scsi: target: core: Change the way target_xcopy_do_work() sets restiction on max I/O

[ Upstream commit 689d94ec208cfdf95101d99319cb4bdc5f55774d ]

To determine how many blocks sends in one command, the minimum value is
selected from the hw_max_sectors of both devices. In target_xcopy_do_work,
hw_max_sectors are used as blocks, not sectors; it also ignores the fact
that sectors can be of different sizes, for example 512 and 4096
bytes. Because of this, a number of blocks can be transmitted that the
device will not be able to accept.

Change the selection of max transmission size into bytes.

Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
Reviewed-by: Dmitriy Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
Link: https://lore.kernel.org/r/20221114102500.88892-4-a.kovaleva@yadro.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Stable-dep-of: 395cee83d02d ("scsi: target: iscsit: Stop/wait on cmds during conn close")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/target/target_core_xcopy.c b/drivers/target/target_core_xcopy.c
index 8713cda..781f88c 100644 (file)
--- a/drivers/target/target_core_xcopy.c
+++ b/drivers/target/target_core_xcopy.c
@@ -582,11 +582,11 @@ static int target_xcopy_read_source(
        struct xcopy_op *xop,
        struct se_device *src_dev,
        sector_t src_lba,
-       u32 src_sectors)
+       u32 src_bytes)
 {
        struct xcopy_pt_cmd xpt_cmd;
        struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
-       u32 length = (src_sectors * src_dev->dev_attrib.block_size);
+       u32 transfer_length_block = src_bytes / src_dev->dev_attrib.block_size;
        int rc;
        unsigned char cdb[16];
        bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
@@ -597,11 +597,11 @@ static int target_xcopy_read_source(
        memset(&cdb[0], 0, 16);
        cdb[0] = READ_16;
        put_unaligned_be64(src_lba, &cdb[2]);
-       put_unaligned_be32(src_sectors, &cdb[10]);
-       pr_debug("XCOPY: Built READ_16: LBA: %llu Sectors: %u Length: %u\n",
-               (unsigned long long)src_lba, src_sectors, length);
+       put_unaligned_be32(transfer_length_block, &cdb[10]);
+       pr_debug("XCOPY: Built READ_16: LBA: %llu Blocks: %u Length: %u\n",
+               (unsigned long long)src_lba, transfer_length_block, src_bytes);
 
-       __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
+       __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, src_bytes,
                          DMA_FROM_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0);
 
        rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, src_dev, &cdb[0],
@@ -627,11 +627,11 @@ static int target_xcopy_write_destination(
        struct xcopy_op *xop,
        struct se_device *dst_dev,
        sector_t dst_lba,
-       u32 dst_sectors)
+       u32 dst_bytes)
 {
        struct xcopy_pt_cmd xpt_cmd;
        struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
-       u32 length = (dst_sectors * dst_dev->dev_attrib.block_size);
+       u32 transfer_length_block = dst_bytes / dst_dev->dev_attrib.block_size;
        int rc;
        unsigned char cdb[16];
        bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
@@ -642,11 +642,11 @@ static int target_xcopy_write_destination(
        memset(&cdb[0], 0, 16);
        cdb[0] = WRITE_16;
        put_unaligned_be64(dst_lba, &cdb[2]);
-       put_unaligned_be32(dst_sectors, &cdb[10]);
-       pr_debug("XCOPY: Built WRITE_16: LBA: %llu Sectors: %u Length: %u\n",
-               (unsigned long long)dst_lba, dst_sectors, length);
+       put_unaligned_be32(transfer_length_block, &cdb[10]);
+       pr_debug("XCOPY: Built WRITE_16: LBA: %llu Blocks: %u Length: %u\n",
+               (unsigned long long)dst_lba, transfer_length_block, dst_bytes);
 
