target/file: Remove fd_prot bounce buffer

The reason this bounce buffer exists is to allow code
reuse between rd_mcp and fileio in DIF mode. But the fact is,
that this bounce is really not needed at all, we can simply call
sbc_dif_verify on cmd->t_prot_sg and use it for file IO.

This also removes fd_do_prot_rw as fd_do_rw was generalised
to receive file pointer, block size (8 bytes for DIF data) and
total data length.

(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 deec7560f835dca38177ecda6b05f6f9105ba834..fe6c19c1e001caa3e0ef5e4e474ce69e0ce28315 100644 (file)
--- a/drivers/target/target_core_file.c
+++ b/drivers/target/target_core_file.c
@@ -258,75 +258,15 @@ static void fd_free_device(struct se_device *dev)
        kfree(fd_dev);
 }
 
-static int fd_do_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot,
-                        int is_write)
+static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
+                   u32 block_size, struct scatterlist *sgl,
+                   u32 sgl_nents, u32 data_length, int is_write)
 {
-       struct se_device *se_dev = cmd->se_dev;
-       struct fd_dev *dev = FD_DEV(se_dev);
-       struct file *prot_fd = dev->fd_prot_file;
-       loff_t pos = (cmd->t_task_lba * se_dev->prot_length);
-       unsigned char *buf;
-       u32 prot_size;
-       int rc, ret = 1;
-
-       prot_size = (cmd->data_length / se_dev->dev_attrib.block_size) *
-                    se_dev->prot_length;
-
-       if (!is_write) {
-               fd_prot->prot_buf = kzalloc(prot_size, GFP_KERNEL);
-               if (!fd_prot->prot_buf) {
-                       pr_err("Unable to allocate fd_prot->prot_buf\n");
-                       return -ENOMEM;
-               }
-               buf = fd_prot->prot_buf;
-
-               fd_prot->prot_sg_nents = 1;
-               fd_prot->prot_sg = kzalloc(sizeof(struct scatterlist),
-                                          GFP_KERNEL);
-               if (!fd_prot->prot_sg) {
-                       pr_err("Unable to allocate fd_prot->prot_sg\n");
-                       kfree(fd_prot->prot_buf);
-                       return -ENOMEM;
-               }
-               sg_init_table(fd_prot->prot_sg, fd_prot->prot_sg_nents);
-               sg_set_buf(fd_prot->prot_sg, buf, prot_size);
-       }
-
-       if (is_write) {
-               rc = kernel_write(prot_fd, fd_prot->prot_buf, prot_size, pos);
-               if (rc < 0 || prot_size != rc) {
-                       pr_err("kernel_write() for fd_do_prot_rw failed:"
-                              " %d\n", rc);
-                       ret = -EINVAL;
-               }
-       } else {
-               rc = kernel_read(prot_fd, pos, fd_prot->prot_buf, prot_size);
-               if (rc < 0) {
-                       pr_err("kernel_read() for fd_do_prot_rw failed:"
-                              " %d\n", rc);
-                       ret = -EINVAL;
-               }
-       }
-
-       if (is_write || ret < 0) {
-               kfree(fd_prot->prot_sg);
-               kfree(fd_prot->prot_buf);
-       }
-
-       return ret;
-}
-
-static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
-               u32 sgl_nents, int is_write)
-{
-       struct se_device *se_dev = cmd->se_dev;
-       struct fd_dev *dev = FD_DEV(se_dev);
-       struct file *fd = dev->fd_file;
        struct scatterlist *sg;
        struct iov_iter iter;
        struct bio_vec *bvec;
        ssize_t len = 0;
-       loff_t pos = (cmd->t_task_lba * se_dev->dev_attrib.block_size);
+       loff_t pos = (cmd->t_task_lba * block_size);
        int ret = 0, i;
 
        bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
@@ -352,7 +292,7 @@ static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
        kfree(bvec);
 
