From f68d98b21fa74155dc7c1fd212474379ac3c7531 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Mon, 27 Nov 2017 13:27:41 +0100 Subject: [PATCH] scsi: provide general-purpose functions to manage sense data Extract the common parts of scsi_sense_buf_to_errno, scsi_convert_sense and scsi_target_send_command's REQUEST SENSE handling into two new functions scsi_parse_sense_buf and scsi_build_sense_buf. Fix a bug in scsi_target_send_command along the way; the length was written in buf[10] rather than buf[7]. Reported-by: Dr. David Alan Gilbert Reviewed-by: Dr. David Alan Gilbert Fixes: b07fbce634 ("scsi-bus: correct responses for INQUIRY and REQUEST SENSE") Signed-off-by: Paolo Bonzini --- hw/scsi/scsi-bus.c | 16 +---- include/scsi/utils.h | 3 + scsi/utils.c | 139 +++++++++++++++++++++---------------------- 3 files changed, 72 insertions(+), 86 deletions(-) diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c index 977f7bce1f..965becf31f 100644 --- a/hw/scsi/scsi-bus.c +++ b/hw/scsi/scsi-bus.c @@ -540,20 +540,8 @@ static int32_t scsi_target_send_command(SCSIRequest *req, uint8_t *buf) if (req->lun != 0) { const struct SCSISense sense = SENSE_CODE(LUN_NOT_SUPPORTED); - if (fixed_sense) { - r->buf[0] = 0x70; - r->buf[2] = sense.key; - r->buf[10] = 10; - r->buf[12] = sense.asc; - r->buf[13] = sense.ascq; - r->len = MIN(req->cmd.xfer, SCSI_SENSE_LEN); - } else { - r->buf[0] = 0x72; - r->buf[1] = sense.key; - r->buf[2] = sense.asc; - r->buf[3] = sense.ascq; - r->len = 8; - } + r->len = scsi_build_sense_buf(r->buf, req->cmd.xfer, + sense, fixed_sense); } else { r->len = scsi_device_get_sense(r->req.dev, r->buf, MIN(req->cmd.xfer, r->buf_len), diff --git a/include/scsi/utils.h b/include/scsi/utils.h index eb07e474ee..4b705f5e0f 100644 --- a/include/scsi/utils.h +++ b/include/scsi/utils.h @@ -31,6 +31,9 @@ typedef struct SCSISense { } SCSISense; int scsi_build_sense(uint8_t *buf, SCSISense sense); +SCSISense scsi_parse_sense_buf(const uint8_t *in_buf, int in_len); +int scsi_build_sense_buf(uint8_t *buf, size_t max_size, SCSISense sense, + bool fixed_sense); /* * Predefined sense codes diff --git a/scsi/utils.c b/scsi/utils.c index e4182a9b09..61bc1a8e2b 100644 --- a/scsi/utils.c +++ b/scsi/utils.c @@ -96,15 +96,60 @@ int scsi_cdb_length(uint8_t *buf) return cdb_len; } +SCSISense scsi_parse_sense_buf(const uint8_t *in_buf, int in_len) +{ + bool fixed_in; + SCSISense sense; + + assert(in_len > 0); + fixed_in = (in_buf[0] & 2) == 0; + if (fixed_in) { + if (in_len < 14) { + return SENSE_CODE(IO_ERROR); + } + sense.key = in_buf[2]; + sense.asc = in_buf[12]; + sense.ascq = in_buf[13]; + } else { + if (in_len < 4) { + return SENSE_CODE(IO_ERROR); + } + sense.key = in_buf[1]; + sense.asc = in_buf[2]; + sense.ascq = in_buf[3]; + } + + return sense; +} + +int scsi_build_sense_buf(uint8_t *out_buf, size_t size, SCSISense sense, + bool fixed_sense) +{ + int len; + uint8_t buf[SCSI_SENSE_LEN] = { 0 }; + + if (fixed_sense) { + buf[0] = 0x70; + buf[2] = sense.key; + buf[7] = 10; + buf[12] = sense.asc; + buf[13] = sense.ascq; + len = 18; + } else { + buf[0] = 0x72; + buf[1] = sense.key; + buf[2] = sense.asc; + buf[3] = sense.ascq; + len = 8; + } + len = MIN(len, size); + memcpy(out_buf, buf, len); + return len; +} + int scsi_build_sense(uint8_t *buf, SCSISense sense) { - memset(buf, 0, 18); - buf[0] = 0x70; - buf[2] = sense.key; - buf[7] = 10; - buf[12] = sense.asc; - buf[13] = sense.ascq; - return 18; + return scsi_build_sense_buf(buf, SCSI_SENSE_LEN, sense, true); } /* @@ -274,52 +319,21 @@ const struct SCSISense sense_code_SPACE_ALLOC_FAILED = { int scsi_convert_sense(uint8_t *in_buf, int in_len, uint8_t *buf, int len, bool fixed) { - bool fixed_in; SCSISense sense; - if (!fixed && len < 8) { - return 0; + bool fixed_in; + + fixed_in = (in_buf[0] & 2) == 0; + if (in_len && fixed == fixed_in) { + memcpy(buf, in_buf, MIN(len, in_len)); + return MIN(len, in_len); } if (in_len == 0) { - sense.key = NO_SENSE; - sense.asc = 0; - sense.ascq = 0; + sense = SENSE_CODE(NO_SENSE); } else { - fixed_in = (in_buf[0] & 2) == 0; - - if (fixed == fixed_in) { - memcpy(buf, in_buf, MIN(len, in_len)); - return MIN(len, in_len); - } - - if (fixed_in) { - sense.key = in_buf[2]; - sense.asc = in_buf[12]; - sense.ascq = in_buf[13]; - } else { - sense.key = in_buf[1]; - sense.asc = in_buf[2]; - sense.ascq = in_buf[3]; - } - } - - memset(buf, 0, len); - if (fixed) { - /* Return fixed format sense buffer */ - buf[0] = 0x70; - buf[2] = sense.key; - buf[7] = 10; - buf[12] = sense.asc; - buf[13] = sense.ascq; - return MIN(len, SCSI_SENSE_LEN); - } else { - /* Return descriptor format sense buffer */ - buf[0] = 0x72; - buf[1] = sense.key; - buf[2] = sense.asc; - buf[3] = sense.ascq; - return 8; + sense = scsi_parse_sense_buf(in_buf, in_len); } + return scsi_build_sense_buf(buf, len, sense, fixed); } int scsi_sense_to_errno(int key, int asc, int ascq) @@ -366,34 +380,15 @@ int scsi_sense_to_errno(int key, int asc, int ascq) } } -int scsi_sense_buf_to_errno(const uint8_t *sense, size_t sense_size) +int scsi_sense_buf_to_errno(const uint8_t *in_buf, size_t in_len) { - int key, asc, ascq; - if (sense_size < 1) { + SCSISense sense; + if (in_len < 1) { return EIO; } - switch (sense[0]) { - case 0x70: /* Fixed format sense data. */ - if (sense_size < 14) { - return EIO; - } - key = sense[2] & 0xF; - asc = sense[12]; - ascq = sense[13]; - break; - case 0x72: /* Descriptor format sense data. */ - if (sense_size < 4) { - return EIO; - } - key = sense[1] & 0xF; - asc = sense[2]; - ascq = sense[3]; - break; - default: - return EIO; - break; - } - return scsi_sense_to_errno(key, asc, ascq); + + sense = scsi_parse_sense_buf(in_buf, in_len); + return scsi_sense_to_errno(sense.key, sense.asc, sense.ascq); } const char *scsi_command_name(uint8_t cmd)