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>
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 781859e..607bc3d 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -67,7 +67,6 @@
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 @@
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 @@
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 @@
*/
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;
}