target: Merge sbc_verify_dif_read|write

Instead of providing DIF verify routines for read/write
that are almost identical and conditionally copy protection
information, just let the caller do the right thing.

Have a single sbc_dif_verify that handles an sgl (that
does NOT copy any data) and a protection information copy
routine used by rd_mcp and fileio backend.

In the WRITE case, call sbc_dif_verify with cmd->t_prot_sg
and then do the copy from it to local sgl (assuming the verify
succeeded of course). In the READ case, call sbc_dif_verify
with the local sgl and if it succeeds, copy it to t_prot_sg (or
not if we are stripping it).

(Fix apply breakage from commit c836777 - nab)

Tested-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
index 3f27bfd..deec756 100644 (file)
--- a/drivers/target/target_core_file.c
+++ b/drivers/target/target_core_file.c
@@ -643,13 +643,14 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
                if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
                        u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 
-                       rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors,
-                                                0, fd_prot.prot_sg, 0);
+                       rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
+                                           0, fd_prot.prot_sg, 0);
                        if (rc) {
                                kfree(fd_prot.prot_sg);
                                kfree(fd_prot.prot_buf);
                                return rc;
                        }
+                       sbc_dif_copy_prot(cmd, sectors, true, fd_prot.prot_sg, 0);
                        kfree(fd_prot.prot_sg);
                        kfree(fd_prot.prot_buf);
                }
@@ -663,13 +664,14 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
                        if (ret < 0)
                                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 
-                       rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors,
-                                                 0, fd_prot.prot_sg, 0);
+                       rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
+                                           0, cmd->t_prot_sg, 0);
                        if (rc) {
                                kfree(fd_prot.prot_sg);
                                kfree(fd_prot.prot_buf);
                                return rc;
                        }
+                       sbc_dif_copy_prot(cmd, sectors, false, fd_prot.prot_sg, 0);
                }
 
                ret = fd_do_rw(cmd, sgl, sgl_nents, 1);

diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c
index d16489b..55315fd 100644 (file)
--- a/drivers/target/target_core_rd.c
+++ b/drivers/target/target_core_rd.c
@@ -403,10 +403,7 @@ static struct rd_dev_sg_table *rd_get_prot_table(struct rd_dev *rd_dev, u32 page
        return NULL;
 }
 
-typedef sense_reason_t (*dif_verify)(struct se_cmd *, sector_t, unsigned int,
-                                    unsigned int, struct scatterlist *, int);
-
-static sense_reason_t rd_do_prot_rw(struct se_cmd *cmd, dif_verify dif_verify)
+static sense_reason_t rd_do_prot_rw(struct se_cmd *cmd, bool is_read)
 {
        struct se_device *se_dev = cmd->se_dev;
        struct rd_dev *dev = RD_DEV(se_dev);
@@ -466,7 +463,16 @@ static sense_reason_t rd_do_prot_rw(struct se_cmd *cmd, dif_verify dif_verify)
 
 #endif /* !CONFIG_ARCH_HAS_SG_CHAIN */
 
-       rc = dif_verify(cmd, cmd->t_task_lba, sectors, 0, prot_sg, prot_offset);
+       if (is_read)
+               rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 0,
+                                   prot_sg, prot_offset);
+       else
+               rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 0,
+                                   cmd->t_prot_sg, 0);
+
+       if (!rc)
+               sbc_dif_copy_prot(cmd, sectors, is_read, prot_sg, prot_offset);
+
        if (need_to_release)
                kfree(prot_sg);
 
@@ -512,7 +518,7 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 
        if (cmd->prot_type && se_dev->dev_attrib.pi_prot_type &&
            data_direction == DMA_TO_DEVICE) {
-               rc = rd_do_prot_rw(cmd, sbc_dif_verify_write);
+               rc = rd_do_prot_rw(cmd, false);
                if (rc)
                        return rc;
        }
@@ -580,7 +586,7 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 
        if (cmd->prot_type && se_dev->dev_attrib.pi_prot_type &&
            data_direction == DMA_FROM_DEVICE) {
-               rc = rd_do_prot_rw(cmd, sbc_dif_verify_read);
+               rc = rd_do_prot_rw(cmd, true);
                if (rc)
                        return rc;
        }

diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index 733824e..ca95fab 100644 (file)
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -1266,9 +1266,8 @@ check_ref:
        return 0;
 }
 
-static void
-sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
-                 struct scatterlist *sg, int sg_off)
+void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
+                      struct scatterlist *sg, int sg_off)
 {
        struct se_device *dev = cmd->se_dev;
        struct scatterlist *psg;
@@ -1309,68 +1308,11 @@ sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
                kunmap_atomic(paddr);
        }
 }
+EXPORT_SYMBOL(sbc_dif_copy_prot);
 
