[PATCH 3/6] block: Create scsi_sense.h for SCSI and ATAPI

Kees Cook
2018-05-22T18:16:40Z

Both SCSI and ATAPI share the sense header. In preparation for using the
struct scsi_sense_hdr more widely, move this into a separate header and
move the helper function to scsi_ioctl.c which is linked with CONFIG_IDE
by way of CONFIG_BLK_SCSI_REQUEST.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
block/scsi_ioctl.c | 64 ++++++++++++++++++++++++++++++++++++++
drivers/scsi/scsi_common.c | 64 --------------------------------------
include/scsi/scsi_cmnd.h | 1 -
include/scsi/scsi_common.h | 32 +------------------
include/scsi/scsi_sense.h | 44 ++++++++++++++++++++++++++
5 files changed, 109 insertions(+), 96 deletions(-)
create mode 100644 include/scsi/scsi_sense.h

diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 60b471f8621b..87ff3cc7a364 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -728,6 +728,70 @@ void scsi_req_init(struct scsi_request *req)
}
EXPORT_SYMBOL(scsi_req_init);

+/**
+ * scsi_normalize_sense - normalize main elements from either fixed or
+ * descriptor sense data format into a common format.
+ *
+ * @sense_buffer: byte array containing sense data returned by device
+ * @sb_len: number of valid bytes in sense_buffer
+ * @sshdr: pointer to instance of structure that common
+ * elements are written to.
+ *
+ * Notes:
+ * The "main elements" from sense data are: response_code, sense_key,
+ * asc, ascq and additional_length (only for descriptor format).
+ *
+ * Typically this function can be called after a device has
+ * responded to a SCSI command with the CHECK_CONDITION status.
+ *
+ * Return value:
+ * true if valid sense data information found, else false;
+ */
+bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
+ struct scsi_sense_hdr *sshdr)
+{
+ memset(sshdr, 0, sizeof(struct scsi_sense_hdr));
+
+ if (!sense_buffer || !sb_len)
+ return false;
+
+ sshdr->response_code = (sense_buffer[0] & 0x7f);
+
+ if (!scsi_sense_valid(sshdr))
+ return false;
+
+ if (sshdr->response_code >= 0x72) {
+ /*
+ * descriptor format
+ */
+ if (sb_len > 1)
+ sshdr->sense_key = (sense_buffer[1] & 0xf);
+ if (sb_len > 2)
+ sshdr->asc = sense_buffer[2];
+ if (sb_len > 3)
+ sshdr->ascq = sense_buffer[3];
+ if (sb_len > 7)
+ sshdr->additional_length = sense_buffer[7];
+ } else {
+ /*
+ * fixed format
+ */
+ if (sb_len > 2)
+ sshdr->sense_key = (sense_buffer[2] & 0xf);
+ if (sb_len > 7) {
+ sb_len = (sb_len < (sense_buffer[7] + 8)) ?
+ sb_len : (sense_buffer[7] + 8);
+ if (sb_len > 12)
+ sshdr->asc = sense_buffer[12];
+ if (sb_len > 13)
+ sshdr->ascq = sense_buffer[13];
+ }
+ }
+
+ return true;
+}
+EXPORT_SYMBOL(scsi_normalize_sense);
+
static int __init blk_scsi_ioctl_init(void)
{
blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
diff --git a/drivers/scsi/scsi_common.c b/drivers/scsi/scsi_common.c
index 90349498f686..8621a07cb967 100644
--- a/drivers/scsi/scsi_common.c
+++ b/drivers/scsi/scsi_common.c
@@ -116,70 +116,6 @@ void int_to_scsilun(u64 lun, struct scsi_lun *scsilun)
}
EXPORT_SYMBOL(int_to_scsilun);

-/**
- * scsi_normalize_sense - normalize main elements from either fixed or
- * descriptor sense data format into a common format.
- *
- * @sense_buffer: byte array containing sense data returned by device
- * @sb_len: number of valid bytes in sense_buffer
- * @sshdr: pointer to instance of structure that common
- * elements are written to.
- *
- * Notes:
- * The "main elements" from sense data are: response_code, sense_key,
- * asc, ascq and additional_length (only for descriptor format).
- *
- * Typically this function can be called after a device has
- * responded to a SCSI command with the CHECK_CONDITION status.
- *
- * Return value:
- * true if valid sense data information found, else false;
- */
-bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
- struct scsi_sense_hdr *sshdr)
-{
- memset(sshdr, 0, sizeof(struct scsi_sense_hdr));
-
- if (!sense_buffer || !sb_len)
- return false;
-
- sshdr->response_code = (sense_buffer[0] & 0x7f);
-
- if (!scsi_sense_valid(sshdr))
- return false;
-
- if (sshdr->response_code >= 0x72) {
- /*
- * descriptor format
- */
- if (sb_len > 1)
- sshdr->sense_key = (sense_buffer[1] & 0xf);
- if (sb_len > 2)
- sshdr->asc = sense_buffer[2];
- if (sb_len > 3)
- sshdr->ascq = sense_buffer[3];
- if (sb_len > 7)
- sshdr->additional_length = sense_buffer[7];
- } else {
- /*
- * fixed format
- */
- if (sb_len > 2)
- sshdr->sense_key = (sense_buffer[2] & 0xf);
- if (sb_len > 7) {
- sb_len = (sb_len < (sense_buffer[7] + 8)) ?
- sb_len : (sense_buffer[7] + 8);
- if (sb_len > 12)
- sshdr->asc = sense_buffer[12];
- if (sb_len > 13)
- sshdr->ascq = sense_buffer[13];
- }
- }
-
- return true;
-}
-EXPORT_SYMBOL(scsi_normalize_sense);
-
/**
* scsi_sense_desc_find - search for a given descriptor type in descriptor sense data format.
* @sense_buffer: byte array of descriptor format sense data
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h
index aaf1e971c6a3..3b9f42f6615c 100644
--- a/include/scsi/scsi_cmnd.h
+++ b/include/scsi/scsi_cmnd.h
@@ -120,7 +120,6 @@ struct scsi_cmnd {
struct request *request; /* The command we are
working on */

