Re: [PATCH 1/6] btrfs: index check-integrity state hash by a dev_t

[Liu Bo]

On Wed, Aug 23, 2017 at 07:10:27PM +0200, Christoph Hellwig wrote:
> We won't have the struct block_device available in the bio soon, so switch
> to the numerical dev_t instead of the block_device pointer for looking up
> the check-integrity state.

Reviewed-by: Liu Bo 

Thanks,

-liubo

> 
> Signed-off-by: Christoph Hellwig 
> ---
>  fs/btrfs/check-integrity.c | 31 +--
>  1 file changed, 13 insertions(+), 18 deletions(-)
> 
> diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
> index 11d37c94ce05..9d3854839038 100644
> --- a/fs/btrfs/check-integrity.c
> +++ b/fs/btrfs/check-integrity.c
> @@ -296,8 +296,7 @@ static void btrfsic_dev_state_hashtable_add(
>   struct btrfsic_dev_state *ds,
>   struct btrfsic_dev_state_hashtable *h);
>  static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds);
> -static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
> - struct block_device *bdev,
> +static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t 
> dev,
>   struct btrfsic_dev_state_hashtable *h);
>  static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void);
>  static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf);
> @@ -385,8 +384,7 @@ static int btrfsic_process_superblock_dev_mirror(
>   int superblock_mirror_num,
>   struct btrfsic_dev_state **selected_dev_state,
>   struct btrfs_super_block *selected_super);
> -static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
> - struct block_device *bdev);
> +static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev);
>  static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
>  u64 bytenr,
>  struct btrfsic_dev_state *dev_state,
> @@ -626,17 +624,15 @@ static void btrfsic_dev_state_hashtable_remove(struct 
> btrfsic_dev_state *ds)
>   list_del(>collision_resolving_node);
>  }
>  
> -static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
> - struct block_device *bdev,
> +static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t 
> dev,
>   struct btrfsic_dev_state_hashtable *h)
>  {
>   const unsigned int hashval =
> - (((unsigned int)((uintptr_t)bdev)) &
> -  (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
> + dev & (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1);
>   struct btrfsic_dev_state *ds;
>  
>   list_for_each_entry(ds, h->table + hashval, collision_resolving_node) {
> - if (ds->bdev == bdev)
> + if (ds->bdev->bd_dev == dev)
>   return ds;
>   }
>  
> @@ -668,7 +664,7 @@ static int btrfsic_process_superblock(struct 
> btrfsic_state *state,
>   if (!device->bdev || !device->name)
>   continue;
>  
> - dev_state = btrfsic_dev_state_lookup(device->bdev);
> + dev_state = btrfsic_dev_state_lookup(device->bdev->bd_dev);
>   BUG_ON(NULL == dev_state);
>   for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
>   ret = btrfsic_process_superblock_dev_mirror(
> @@ -1556,7 +1552,7 @@ static int btrfsic_map_block(struct btrfsic_state 
> *state, u64 bytenr, u32 len,
>   }
>  
>   device = multi->stripes[0].dev;
> - block_ctx_out->dev = btrfsic_dev_state_lookup(device->bdev);
> + block_ctx_out->dev = btrfsic_dev_state_lookup(device->bdev->bd_dev);
>   block_ctx_out->dev_bytenr = multi->stripes[0].physical;
>   block_ctx_out->start = bytenr;
>   block_ctx_out->len = len;
> @@ -2654,7 +2650,7 @@ static struct btrfsic_block 
> *btrfsic_block_lookup_or_add(
>   pr_info("btrfsic: error, kmalloc failed!\n");
>   return NULL;
>   }
> - dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev);
> + dev_state = 
> btrfsic_dev_state_lookup(block_ctx->dev->bdev->bd_dev);
>   if (NULL == dev_state) {
>   pr_info("btrfsic: error, lookup dev_state failed!\n");
>   btrfsic_block_free(block);
> @@ -2734,10 +2730,9 @@ static void btrfsic_cmp_log_and_dev_bytenr(struct 
> btrfsic_state *state,
>   }
>  }
>  
> -static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
> - struct block_device *bdev)
> +static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev)
>  {
> - return btrfsic_dev_state_hashtable_lookup(bdev,
> + return btrfsic_dev_state_hashtable_lookup(dev,
> _dev_state_hashtable);
>  }
>  
> @@ -2751,7 +2746,7 @@ int btrfsic_submit_bh(int op, int op_flags, struct 
> buffer_head *bh)
>   mutex_lock(_mutex);
>   /* since btrfsic_submit_bh() might also be called before
>   

[PATCH 1/6] btrfs: index check-integrity state hash by a dev_t

[Christoph Hellwig]

We won't have the struct block_device available in the bio soon, so switch
to the numerical dev_t instead of the block_device pointer for looking up
the check-integrity state.

