[SCSI] simplify command allocation and freeing a bit

Just have one level of alloc/free functions that take a host instead
of two levels for the allocation and different calling conventions
for the free.

[fengguang.wu@intel.com: docbook problems spotted, now fixed]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Christoph Hellwig 2014-02-20 14:21:00 -08:00 committed by James Bottomley
parent 0f2bb84d2a
commit 7c28334122

View file

@ -161,47 +161,20 @@ static struct scsi_host_cmd_pool scsi_cmd_dma_pool = {
static DEFINE_MUTEX(host_cmd_pool_mutex);
/**
* scsi_pool_alloc_command - internal function to get a fully allocated command
* @pool: slab pool to allocate the command from
* @gfp_mask: mask for the allocation
*
* Returns a fully allocated command (with the allied sense buffer) or
* NULL on failure
*/
static struct scsi_cmnd *
scsi_pool_alloc_command(struct scsi_host_cmd_pool *pool, gfp_t gfp_mask)
{
struct scsi_cmnd *cmd;
cmd = kmem_cache_zalloc(pool->cmd_slab, gfp_mask | pool->gfp_mask);
if (!cmd)
return NULL;
cmd->sense_buffer = kmem_cache_alloc(pool->sense_slab,
gfp_mask | pool->gfp_mask);
if (!cmd->sense_buffer) {
kmem_cache_free(pool->cmd_slab, cmd);
return NULL;
}
return cmd;
}
/**
* scsi_pool_free_command - internal function to release a command
* @pool: slab pool to allocate the command from
* scsi_host_free_command - internal function to release a command
* @shost: host to free the command for
* @cmd: command to release
*
* the command must previously have been allocated by
* scsi_pool_alloc_command.
* scsi_host_alloc_command.
*/
static void
scsi_pool_free_command(struct scsi_host_cmd_pool *pool,
struct scsi_cmnd *cmd)
scsi_host_free_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
{
struct scsi_host_cmd_pool *pool = shost->cmd_pool;
if (cmd->prot_sdb)
kmem_cache_free(scsi_sdb_cache, cmd->prot_sdb);
kmem_cache_free(pool->sense_slab, cmd->sense_buffer);
kmem_cache_free(pool->cmd_slab, cmd);
}
@ -217,22 +190,32 @@ scsi_pool_free_command(struct scsi_host_cmd_pool *pool,
static struct scsi_cmnd *
scsi_host_alloc_command(struct Scsi_Host *shost, gfp_t gfp_mask)
{
struct scsi_host_cmd_pool *pool = shost->cmd_pool;
struct scsi_cmnd *cmd;
cmd = scsi_pool_alloc_command(shost->cmd_pool, gfp_mask);
cmd = kmem_cache_zalloc(pool->cmd_slab, gfp_mask | pool->gfp_mask);
if (!cmd)
return NULL;
goto fail;
cmd->sense_buffer = kmem_cache_alloc(pool->sense_slab,
gfp_mask | pool->gfp_mask);
if (!cmd->sense_buffer)
goto fail_free_cmd;
if (scsi_host_get_prot(shost) >= SHOST_DIX_TYPE0_PROTECTION) {
cmd->prot_sdb = kmem_cache_zalloc(scsi_sdb_cache, gfp_mask);
if (!cmd->prot_sdb) {
scsi_pool_free_command(shost->cmd_pool, cmd);
return NULL;
}
if (!cmd->prot_sdb)
goto fail_free_sense;
}
return cmd;
fail_free_sense:
kmem_cache_free(pool->sense_slab, cmd->sense_buffer);
fail_free_cmd:
kmem_cache_free(pool->cmd_slab, cmd);
fail:
return NULL;
}
/**
@ -320,7 +303,7 @@ void __scsi_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
}
if (likely(cmd != NULL))
scsi_pool_free_command(shost->cmd_pool, cmd);
scsi_host_free_command(shost, cmd);
}
EXPORT_SYMBOL(__scsi_put_command);
@ -456,7 +439,7 @@ void scsi_destroy_command_freelist(struct Scsi_Host *shost)
cmd = list_entry(shost->free_list.next, struct scsi_cmnd, list);
list_del_init(&cmd->list);
scsi_pool_free_command(shost->cmd_pool, cmd);
scsi_host_free_command(shost, cmd);
}
shost->cmd_pool = NULL;
scsi_put_host_cmd_pool(shost->unchecked_isa_dma ? GFP_DMA : GFP_KERNEL);