-       __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
+       __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, dst_bytes,
                          DMA_TO_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0);
 
        rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, dst_dev, &cdb[0],
@@ -670,9 +670,10 @@ static void target_xcopy_do_work(struct work_struct *work)
        struct se_cmd *ec_cmd = xop->xop_se_cmd;
        struct se_device *src_dev, *dst_dev;
        sector_t src_lba, dst_lba, end_lba;
-       unsigned int max_sectors;
+       unsigned long long max_bytes, max_bytes_src, max_bytes_dst, max_blocks;
        int rc = 0;
-       unsigned short nolb, max_nolb, copied_nolb = 0;
+       unsigned short nolb;
+       unsigned int copied_bytes = 0;
        sense_reason_t sense_rc;
 
        sense_rc = target_parse_xcopy_cmd(xop);
@@ -691,23 +692,31 @@ static void target_xcopy_do_work(struct work_struct *work)
        nolb = xop->nolb;
        end_lba = src_lba + nolb;
        /*
-        * Break up XCOPY I/O into hw_max_sectors sized I/O based on the
-        * smallest max_sectors between src_dev + dev_dev, or
+        * Break up XCOPY I/O into hw_max_sectors * hw_block_size sized
+        * I/O based on the smallest max_bytes between src_dev + dst_dev
         */
-       max_sectors = min(src_dev->dev_attrib.hw_max_sectors,
-                         dst_dev->dev_attrib.hw_max_sectors);
-       max_sectors = min_t(u32, max_sectors, XCOPY_MAX_SECTORS);
+       max_bytes_src = (unsigned long long) src_dev->dev_attrib.hw_max_sectors *
+                       src_dev->dev_attrib.hw_block_size;
+       max_bytes_dst = (unsigned long long) dst_dev->dev_attrib.hw_max_sectors *
+                       dst_dev->dev_attrib.hw_block_size;
 
-       max_nolb = min_t(u16, max_sectors, ((u16)(~0U)));
+       max_bytes = min_t(u64, max_bytes_src, max_bytes_dst);
+       max_bytes = min_t(u64, max_bytes, XCOPY_MAX_BYTES);
 
-       pr_debug("target_xcopy_do_work: nolb: %hu, max_nolb: %hu end_lba: %llu\n",
-                       nolb, max_nolb, (unsigned long long)end_lba);
-       pr_debug("target_xcopy_do_work: Starting src_lba: %llu, dst_lba: %llu\n",
+       /*
+        * Using shift instead of the division because otherwise GCC
+        * generates __udivdi3 that is missing on i386
+        */
+       max_blocks = max_bytes >> ilog2(src_dev->dev_attrib.block_size);
+
+       pr_debug("%s: nolb: %u, max_blocks: %llu end_lba: %llu\n", __func__,
+                       nolb, max_blocks, (unsigned long long)end_lba);
+       pr_debug("%s: Starting src_lba: %llu, dst_lba: %llu\n", __func__,
                        (unsigned long long)src_lba, (unsigned long long)dst_lba);
 
-       while (src_lba < end_lba) {
-               unsigned short cur_nolb = min(nolb, max_nolb);
-               u32 cur_bytes = cur_nolb * src_dev->dev_attrib.block_size;
+       while (nolb) {
+               u32 cur_bytes = min_t(u64, max_bytes, nolb * src_dev->dev_attrib.block_size);
+               unsigned short cur_nolb = cur_bytes / src_dev->dev_attrib.block_size;
 
                if (cur_bytes != xop->xop_data_bytes) {
                        /*
@@ -724,43 +733,43 @@ static void target_xcopy_do_work(struct work_struct *work)
                        xop->xop_data_bytes = cur_bytes;
                }
 
-               pr_debug("target_xcopy_do_work: Calling read src_dev: %p src_lba: %llu,"
-                       " cur_nolb: %hu\n", src_dev, (unsigned long long)src_lba, cur_nolb);
+               pr_debug("%s: Calling read src_dev: %p src_lba: %llu, cur_nolb: %hu\n",
+                               __func__, src_dev, (unsigned long long)src_lba, cur_nolb);
 