        if (is_write) {
-               if (ret < 0 || ret != cmd->data_length) {
+               if (ret < 0 || ret != data_length) {
                        pr_err("%s() write returned %d\n", __func__, ret);
                        return (ret < 0 ? ret : -EINVAL);
                }
@@ -363,10 +303,10 @@ static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
                 * block_device.
                 */
                if (S_ISBLK(file_inode(fd)->i_mode)) {
-                       if (ret < 0 || ret != cmd->data_length) {
+                       if (ret < 0 || ret != data_length) {
                                pr_err("%s() returned %d, expecting %u for "
                                                "S_ISBLK\n", __func__, ret,
-                                               cmd->data_length);
+                                               data_length);
                                return (ret < 0 ? ret : -EINVAL);
                        }
                } else {
@@ -612,7 +552,9 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
              enum dma_data_direction data_direction)
 {
        struct se_device *dev = cmd->se_dev;
-       struct fd_prot fd_prot;
+       struct fd_dev *fd_dev = FD_DEV(dev);
+       struct file *file = fd_dev->fd_file;
+       struct file *pfile = fd_dev->fd_prot_file;
        sense_reason_t rc;
        int ret = 0;
        /*
@@ -630,51 +572,39 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
         * physical memory addresses to struct iovec virtual memory.
         */
        if (data_direction == DMA_FROM_DEVICE) {
-               memset(&fd_prot, 0, sizeof(struct fd_prot));
-
                if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
-                       ret = fd_do_prot_rw(cmd, &fd_prot, false);
+                       ret = fd_do_rw(cmd, pfile, dev->prot_length,
+                                      cmd->t_prot_sg, cmd->t_prot_nents,
+                                      cmd->prot_length, 0);
                        if (ret < 0)
                                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
                }
 
-               ret = fd_do_rw(cmd, sgl, sgl_nents, 0);
+               ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
+                              sgl, sgl_nents, cmd->data_length, 0);
 
                if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
-                       u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
+                       u32 sectors = cmd->data_length >>
+                                       ilog2(dev->dev_attrib.block_size);
 
                        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);
+                                           0, cmd->t_prot_sg, 0);
+                       if (rc)
                                return rc;
-                       }
-                       sbc_dif_copy_prot(cmd, sectors, true, fd_prot.prot_sg, 0);
-                       kfree(fd_prot.prot_sg);
-                       kfree(fd_prot.prot_buf);
                }
        } else {
-               memset(&fd_prot, 0, sizeof(struct fd_prot));
-
                if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
-                       u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
-
-                       ret = fd_do_prot_rw(cmd, &fd_prot, false);
-                       if (ret < 0)
-                               return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+                       u32 sectors = cmd->data_length >>
+                                       ilog2(dev->dev_attrib.block_size);
 
                        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);
+                       if (rc)
                                return rc;
-                       }
-                       sbc_dif_copy_prot(cmd, sectors, false, fd_prot.prot_sg, 0);
                }
 
-               ret = fd_do_rw(cmd, sgl, sgl_nents, 1);
+               ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
+                              sgl, sgl_nents, cmd->data_length, 1);
                /*
                 * Perform implicit vfs_fsync_range() for fd_do_writev() ops
                 * for SCSI WRITEs with Forced Unit Access (FUA) set.
@@ -683,7 +613,6 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
                if (ret > 0 &&
                    dev->dev_attrib.emulate_fua_write > 0 &&
                    (cmd->se_cmd_flags & SCF_FUA)) {
-                       struct fd_dev *fd_dev = FD_DEV(dev);
                        loff_t start = cmd->t_task_lba *
                                dev->dev_attrib.block_size;
                        loff_t end;
@@ -697,17 +626,16 @@ 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) {
-                       ret = fd_do_prot_rw(cmd, &fd_prot, true);
+                       ret = fd_do_rw(cmd, pfile, dev->prot_length,
+                                      cmd->t_prot_sg, cmd->t_prot_nents,
+                                      cmd->prot_length, 1);
                        if (ret < 0)
                                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
                }
        }
 
-       if (ret < 0) {
-               kfree(fd_prot.prot_sg);
-               kfree(fd_prot.prot_buf);
+       if (ret < 0)
                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
-       }
 
        if (ret)
                target_complete_cmd(cmd, SAM_STAT_GOOD);

diff --git a/drivers/target/target_core_file.h b/drivers/target/target_core_file.h
index 182cbb2950395efa43630364ba3d3f78aca3f925..068966fce3089527fb7f14dd7bd3aa0fafdd1041 100644 (file)
--- a/drivers/target/target_core_file.h
+++ b/drivers/target/target_core_file.h
@@ -21,12 +21,6 @@
 #define FDBD_HAS_BUFFERED_IO_WCE 0x04
 #define FDBD_FORMAT_UNIT_SIZE  2048
 
-struct fd_prot {
-       unsigned char   *prot_buf;
-       struct scatterlist *prot_sg;
-       u32 prot_sg_nents;
-};
-
 struct fd_dev {
        struct se_device dev;