target: Add sbc_execute_unmap() helper

iblock_execute_unmap() and fd_execute_unmap share a lot of code.
Add sbc_execute_unmap() helper to remove duplicated code for
iblock_execute_unmap() and fd_execute_unmap().

Cc: Christoph Hellwig <hch@lst.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

3 files changed, 93 insertions, 155 deletions

diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
index d5b84fac31c7..9063c31df9e1 100644
--- a/drivers/target/target_core_file.c
+++ b/drivers/target/target_core_file.c
@@ -480,8 +480,9 @@ fd_execute_write_same(struct se_cmd *cmd)
 }
 
 static sense_reason_t
-fd_do_unmap(struct se_cmd *cmd, struct file *file, sector_t lba, sector_t nolb)
+fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
 {
+        struct file *file = priv;
         struct inode *inode = file->f_mapping->host;
         int ret;
 
@@ -542,84 +543,9 @@ fd_execute_write_same_unmap(struct se_cmd *cmd)
 static sense_reason_t
 fd_execute_unmap(struct se_cmd *cmd)
 {
-        struct se_device *dev = cmd->se_dev;
-        struct fd_dev *fd_dev = FD_DEV(dev);
-        struct file *file = fd_dev->fd_file;
-        unsigned char *buf, *ptr = NULL;
-        sector_t lba;
-        int size;
-        u32 range;
-        sense_reason_t ret = 0;
-        int dl, bd_dl;
-
-        /* We never set ANC_SUP */
-        if (cmd->t_task_cdb[1])
-                return TCM_INVALID_CDB_FIELD;
-
-        if (cmd->data_length == 0) {
-                target_complete_cmd(cmd, SAM_STAT_GOOD);
-                return 0;
-        }
-
-        if (cmd->data_length < 8) {
-                pr_warn("UNMAP parameter list length %u too small\n",
-                        cmd->data_length);
-                return TCM_PARAMETER_LIST_LENGTH_ERROR;
-        }
-
-        buf = transport_kmap_data_sg(cmd);
-        if (!buf)
-                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
-
-        dl = get_unaligned_be16(&buf[0]);
-        bd_dl = get_unaligned_be16(&buf[2]);
+        struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 
-        size = cmd->data_length - 8;
-        if (bd_dl > size)
-                pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
-                        cmd->data_length, bd_dl);
-        else
-                size = bd_dl;
-
-        if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
-                ret = TCM_INVALID_PARAMETER_LIST;
-                goto err;
-        }
-
-        /* First UNMAP block descriptor starts at 8 byte offset */
-        ptr = &buf[8];
-        pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
-                " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
-
-        while (size >= 16) {
-                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);
-
-                if (range > dev->dev_attrib.max_unmap_lba_count) {
-                        ret = TCM_INVALID_PARAMETER_LIST;
-                        goto err;
-                }
-
-                if (lba + range > dev->transport->get_blocks(dev) + 1) {
-                        ret = TCM_ADDRESS_OUT_OF_RANGE;
-                        goto err;
-                }
-
-                ret = fd_do_unmap(cmd, file, lba, range);
-                if (ret)
-                        goto err;
-
-                ptr += 16;
-                size -= 16;
-        }
-
-err:
-        transport_kunmap_data_sg(cmd);
-        if (!ret)
-                target_complete_cmd(cmd, GOOD);
-        return ret;
+        return sbc_execute_unmap(cmd, fd_do_unmap, file);
 }
 
 static sense_reason_t
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 96a9b620e89a..07f5f94634bb 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -380,9 +380,10 @@ iblock_execute_sync_cache(struct se_cmd *cmd)
 }
 
 static sense_reason_t
-iblock_do_unmap(struct se_cmd *cmd, struct block_device *bdev,
+iblock_do_unmap(struct se_cmd *cmd, void *priv,
                 sector_t lba, sector_t nolb)
 {
+        struct block_device *bdev = priv;
         int ret;
 