-               rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_nolb);
+               rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_bytes);
                if (rc < 0)
                        goto out;
 
-               src_lba += cur_nolb;
-               pr_debug("target_xcopy_do_work: Incremented READ src_lba to %llu\n",
+               src_lba += cur_bytes / src_dev->dev_attrib.block_size;
+               pr_debug("%s: Incremented READ src_lba to %llu\n", __func__,
                                (unsigned long long)src_lba);
 
-               pr_debug("target_xcopy_do_work: Calling write dst_dev: %p dst_lba: %llu,"
-                       " cur_nolb: %hu\n", dst_dev, (unsigned long long)dst_lba, cur_nolb);
+               pr_debug("%s: Calling write dst_dev: %p dst_lba: %llu, cur_nolb: %u\n",
+                               __func__, dst_dev, (unsigned long long)dst_lba, cur_nolb);
 
                rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
-                                               dst_lba, cur_nolb);
+                                               dst_lba, cur_bytes);
                if (rc < 0)
                        goto out;
 
-               dst_lba += cur_nolb;
-               pr_debug("target_xcopy_do_work: Incremented WRITE dst_lba to %llu\n",
+               dst_lba += cur_bytes / dst_dev->dev_attrib.block_size;
+               pr_debug("%s: Incremented WRITE dst_lba to %llu\n", __func__,
                                (unsigned long long)dst_lba);
 
-               copied_nolb += cur_nolb;
-               nolb -= cur_nolb;
+               copied_bytes += cur_bytes;
+               nolb -= cur_bytes / src_dev->dev_attrib.block_size;
        }
 
        xcopy_pt_undepend_remotedev(xop);
        target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
        kfree(xop);
 
-       pr_debug("target_xcopy_do_work: Final src_lba: %llu, dst_lba: %llu\n",
+       pr_debug("%s: Final src_lba: %llu, dst_lba: %llu\n", __func__,
                (unsigned long long)src_lba, (unsigned long long)dst_lba);
-       pr_debug("target_xcopy_do_work: Blocks copied: %hu, Bytes Copied: %u\n",
-               copied_nolb, copied_nolb * dst_dev->dev_attrib.block_size);
+       pr_debug("%s: Blocks copied: %u, Bytes Copied: %u\n", __func__,
+               copied_bytes / dst_dev->dev_attrib.block_size, copied_bytes);
 
-       pr_debug("target_xcopy_do_work: Setting X-COPY GOOD status -> sending response\n");
+       pr_debug("%s: Setting X-COPY GOOD status -> sending response\n", __func__);
        target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
        return;
 
@@ -776,8 +785,8 @@ out:
 
 err_free:
        kfree(xop);
-       pr_warn_ratelimited("target_xcopy_do_work: rc: %d, sense: %u, XCOPY operation failed\n",
-                          rc, sense_rc);
+       pr_warn_ratelimited("%s: rc: %d, sense: %u, XCOPY operation failed\n",
+                          __func__, rc, sense_rc);
        target_complete_cmd_with_sense(ec_cmd, SAM_STAT_CHECK_CONDITION, sense_rc);
 }
 

diff --git a/drivers/target/target_core_xcopy.h b/drivers/target/target_core_xcopy.h
index e5f2000..0aad7dc 100644 (file)
--- a/drivers/target/target_core_xcopy.h
+++ b/drivers/target/target_core_xcopy.h
@@ -5,7 +5,7 @@
 #define XCOPY_TARGET_DESC_LEN          32
 #define XCOPY_SEGMENT_DESC_LEN         28
 #define XCOPY_NAA_IEEE_REGEX_LEN       16
-#define XCOPY_MAX_SECTORS              4096
+#define XCOPY_MAX_BYTES                        16777216 /* 16 MB */
 
 /*
  * SPC4r37 6.4.6.1