target: Refactor transport_generic_get_mem to target_alloc_sgl

This patch refactors transport_generic_get_mem() to target_alloc_sgl()
for accepting **sgl, *nents, length and zero_page as function parameters
in order to be used for both se_cmd->t_data_sg + se_cmd->t_bidi_data_sg
allocations.

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
This commit is contained in:
Nicholas Bellinger 2013-08-25 15:44:03 -07:00 committed by Nicholas Bellinger
parent 6457740708
commit 200939940e

View file

@ -67,7 +67,6 @@ struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
static void transport_complete_task_attr(struct se_cmd *cmd);
static void transport_handle_queue_full(struct se_cmd *cmd,
struct se_device *dev);
static int transport_generic_get_mem(struct se_cmd *cmd);
static int transport_put_cmd(struct se_cmd *cmd);
static void target_complete_ok_work(struct work_struct *work);
@ -2092,23 +2091,21 @@ void transport_kunmap_data_sg(struct se_cmd *cmd)
EXPORT_SYMBOL(transport_kunmap_data_sg);
static int
transport_generic_get_mem(struct se_cmd *cmd)
target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
bool zero_page)
{
u32 length = cmd->data_length;
unsigned int nents;
struct scatterlist *sg;
struct page *page;
gfp_t zero_flag;
gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
unsigned int nent;
int i = 0;
nents = DIV_ROUND_UP(length, PAGE_SIZE);
cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
if (!cmd->t_data_sg)
nent = DIV_ROUND_UP(length, PAGE_SIZE);
sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
if (!sg)
return -ENOMEM;
cmd->t_data_nents = nents;
sg_init_table(cmd->t_data_sg, nents);
zero_flag = cmd->se_cmd_flags & SCF_SCSI_DATA_CDB ? 0 : __GFP_ZERO;
sg_init_table(sg, nent);
while (length) {
u32 page_len = min_t(u32, length, PAGE_SIZE);
@ -2116,19 +2113,20 @@ transport_generic_get_mem(struct se_cmd *cmd)
if (!page)
goto out;
sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
sg_set_page(&sg[i], page, page_len, 0);
length -= page_len;
i++;
}
*sgl = sg;
*nents = nent;
return 0;
out:
while (i > 0) {
i--;
__free_page(sg_page(&cmd->t_data_sg[i]));
__free_page(sg_page(&sg[i]));
}
kfree(cmd->t_data_sg);
cmd->t_data_sg = NULL;
kfree(sg);
return -ENOMEM;
}
@ -2149,7 +2147,10 @@ transport_generic_new_cmd(struct se_cmd *cmd)
*/
if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
cmd->data_length) {
ret = transport_generic_get_mem(cmd);
bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
cmd->data_length, zero_flag);
if (ret < 0)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}