Signed-off-by: Christoph Hellwig 
---
 fs/btrfs/check-integrity.c | 31 +--
 1 file changed, 13 insertions(+), 18 deletions(-)

diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index 11d37c94ce05..9d3854839038 100644
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -296,8 +296,7 @@ static void btrfsic_dev_state_hashtable_add(
struct btrfsic_dev_state *ds,
struct btrfsic_dev_state_hashtable *h);
 static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds);
-static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
-   struct block_device *bdev,
+static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t dev,
struct btrfsic_dev_state_hashtable *h);
 static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void);
 static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf);
@@ -385,8 +384,7 @@ static int btrfsic_process_superblock_dev_mirror(
int superblock_mirror_num,
struct btrfsic_dev_state **selected_dev_state,
struct btrfs_super_block *selected_super);
-static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
-   struct block_device *bdev);
+static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev);
 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
   u64 bytenr,
   struct btrfsic_dev_state *dev_state,
@@ -626,17 +624,15 @@ static void btrfsic_dev_state_hashtable_remove(struct 
btrfsic_dev_state *ds)
list_del(>collision_resolving_node);
 }
 
-static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
-   struct block_device *bdev,
+static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t dev,
struct btrfsic_dev_state_hashtable *h)
 {
const unsigned int hashval =
-   (((unsigned int)((uintptr_t)bdev)) &
-(BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
+   dev & (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1);
struct btrfsic_dev_state *ds;
 
list_for_each_entry(ds, h->table + hashval, collision_resolving_node) {
-   if (ds->bdev == bdev)
+   if (ds->bdev->bd_dev == dev)
return ds;
}
 
@@ -668,7 +664,7 @@ static int btrfsic_process_superblock(struct btrfsic_state 
*state,
if (!device->bdev || !device->name)
continue;
 
-   dev_state = btrfsic_dev_state_lookup(device->bdev);
+   dev_state = btrfsic_dev_state_lookup(device->bdev->bd_dev);
BUG_ON(NULL == dev_state);
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
ret = btrfsic_process_superblock_dev_mirror(
@@ -1556,7 +1552,7 @@ static int btrfsic_map_block(struct btrfsic_state *state, 
u64 bytenr, u32 len,
}
 
device = multi->stripes[0].dev;
-   block_ctx_out->dev = btrfsic_dev_state_lookup(device->bdev);
+   block_ctx_out->dev = btrfsic_dev_state_lookup(device->bdev->bd_dev);
block_ctx_out->dev_bytenr = multi->stripes[0].physical;
block_ctx_out->start = bytenr;
block_ctx_out->len = len;
@@ -2654,7 +2650,7 @@ static struct btrfsic_block *btrfsic_block_lookup_or_add(
pr_info("btrfsic: error, kmalloc failed!\n");
return NULL;
}
-   dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev);
+   dev_state = 
btrfsic_dev_state_lookup(block_ctx->dev->bdev->bd_dev);
if (NULL == dev_state) {
pr_info("btrfsic: error, lookup dev_state failed!\n");
btrfsic_block_free(block);
@@ -2734,10 +2730,9 @@ static void btrfsic_cmp_log_and_dev_bytenr(struct 
btrfsic_state *state,
}
 }
 
-static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
-   struct block_device *bdev)
+static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev)
 {
-   return btrfsic_dev_state_hashtable_lookup(bdev,
+   return btrfsic_dev_state_hashtable_lookup(dev,
  _dev_state_hashtable);
 }
 
@@ -2751,7 +2746,7 @@ int btrfsic_submit_bh(int op, int op_flags, struct 
buffer_head *bh)
mutex_lock(_mutex);
/* since btrfsic_submit_bh() might also be called before
 * btrfsic_mount(), this might return NULL */
-   dev_state = btrfsic_dev_state_lookup(bh->b_bdev);
+   dev_state = btrfsic_dev_state_lookup(bh->b_bdev->bd_dev);
 
/* Only called to write the superblock (incl.