scsi: respect unchecked_isa_dma for blk-mq

Currently blk-mq always allocates the sense buffer using normal GFP_KERNEL
allocation.  Refactor the cmd pool code to split the cmd and sense allocation
and share the code to allocate the sense buffers as well as the sense buffer
slab caches between the legacy and blk-mq path.

Note that this switches to lazy allocation of the sense slab caches - the
slab caches (not the actual allocations) won't be destroy until the scsi
module is unloaded instead of keeping track of hosts using them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 5 insertions, 19 deletions

diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 0f93892f5e2e..469aa0fb6de2 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -100,22 +100,18 @@ EXPORT_SYMBOL(scsi_sd_pm_domain);
 
 struct scsi_host_cmd_pool {
 	struct kmem_cache	*cmd_slab;
-	struct kmem_cache	*sense_slab;
 	unsigned int		users;
 	char			*cmd_name;
-	char			*sense_name;
 	unsigned int		slab_flags;
 };
 
 static struct scsi_host_cmd_pool scsi_cmd_pool = {
 	.cmd_name	= "scsi_cmd_cache",
-	.sense_name	= "scsi_sense_cache",
 	.slab_flags	= SLAB_HWCACHE_ALIGN,
 };
 
 static struct scsi_host_cmd_pool scsi_cmd_dma_pool = {
 	.cmd_name	= "scsi_cmd_cache(DMA)",
-	.sense_name	= "scsi_sense_cache(DMA)",
 	.slab_flags	= SLAB_HWCACHE_ALIGN|SLAB_CACHE_DMA,
 };
 
@@ -136,7 +132,7 @@ scsi_host_free_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
 
 	if (cmd->prot_sdb)
 		kmem_cache_free(scsi_sdb_cache, cmd->prot_sdb);
-	kmem_cache_free(pool->sense_slab, cmd->sense_buffer);
+	scsi_free_sense_buffer(shost, cmd->sense_buffer);
 	kmem_cache_free(pool->cmd_slab, cmd);
 }
 
@@ -158,7 +154,8 @@ scsi_host_alloc_command(struct Scsi_Host *shost, gfp_t gfp_mask)
 	if (!cmd)
 		goto fail;
 
-	cmd->sense_buffer = kmem_cache_alloc(pool->sense_slab, gfp_mask);
+	cmd->sense_buffer = scsi_alloc_sense_buffer(shost, gfp_mask,
+			NUMA_NO_NODE);
 	if (!cmd->sense_buffer)
 		goto fail_free_cmd;
 
@@ -171,7 +168,7 @@ scsi_host_alloc_command(struct Scsi_Host *shost, gfp_t gfp_mask)
 	return cmd;
 
 fail_free_sense:
-	kmem_cache_free(pool->sense_slab, cmd->sense_buffer);
+	scsi_free_sense_buffer(shost, cmd->sense_buffer);
 fail_free_cmd:
 	kmem_cache_free(pool->cmd_slab, cmd);
 fail:
@@ -301,7 +298,6 @@ scsi_find_host_cmd_pool(struct Scsi_Host *shost)
 static void
 scsi_free_host_cmd_pool(struct scsi_host_cmd_pool *pool)
 {
-	kfree(pool->sense_name);
 	kfree(pool->cmd_name);
 	kfree(pool);
 }
@@ -317,8 +313,7 @@ scsi_alloc_host_cmd_pool(struct Scsi_Host *shost)
 		return NULL;
 
 	pool->cmd_name = kasprintf(GFP_KERNEL, "%s_cmd", hostt->proc_name);
-	pool->sense_name = kasprintf(GFP_KERNEL, "%s_sense", hostt->proc_name);
-	if (!pool->cmd_name || !pool->sense_name) {
+	if (!pool->cmd_name) {
 		scsi_free_host_cmd_pool(pool);
 		return NULL;
 	}
@@ -357,12 +352,6 @@ scsi_get_host_cmd_pool(struct Scsi_Host *shost)
 						   pool->slab_flags, NULL);
 		if (!pool->cmd_slab)
 			goto out_free_pool;
-
-		pool->sense_slab = kmem_cache_create(pool->sense_name,
-						     SCSI_SENSE_BUFFERSIZE, 0,
-						     pool->slab_flags, NULL);
-		if (!pool->sense_slab)
-			goto out_free_slab;
 	}
 
 	pool->users++;
@@ -371,8 +360,6 @@ out:
 	mutex_unlock(&host_cmd_pool_mutex);
 	return retval;
 
-out_free_slab:
-	kmem_cache_destroy(pool->cmd_slab);
 out_free_pool:
 	if (hostt->cmd_size) {
 		scsi_free_host_cmd_pool(pool);
@@ -398,7 +385,6 @@ static void scsi_put_host_cmd_pool(struct Scsi_Host *shost)
 
 	if (!--pool->users) {
 		kmem_cache_destroy(pool->cmd_slab);
-		kmem_cache_destroy(pool->sense_slab);
 		if (hostt->cmd_size) {
 			scsi_free_host_cmd_pool(pool);
 			hostt->cmd_pool = NULL;