target: move unmap to struct spc_ops

Having all the unmap payload parsing in the backed is a bit ugly, but until
more drivers support it and we can find a good interface for all of them
that seems the way to go.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index ee70cc9..8a12e29 100644 (file)
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -40,6 +40,7 @@
 #include <linux/module.h>
 #include <scsi/scsi.h>
 #include <scsi/scsi_host.h>
+#include <asm/unaligned.h>
 
 #include <target/target_core_base.h>
 #include <target/target_core_backend.h>
@@ -318,13 +319,52 @@ static int iblock_execute_sync_cache(struct se_cmd *cmd)
        return 0;
 }
 
-static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range)
+static int iblock_execute_unmap(struct se_cmd *cmd)
 {
+       struct se_device *dev = cmd->se_dev;
        struct iblock_dev *ibd = dev->dev_ptr;
-       struct block_device *bd = ibd->ibd_bd;
-       int barrier = 0;
+       unsigned char *buf, *ptr = NULL;
+       unsigned char *cdb = &cmd->t_task_cdb[0];
+       sector_t lba;
+       unsigned int size = cmd->data_length, range;
+       int ret = 0, offset;
+       unsigned short dl, bd_dl;
+
+       /* First UNMAP block descriptor starts at 8 byte offset */
+       offset = 8;
+       size -= 8;
+       dl = get_unaligned_be16(&cdb[0]);
+       bd_dl = get_unaligned_be16(&cdb[2]);
+
+       buf = transport_kmap_data_sg(cmd);
+
+       ptr = &buf[offset];
+       pr_debug("UNMAP: Sub: %s Using dl: %hu bd_dl: %hu size: %hu"
+               " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
+
+       while (size) {
+               lba = get_unaligned_be64(&ptr[0]);
+               range = get_unaligned_be32(&ptr[8]);
+               pr_debug("UNMAP: Using lba: %llu and range: %u\n",
+                                (unsigned long long)lba, range);
+
+               ret = blkdev_issue_discard(ibd->ibd_bd, lba, range,
+                                          GFP_KERNEL, 0);
+               if (ret < 0) {
+                       pr_err("blkdev_issue_discard() failed: %d\n",
+                                       ret);
+                       goto err;
+               }
+
+               ptr += 16;
+               size -= 16;
+       }
 
-       return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier);
+err:
+       transport_kunmap_data_sg(cmd);
+       if (!ret)
+               target_complete_cmd(cmd, GOOD);
+       return ret;
 }
 
 static int iblock_execute_write_same(struct se_cmd *cmd)
@@ -687,6 +727,7 @@ static struct spc_ops iblock_spc_ops = {
        .execute_rw             = iblock_execute_rw,
        .execute_sync_cache     = iblock_execute_sync_cache,
        .execute_write_same     = iblock_execute_write_same,
+       .execute_unmap          = iblock_execute_unmap,
 };
 
 static int iblock_parse_cdb(struct se_cmd *cmd)
@@ -706,7 +747,6 @@ static struct se_subsystem_api iblock_template = {
        .create_virtdevice      = iblock_create_virtdevice,
        .free_device            = iblock_free_device,
        .parse_cdb              = iblock_parse_cdb,
-       .do_discard             = iblock_do_discard,
        .check_configfs_dev_params = iblock_check_configfs_dev_params,
        .set_configfs_dev_params = iblock_set_configfs_dev_params,
        .show_configfs_dev_params = iblock_show_configfs_dev_params,

diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index 146ca37..a9dd946 100644 (file)
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -99,63 +99,6 @@ static int sbc_emulate_readcapacity_16(struct se_cmd *cmd)
        return 0;
 }
 
-/*
- * Used for TCM/IBLOCK and TCM/FILEIO for block/blk-lib.c level discard support.
- * Note this is not used for TCM/pSCSI passthrough
- */
-static int sbc_emulate_unmap(struct se_cmd *cmd)
-{
-       struct se_device *dev = cmd->se_dev;
-       unsigned char *buf, *ptr = NULL;
-       unsigned char *cdb = &cmd->t_task_cdb[0];
-       sector_t lba;
-       unsigned int size = cmd->data_length, range;
-       int ret = 0, offset;
-       unsigned short dl, bd_dl;
-
-       if (!dev->transport->do_discard) {
-               pr_err("UNMAP emulation not supported for: %s\n",
-                               dev->transport->name);
-               cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
-               return -ENOSYS;
-       }
-
-       /* First UNMAP block descriptor starts at 8 byte offset */
-       offset = 8;
-       size -= 8;
-       dl = get_unaligned_be16(&cdb[0]);
-       bd_dl = get_unaligned_be16(&cdb[2]);
-
-       buf = transport_kmap_data_sg(cmd);
-
-       ptr = &buf[offset];
-       pr_debug("UNMAP: Sub: %s Using dl: %hu bd_dl: %hu size: %hu"
-               " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
-
-       while (size) {
-               lba = get_unaligned_be64(&ptr[0]);
-               range = get_unaligned_be32(&ptr[8]);
-               pr_debug("UNMAP: Using lba: %llu and range: %u\n",
-                                (unsigned long long)lba, range);
-
-               ret = dev->transport->do_discard(dev, lba, range);
-               if (ret < 0) {
-                       pr_err("blkdev_issue_discard() failed: %d\n",
-                                       ret);
-                       goto err;
-               }
-
-               ptr += 16;
-               size -= 16;
-       }
-
-err:
-       transport_kunmap_data_sg(cmd);
-       if (!ret)
-               target_complete_cmd(cmd, GOOD);
-       return ret;
-}
-
 int spc_get_write_same_sectors(struct se_cmd *cmd)
 {
        u32 num_blocks;
@@ -533,8 +476,11 @@ int sbc_parse_cdb(struct se_cmd *cmd, struct spc_ops *ops)
                cmd->execute_cmd = ops->execute_sync_cache;
                break;
        case UNMAP:
+               if (!ops->execute_unmap)
+                       goto out_unsupported_cdb;
+
                size = get_unaligned_be16(&cdb[7]);
-               cmd->execute_cmd = sbc_emulate_unmap;
+               cmd->execute_cmd = ops->execute_unmap;
                break;
        case WRITE_SAME_16:
                if (!ops->execute_write_same)

diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h
index fbc6a1b..f1405d3 100644 (file)
--- a/include/target/target_core_backend.h
+++ b/include/target/target_core_backend.h
@@ -26,7 +26,6 @@ struct se_subsystem_api {
        int (*transport_complete)(struct se_cmd *cmd, struct scatterlist *);
 
        int (*parse_cdb)(struct se_cmd *cmd);
-       int (*do_discard)(struct se_device *, sector_t, u32);
        ssize_t (*check_configfs_dev_params)(struct se_hba *,
                        struct se_subsystem_dev *);
        ssize_t (*set_configfs_dev_params)(struct se_hba *,
@@ -43,6 +42,7 @@ struct spc_ops {
        int (*execute_rw)(struct se_cmd *cmd);
        int (*execute_sync_cache)(struct se_cmd *cmd);
        int (*execute_write_same)(struct se_cmd *cmd);
+       int (*execute_unmap)(struct se_cmd *cmd);
 };
 
 int    transport_subsystem_register(struct se_subsystem_api *);