         ret = blkdev_issue_discard(bdev, lba, nolb, GFP_KERNEL, 0);
@@ -397,83 +398,9 @@ iblock_do_unmap(struct se_cmd *cmd, struct block_device *bdev,
 static sense_reason_t
 iblock_execute_unmap(struct se_cmd *cmd)
 {
-        struct se_device *dev = cmd->se_dev;
-        struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
-        unsigned char *buf, *ptr = NULL;
-        sector_t lba;
-        int size;
-        u32 range;
-        sense_reason_t ret = 0;
-        int dl, bd_dl;
-
-        /* We never set ANC_SUP */
-        if (cmd->t_task_cdb[1])
-                return TCM_INVALID_CDB_FIELD;
-
-        if (cmd->data_length == 0) {
-                target_complete_cmd(cmd, SAM_STAT_GOOD);
-                return 0;
-        }
-
-        if (cmd->data_length < 8) {
-                pr_warn("UNMAP parameter list length %u too small\n",
-                        cmd->data_length);
-                return TCM_PARAMETER_LIST_LENGTH_ERROR;
-        }
-
-        buf = transport_kmap_data_sg(cmd);
-        if (!buf)
-                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
-
-        dl = get_unaligned_be16(&buf[0]);
-        bd_dl = get_unaligned_be16(&buf[2]);
-
-        size = cmd->data_length - 8;
-        if (bd_dl > size)
-                pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
-                        cmd->data_length, bd_dl);
-        else
-                size = bd_dl;
-
-        if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
-                ret = TCM_INVALID_PARAMETER_LIST;
-                goto err;
-        }
-
-        /* First UNMAP block descriptor starts at 8 byte offset */
-        ptr = &buf[8];
-        pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
-                " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
-
-        while (size >= 16) {
-                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);
-
-                if (range > dev->dev_attrib.max_unmap_lba_count) {
-                        ret = TCM_INVALID_PARAMETER_LIST;
-                        goto err;
-                }
-
-                if (lba + range > dev->transport->get_blocks(dev) + 1) {
-                        ret = TCM_ADDRESS_OUT_OF_RANGE;
-                        goto err;
-                }
-
-                ret = iblock_do_unmap(cmd, ib_dev->ibd_bd, lba, range);
-                if (ret)
-                        goto err;
-
-                ptr += 16;
-                size -= 16;
-        }
+        struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
 
-err:
-        transport_kunmap_data_sg(cmd);
-        if (!ret)
-                target_complete_cmd(cmd, GOOD);
-        return ret;
+        return sbc_execute_unmap(cmd, iblock_do_unmap, bdev);
 }
 
 static sense_reason_t
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index 60d4b5185f32..bbc5b0ee2bdc 100644
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -596,3 +596,88 @@ u32 sbc_get_device_type(struct se_device *dev)
         return TYPE_DISK;
 }
 EXPORT_SYMBOL(sbc_get_device_type);
+
+sense_reason_t
+sbc_execute_unmap(struct se_cmd *cmd,
+        sense_reason_t (*do_unmap_fn)(struct se_cmd *, void *,
+                                      sector_t, sector_t),
+        void *priv)
+{
+        struct se_device *dev = cmd->se_dev;
+        unsigned char *buf, *ptr = NULL;
+        sector_t lba;
+        int size;
+        u32 range;
+        sense_reason_t ret = 0;
+        int dl, bd_dl;
+
+        /* We never set ANC_SUP */
+        if (cmd->t_task_cdb[1])
+                return TCM_INVALID_CDB_FIELD;
+
+        if (cmd->data_length == 0) {
+                target_complete_cmd(cmd, SAM_STAT_GOOD);
+                return 0;
+        }
+
+        if (cmd->data_length < 8) {
+                pr_warn("UNMAP parameter list length %u too small\n",
+                        cmd->data_length);
+                return TCM_PARAMETER_LIST_LENGTH_ERROR;
+        }
+
+        buf = transport_kmap_data_sg(cmd);
+        if (!buf)
+                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+        dl = get_unaligned_be16(&buf[0]);
+        bd_dl = get_unaligned_be16(&buf[2]);
+
+        size = cmd->data_length - 8;
+        if (bd_dl > size)
+                pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
+                        cmd->data_length, bd_dl);
+        else
+                size = bd_dl;
+
+        if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
+                ret = TCM_INVALID_PARAMETER_LIST;
+                goto err;
+        }
+
+        /* First UNMAP block descriptor starts at 8 byte offset */
+        ptr = &buf[8];
+        pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
+                " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
+
+        while (size >= 16) {
+                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);
+
+                if (range > dev->dev_attrib.max_unmap_lba_count) {
+                        ret = TCM_INVALID_PARAMETER_LIST;
+                        goto err;
+                }
+
+                if (lba + range > dev->transport->get_blocks(dev) + 1) {
+                        ret = TCM_ADDRESS_OUT_OF_RANGE;
+                        goto err;
+                }
+
+                ret = do_unmap_fn(cmd, priv, lba, range);
+                if (ret)
+                        goto err;
+
+                ptr += 16;
+                size -= 16;
+        }
+
+err:
+        transport_kunmap_data_sg(cmd);
+        if (!ret)
+                target_complete_cmd(cmd, GOOD);
+        return ret;
+}
+EXPORT_SYMBOL(sbc_execute_unmap);