULL);
+		args.uuid = uuid;
+		map->stripes[i].dev = btrfs_find_device(fs_info->fs_devices, &args);
 		if (!map->stripes[i].dev &&
 		    !btrfs_test_opt(fs_info, DEGRADED)) {
 			free_extent_map(em);
@@ -7150,6 +7175,7 @@ static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info,
 static int read_one_dev(struct extent_buffer *leaf,
 			struct btrfs_dev_item *dev_item)
 {
+	BTRFS_DEV_LOOKUP_ARGS(args);
 	struct btrfs_fs_info *fs_info = leaf->fs_info;
 	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 	struct btrfs_device *device;
@@ -7158,11 +7184,13 @@ static int read_one_dev(struct extent_buffer *leaf,
 	u8 fs_uuid[BTRFS_FSID_SIZE];
 	u8 dev_uuid[BTRFS_UUID_SIZE];
 
-	devid = btrfs_device_id(leaf, dev_item);
+	devid = args.devid = btrfs_device_id(leaf, dev_item);
 	read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
 			   BTRFS_UUID_SIZE);
 	read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
 			   BTRFS_FSID_SIZE);
+	args.uuid = dev_uuid;
+	args.fsid = fs_uuid;
 
 	if (memcmp(fs_uuid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE)) {
 		fs_devices = open_seed_devices(fs_info, fs_uuid);
@@ -7170,8 +7198,7 @@ static int read_one_dev(struct extent_buffer *leaf,
 			return PTR_ERR(fs_devices);
 	}
 
-	device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid,
-				   fs_uuid);
+	device = btrfs_find_device(fs_info->fs_devices, &args);
 	if (!device) {
 		if (!btrfs_test_opt(fs_info, DEGRADED)) {
 			btrfs_report_missing_device(fs_info, devid,
@@ -7840,12 +7867,14 @@ static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
 			struct btrfs_ioctl_get_dev_stats *stats)
 {
+	BTRFS_DEV_LOOKUP_ARGS(args);
 	struct btrfs_device *dev;
 	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 	int i;
 
 	mutex_lock(&fs_devices->device_list_mutex);
-	dev = btrfs_find_device(fs_info->fs_devices, stats->devid, NULL, NULL);
+	args.devid = stats->devid;
+	dev = btrfs_find_device(fs_info->fs_devices, &args);
 	mutex_unlock(&fs_devices->device_list_mutex);
 
 	if (!dev) {
@@ -7921,6 +7950,7 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
 				 u64 chunk_offset, u64 devid,
 				 u64 physical_offset, u64 physical_len)
 {
+	struct btrfs_dev_lookup_args args = { .devid = devid };
 	struct extent_map_tree *em_tree = &fs_info->mapping_tree;
 	struct extent_map *em;
 	struct map_lookup *map;
@@ -7976,7 +8006,7 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
 	}
 
 	/* Make sure no dev extent is beyond device boundary */
-	dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL);
+	dev = btrfs_find_device(fs_info->fs_devices, &args);
 	if (!dev) {
 		btrfs_err(fs_info, "failed to find devid %llu", devid);
 		ret = -EUCLEAN;