-#define SCSI_SENSE_BUFFERSIZE 96
unsigned char *sense_buffer;
/* obtained by REQUEST SENSE when
* CHECK CONDITION is received on original
diff --git a/include/scsi/scsi_common.h b/include/scsi/scsi_common.h
index 731ac09ed231..82d6209f2e10 100644
--- a/include/scsi/scsi_common.h
+++ b/include/scsi/scsi_common.h
@@ -8,6 +8,7 @@

#include <linux/types.h>
#include <scsi/scsi_proto.h>
+#include <scsi/scsi_sense.h>

static inline unsigned
scsi_varlen_cdb_length(const void *hdr)
@@ -31,37 +32,6 @@ extern const char *scsi_device_type(unsigned type);
extern void int_to_scsilun(u64, struct scsi_lun *);
extern u64 scsilun_to_int(struct scsi_lun *);

-/*
- * This is a slightly modified SCSI sense "descriptor" format header.
- * The addition is to allow the 0x70 and 0x71 response codes. The idea
- * is to place the salient data from either "fixed" or "descriptor" sense
- * format into one structure to ease application processing.
- *
- * The original sense buffer should be kept around for those cases
- * in which more information is required (e.g. the LBA of a MEDIUM ERROR).
- */
-struct scsi_sense_hdr { /* See SPC-3 section 4.5 */
- u8 response_code; /* permit: 0x0, 0x70, 0x71, 0x72, 0x73 */
- u8 sense_key;
- u8 asc;
- u8 ascq;
- u8 byte4;
- u8 byte5;
- u8 byte6;
- u8 additional_length; /* always 0 for fixed sense format */
-};
-
-static inline bool scsi_sense_valid(const struct scsi_sense_hdr *sshdr)
-{
- if (!sshdr)
- return false;
-
- return (sshdr->response_code & 0x70) == 0x70;
-}
-
-extern bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
- struct scsi_sense_hdr *sshdr);
-
extern void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq);
int scsi_set_sense_information(u8 *buf, int buf_len, u64 info);
int scsi_set_sense_field_pointer(u8 *buf, int buf_len, u16 fp, u8 bp, bool cd);
diff --git a/include/scsi/scsi_sense.h b/include/scsi/scsi_sense.h
new file mode 100644
index 000000000000..be923c67b93e
--- /dev/null
+++ b/include/scsi/scsi_sense.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Structures and functions used by both SCSI and ATAPI sense code.
+ */
+
+#ifndef _SCSI_SENSE_H_
+#define _SCSI_SENSE_H_
+
+#include <linux/types.h>
+
+/*
+ * This is a slightly modified SCSI sense "descriptor" format header.
+ * The addition is to allow the 0x70 and 0x71 response codes. The idea
+ * is to place the salient data from either "fixed" or "descriptor" sense
+ * format into one structure to ease application processing.
+ *
+ * The original sense buffer should be kept around for those cases
+ * in which more information is required (e.g. the LBA of a MEDIUM ERROR).
+ */
+struct scsi_sense_hdr { /* See SPC-3 section 4.5 */
+ u8 response_code; /* permit: 0x0, 0x70, 0x71, 0x72, 0x73 */
+ u8 sense_key;
+ u8 asc;
+ u8 ascq;
+ u8 byte4;
+ u8 byte5;
+ u8 byte6;
+ u8 additional_length; /* always 0 for fixed sense format */
+};
+
+static inline bool scsi_sense_valid(const struct scsi_sense_hdr *sshdr)
+{
+ if (!sshdr)
+ return false;
+
+ return (sshdr->response_code & 0x70) == 0x70;
+}
+
+#define SCSI_SENSE_BUFFERSIZE 96
+
+extern bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
+ struct scsi_sense_hdr *sshdr);
+
+#endif /* _SCSI_SENSE_H_ */
--
2.17.0