Prev: 2.6.35-rc2 regression
Next: checkpatch.pl issues in patch
From: FUJITA Tomonori on 7 Jun 2010 02:50
On Sun, 6 Jun 2010 20:50:32 -0700
"Nicholas A. Bellinger" <nab(a)linux-iscsi.org> wrote:

> From: Nicholas Bellinger <nab(a)linux-iscsi.org>
>
> This patch adds struct device_type_template sg_template to usr/bs_sg.c used for STGT LUN
> passthrough with the new bs_sg_lu_init() and bs_sg_rw() functions following usr/sbc.c code
> for TYPE_DISK, but should work for any device type.
>
> It also adds struct bs_sg_init() that is called from existing usr/target.c:tgt_device_create()
> code via struct backingstore_template->bs_init() in order to setup the passthrough specific
> queue and completion handlers for struct scsi_lu->cmd_perform() and ->cmd_done().
>
> Signed-off-by: Nicholas A. Bellinger <nab(a)linux-iscsi.org>
> ---
> usr/bs_sg.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 files changed, 69 insertions(+), 0 deletions(-)
>
> diff --git a/usr/bs_sg.c b/usr/bs_sg.c
> index 8baa480..23676ef 100644
> --- a/usr/bs_sg.c
> +++ b/usr/bs_sg.c
> @@ -38,9 +38,12 @@
> #include "util.h"
> #include "tgtd.h"
> #include "scsi.h"
> +#include "spc.h"
> +#include "tgtadm_error.h"
>
> #define BS_SG_RESVD_SZ (512 * 1024)
> #define BS_SG_TIMEOUT 2000
> +#define BS_SG_SHIFT 9
>
> static int graceful_read(int fd, void *p_read, int to_read)
> {
> @@ -82,6 +85,32 @@ static int graceful_write(int fd, void *p_write, int to_write)
> return 0;
> }
>
> +static int bs_sg_rw(int host_no, struct scsi_cmd *cmd)
> +{
> + int ret;
> + unsigned char key = ILLEGAL_REQUEST;
> + uint16_t asc = ASC_LUN_NOT_SUPPORTED;
> +
> + cmd->scsi_cmd_done = target_cmd_io_done;
> +
> + cmd->offset = (scsi_rw_offset(cmd->scb) << BS_SG_SHIFT);

No need for passthough, I think.


> + ret = cmd->dev->bst->bs_cmd_submit(cmd);
> + if (ret) {
> + key = HARDWARE_ERROR;
> + asc = ASC_INTERNAL_TGT_FAILURE;
> + } else {
> + set_cmd_mmapio(cmd);

This is wrong since this code doesn't mmap io. We can just remove
this.


> + return SAM_STAT_GOOD;
> + }
> +
> + cmd->offset = 0;
> + scsi_set_in_resid_by_actual(cmd, 0);
> + scsi_set_out_resid_by_actual(cmd, 0);
> +
> + sense_data_build(cmd, key, asc);
> + return SAM_STAT_CHECK_CONDITION;
> +}
> +
> static void set_cmd_failed(struct scsi_cmd *cmd)
> {
> int result = SAM_STAT_CHECK_CONDITION;
> @@ -192,6 +221,25 @@ static int init_sg_device(int fd)
> return 0;
> }
>
> +static int bs_sg_init(struct scsi_lu *lu)
> +{
> + /*
> + * Setup struct scsi_lu->cmd_perform() passthrough pointer
> + * (if available) for the underlying device type.
> + */
> + lu->cmd_perform = &target_cmd_perform_passthrough;
> + if (!(lu->cmd_perform)) {
> + eprintf("Unable to locate lu->cmd_perform() for bs_sg\n");
> + return -1;
> + }
> + /*
> + * Setup struct scsi_lu->cmd_done() passthrough pointer using
> + * usr/target.c:__cmd_done_passthrough().
> + */
> + lu->cmd_done = &__cmd_done_passthrough;
> + return 0;
> +}
> +
> static int bs_sg_open(struct scsi_lu *lu, char *path, int *fd, uint64_t *size)
> {
> int sg_fd, err;
> @@ -235,16 +283,37 @@ static int bs_sg_cmd_done(struct scsi_cmd *cmd)
> return 0;
> }
>
> +static int bs_sg_lu_init(struct scsi_lu *lu)
> +{
> + if (spc_lu_init(lu))
> + return TGTADM_NOMEM;
> +
> + return 0;
> +}
> +
> static struct backingstore_template sg_bst = {
> .bs_name = "sg",
> .bs_datasize = 0,
> + .bs_passthrough = 1,
> + .bs_init = bs_sg_init,
> .bs_open = bs_sg_open,
> .bs_close = bs_sg_close,
> .bs_cmd_submit = bs_sg_cmd_submit,
> .bs_cmd_done = bs_sg_cmd_done,
> };
>
> +static struct device_type_template sg_template = {
> + .type = 0,

Let's create a new type to simplify things (e.g. we can avoid adding
sg_bst->bs_passthrough).
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
 | 
Pages: 1
Prev: 2.6.35-rc2 regression
Next: checkpatch.pl issues in patch