diff options
Diffstat (limited to 'drivers/target/target_core_sbc.c')
| -rw-r--r-- | drivers/target/target_core_sbc.c | 36 |
1 files changed, 26 insertions, 10 deletions
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index 22d0cbba6ff3..f7c527a826fd 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -435,13 +435,13 @@ static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success, } /* - * compare @cmp_len bytes of @read_sgl with @cmp_sgl. On miscompare return - * TCM_MISCOMPARE_VERIFY. + * compare @cmp_len bytes of @read_sgl with @cmp_sgl. On miscompare, fill + * @miscmp_off and return TCM_MISCOMPARE_VERIFY. */ static sense_reason_t compare_and_write_do_cmp(struct scatterlist *read_sgl, unsigned int read_nents, struct scatterlist *cmp_sgl, unsigned int cmp_nents, - unsigned int cmp_len) + unsigned int cmp_len, unsigned int *miscmp_off) { unsigned char *buf = NULL; struct scatterlist *sg; @@ -466,18 +466,24 @@ compare_and_write_do_cmp(struct scatterlist *read_sgl, unsigned int read_nents, * Compare SCSI READ payload against verify payload */ offset = 0; + ret = TCM_NO_SENSE; for_each_sg(read_sgl, sg, read_nents, i) { unsigned int len = min(sg->length, cmp_len); unsigned char *addr = kmap_atomic(sg_page(sg)); if (memcmp(addr, buf + offset, len)) { - pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n", - addr, buf + offset); - kunmap_atomic(addr); + unsigned int i; + + for (i = 0; i < len && addr[i] == buf[offset + i]; i++) + ; + *miscmp_off = offset + i; + pr_warn("Detected MISCOMPARE at offset %u\n", + *miscmp_off); ret = TCM_MISCOMPARE_VERIFY; - goto out; } kunmap_atomic(addr); + if (ret != TCM_NO_SENSE) + goto out; offset += len; cmp_len -= len; @@ -485,7 +491,6 @@ compare_and_write_do_cmp(struct scatterlist *read_sgl, unsigned int read_nents, break; } pr_debug("COMPARE AND WRITE read data matches compare data\n"); - ret = TCM_NO_SENSE; out: kfree(buf); return ret; @@ -501,6 +506,7 @@ static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool succes unsigned int len; unsigned int block_size = dev->dev_attrib.block_size; unsigned int compare_len = (cmd->t_task_nolb * block_size); + unsigned int miscmp_off = 0; sense_reason_t ret = TCM_NO_SENSE; int i; @@ -532,8 +538,18 @@ static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool succes cmd->t_bidi_data_nents, cmd->t_data_sg, cmd->t_data_nents, - compare_len); - if (ret) + compare_len, + &miscmp_off); + if (ret == TCM_MISCOMPARE_VERIFY) { + /* + * SBC-4 r15: 5.3 COMPARE AND WRITE command + * In the sense data (see 4.18 and SPC-5) the offset from the + * start of the Data-Out Buffer to the first byte of data that + * was not equal shall be reported in the INFORMATION field. + */ + cmd->sense_info = miscmp_off; + goto out; + } else if (ret) goto out; if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) { |