 sense_reason_t
-sbc_dif_verify_write(struct se_cmd *cmd, sector_t start, unsigned int sectors,
-                    unsigned int ei_lba, struct scatterlist *sg, int sg_off)
-{
-       struct se_device *dev = cmd->se_dev;
-       struct se_dif_v1_tuple *sdt;
-       struct scatterlist *dsg, *psg = cmd->t_prot_sg;
-       sector_t sector = start;
-       void *daddr, *paddr;
-       int i, j, offset = 0;
-       sense_reason_t rc;
-
-       for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
-               daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
-               paddr = kmap_atomic(sg_page(psg)) + psg->offset;
-
-               for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
-
-                       if (offset >= psg->length) {
-                               kunmap_atomic(paddr);
-                               psg = sg_next(psg);
-                               paddr = kmap_atomic(sg_page(psg)) + psg->offset;
-                               offset = 0;
-                       }
-
-                       sdt = paddr + offset;
-
-                       pr_debug("DIF WRITE sector: %llu guard_tag: 0x%04x"
-                                " app_tag: 0x%04x ref_tag: %u\n",
-                                (unsigned long long)sector, sdt->guard_tag,
-                                sdt->app_tag, be32_to_cpu(sdt->ref_tag));
-
-                       rc = sbc_dif_v1_verify(cmd, sdt, daddr + j, sector,
-                                              ei_lba);
-                       if (rc) {
-                               kunmap_atomic(paddr);
-                               kunmap_atomic(daddr);
-                               cmd->bad_sector = sector;
-                               return rc;
-                       }
-
-                       sector++;
-                       ei_lba++;
-                       offset += sizeof(struct se_dif_v1_tuple);
-               }
-
-               kunmap_atomic(paddr);
-               kunmap_atomic(daddr);
-       }
-       if (!sg)
-               return 0;
-
-       sbc_dif_copy_prot(cmd, sectors, false, sg, sg_off);
-
-       return 0;
-}
-EXPORT_SYMBOL(sbc_dif_verify_write);
-
-static sense_reason_t
-__sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
-                     unsigned int ei_lba, struct scatterlist *sg, int sg_off)
+sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
+              unsigned int ei_lba, struct scatterlist *sg, int sg_off)
 {
        struct se_device *dev = cmd->se_dev;
        struct se_dif_v1_tuple *sdt;
@@ -1426,28 +1368,4 @@ __sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
 
        return 0;
 }
-
-sense_reason_t
-sbc_dif_read_strip(struct se_cmd *cmd)
-{
-       struct se_device *dev = cmd->se_dev;
-       u32 sectors = cmd->prot_length / dev->prot_length;
-
-       return __sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors, 0,
-                                    cmd->t_prot_sg, 0);
-}
-
-sense_reason_t
-sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
-                   unsigned int ei_lba, struct scatterlist *sg, int sg_off)
-{
-       sense_reason_t rc;
-
-       rc = __sbc_dif_verify_read(cmd, start, sectors, ei_lba, sg, sg_off);
-       if (rc)
-               return rc;
-
-       sbc_dif_copy_prot(cmd, sectors, true, sg, sg_off);
-       return 0;
-}
-EXPORT_SYMBOL(sbc_dif_verify_read);
+EXPORT_SYMBOL(sbc_dif_verify);

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 675f2d9..105f4fd 100644 (file)
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -1766,8 +1766,8 @@ static int target_write_prot_action(struct se_cmd *cmd)
                        break;
 
                sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
-               cmd->pi_err = sbc_dif_verify_write(cmd, cmd->t_task_lba,
-                                                  sectors, 0, NULL, 0);
+               cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
+                                            sectors, 0, cmd->t_prot_sg, 0);
                if (unlikely(cmd->pi_err)) {
                        spin_lock_irq(&cmd->t_state_lock);
                        cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
@@ -1991,16 +1991,17 @@ static void transport_handle_queue_full(
 
 static bool target_read_prot_action(struct se_cmd *cmd)
 {
-       sense_reason_t rc;
-
        switch (cmd->prot_op) {
        case TARGET_PROT_DIN_STRIP:
                if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
-                       rc = sbc_dif_read_strip(cmd);
-                       if (rc) {
-                               cmd->pi_err = rc;
+                       u32 sectors = cmd->data_length >>
+                                 ilog2(cmd->se_dev->dev_attrib.block_size);
+
+                       cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
+                                                    sectors, 0, cmd->t_prot_sg,
+                                                    0);
+                       if (cmd->pi_err)
                                return true;
-                       }
                }
                break;
        case TARGET_PROT_DIN_INSERT:

diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h
index 5f12257..47fafec 100644 (file)
--- a/include/target/target_core_backend.h
+++ b/include/target/target_core_backend.h
@@ -84,12 +84,10 @@ sense_reason_t sbc_execute_unmap(struct se_cmd *cmd,
                                      sector_t lba, sector_t nolb),
        void *priv);
 void   sbc_dif_generate(struct se_cmd *);
-sense_reason_t sbc_dif_verify_write(struct se_cmd *, sector_t, unsigned int,
+sense_reason_t sbc_dif_verify(struct se_cmd *, sector_t, unsigned int,
                                     unsigned int, struct scatterlist *, int);
-sense_reason_t sbc_dif_verify_read(struct se_cmd *, sector_t, unsigned int,
-                                   unsigned int, struct scatterlist *, int);
-sense_reason_t sbc_dif_read_strip(struct se_cmd *);
-
+void sbc_dif_copy_prot(struct se_cmd *, unsigned int, bool,
+                      struct scatterlist *, int);
 void   transport_set_vpd_proto_id(struct t10_vpd *, unsigned char *);
 int    transport_set_vpd_assoc(struct t10_vpd *, unsigned char *);
 int    transport_set_vpd_ident_type(struct t10_vpd *, unsigned char *);