Btrfs: Check device uuids along with devids

Signed-off-by: Chris Mason <chris.mason@oracle.com>

2 files changed, 28 insertions, 7 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index b56ae1950658..d119d95d139a 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -800,6 +800,11 @@ static inline struct btrfs_stripe *btrfs_stripe_nr(struct btrfs_chunk *c,
         return (struct btrfs_stripe *)offset;
 }
 
+static inline char *btrfs_stripe_dev_uuid_nr(struct btrfs_chunk *c, int nr)
+{
+        return btrfs_stripe_dev_uuid(btrfs_stripe_nr(c, nr));
+}
+
 static inline u64 btrfs_stripe_offset_nr(struct extent_buffer *eb,
                                          struct btrfs_chunk *c, int nr)
 {
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index c11b6fd408a6..cdf0019cca2e 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -69,15 +69,18 @@ int btrfs_cleanup_fs_uuids(void)
         return 0;
 }
 
-static struct btrfs_device *__find_device(struct list_head *head, u64 devid)
+static 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);
-                if (dev->devid == devid)
+                if (dev->devid == devid &&
+                    !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE)) {
                         return dev;
+                }
         }
         return NULL;
 }
@@ -117,7 +120,8 @@ static int device_list_add(const char *path,
                 fs_devices->num_devices = 0;
                 device = NULL;
         } else {
-                device = __find_device(&fs_devices->devices, devid);
+                device = __find_device(&fs_devices->devices, devid,
+                                       disk_super->dev_item.uuid);
         }
         if (!device) {
                 device = kzalloc(sizeof(*device), GFP_NOFS);
@@ -126,6 +130,8 @@ static int device_list_add(const char *path,
                         return -ENOMEM;
                 }
                 device->devid = devid;
+                memcpy(device->uuid, disk_super->dev_item.uuid,
+                       BTRFS_UUID_SIZE);
                 device->barriers = 1;
                 spin_lock_init(&device->io_lock);
                 device->name = kstrdup(path, GFP_NOFS);
@@ -1098,11 +1104,12 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
         return 0;
 }
 
-struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid)
+struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
+                                       u8 *uuid)
 {
         struct list_head *head = &root->fs_info->fs_devices->devices;
 
-        return __find_device(head, devid);
+        return __find_device(head, devid, uuid);
 }
 
 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
@@ -1115,6 +1122,7 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
         u64 logical;
         u64 length;
         u64 devid;
+        u8 uuid[BTRFS_UUID_SIZE];
         int num_stripes;
         int ret;
         int i;
@@ -1163,7 +1171,10 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
                 map->stripes[i].physical =
                         btrfs_stripe_offset_nr(leaf, chunk, i);
                 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
-                map->stripes[i].dev = btrfs_find_device(root, 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(root, devid, uuid);
                 if (!map->stripes[i].dev) {
                         kfree(map);
                         free_extent_map(em);
@@ -1207,8 +1218,13 @@ static int read_one_dev(struct btrfs_root *root,
         struct btrfs_device *device;
         u64 devid;
         int ret;
+        u8 dev_uuid[BTRFS_UUID_SIZE];
+
         devid = btrfs_device_id(leaf, dev_item);
-        device = btrfs_find_device(root, devid);
+        read_extent_buffer(leaf, dev_uuid,
+                           (unsigned long)btrfs_device_uuid(dev_item),
+                           BTRFS_UUID_SIZE);
+        device = btrfs_find_device(root, devid, dev_uuid);
         if (!device) {
                 printk("warning devid %Lu not found already\n", devid);
                 device = kzalloc(sizeof(*device), GFP_NOFS);