// SPDX-License-Identifier: GPL-2.0 /* * SCSI functions used by both the initiator and the target code. */ #include #include #include #include #include #include #include MODULE_LICENSE("GPL v2"); /* Command group 3 is reserved and should never be used. */ const unsigned char scsi_command_size_tbl[8] = { 6, 10, 10, 12, 16, 12, 10, 10 }; EXPORT_SYMBOL(scsi_command_size_tbl); /* NB: These are exposed through /proc/scsi/scsi and form part of the ABI. * You may not alter any existing entry (although adding new ones is * encouraged once assigned by ANSI/INCITS T10). */ static const char *const scsi_device_types[] = { "Direct-Access ", "Sequential-Access", "Printer ", "Processor ", "WORM ", "CD-ROM ", "Scanner ", "Optical Device ", "Medium Changer ", "Communications ", "ASC IT8 ", "ASC IT8 ", "RAID ", "Enclosure ", "Direct-Access-RBC", "Optical card ", "Bridge controller", "Object storage ", "Automation/Drive ", "Security Manager ", "Direct-Access-ZBC", }; /** * scsi_device_type - Return 17-char string indicating device type. * @type: type number to look up */ const char *scsi_device_type(unsigned type) { if (type == 0x1e) return "Well-known LUN "; if (type == 0x1f) return "No Device "; if (type >= ARRAY_SIZE(scsi_device_types)) return "Unknown "; return scsi_device_types[type]; } EXPORT_SYMBOL(scsi_device_type); /** * scsilun_to_int - convert a scsi_lun to an int * @scsilun: struct scsi_lun to be converted. * * Description: * Convert @scsilun from a struct scsi_lun to a four-byte host byte-ordered * integer, and return the result. The caller must check for * truncation before using this function. * * Notes: * For a description of the LUN format, post SCSI-3 see the SCSI * Architecture Model, for SCSI-3 see the SCSI Controller Commands. * * Given a struct scsi_lun of: d2 04 0b 03 00 00 00 00, this function * returns the integer: 0x0b03d204 * * This encoding will return a standard integer LUN for LUNs smaller * than 256, which typically use a single level LUN structure with * addressing method 0. */ u64 scsilun_to_int(struct scsi_lun *scsilun) { int i; u64 lun; lun = 0; for (i = 0; i < sizeof(lun); i += 2) lun = lun | (((u64)scsilun->scsi_lun[i] << ((i + 1) * 8)) | ((u64)scsilun->scsi_lun[i + 1] << (i * 8))); return lun; } EXPORT_SYMBOL(scsilun_to_int); /** * int_to_scsilun - reverts an int into a scsi_lun * @lun: integer to be reverted * @scsilun: struct scsi_lun to be set. * * Description: * Reverts the functionality of the scsilun_to_int, which packed * an 8-byte lun value into an int. This routine unpacks the int * back into the lun value. * * Notes: * Given an integer : 0x0b03d204, this function returns a * struct scsi_lun of: d2 04 0b 03 00 00 00 00 * */ void int_to_scsilun(u64 lun, struct scsi_lun *scsilun) { int i; memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun)); for (i = 0; i < sizeof(lun); i += 2) { scsilun->scsi_lun[i] = (lun >> 8) & 0xFF; scsilun->scsi_lun[i+1] = lun & 0xFF; lun = lun >> 16; } } 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 * @sb_len: number of valid bytes in sense_buffer * @desc_type: value of descriptor type to find * (e.g. 0 -> information) * * Notes: * only valid when sense data is in descriptor format * * Return value: * pointer to start of (first) descriptor if found else NULL */ const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len, int desc_type) { int add_sen_len, add_len, desc_len, k; const u8 * descp; if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7]))) return NULL; if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73)) return NULL; add_sen_len = (add_sen_len < (sb_len - 8)) ? add_sen_len : (sb_len - 8); descp = &sense_buffer[8]; for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) { descp += desc_len; add_len = (k < (add_sen_len - 1)) ? descp[1]: -1; desc_len = add_len + 2; if (descp[0] == desc_type) return descp; if (add_len < 0) // short descriptor ?? break; } return NULL; } EXPORT_SYMBOL(scsi_sense_desc_find); /** * scsi_build_sense_buffer - build sense data in a buffer * @desc: Sense format (non-zero == descriptor format, * 0 == fixed format) * @buf: Where to build sense data * @key: Sense key * @asc: Additional sense code * @ascq: Additional sense code qualifier * **/ void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq) { if (desc) { buf[0] = 0x72; /* descriptor, current */ buf[1] = key; buf[2] = asc; buf[3] = ascq; buf[7] = 0; } else { buf[0] = 0x70; /* fixed, current */ buf[2] = key; buf[7] = 0xa; buf[12] = asc; buf[13] = ascq; } } EXPORT_SYMBOL(scsi_build_sense_buffer); /** * scsi_set_sense_information - set the information field in a * formatted sense data buffer * @buf: Where to build sense data * @buf_len: buffer length * @info: 64-bit information value to be set * * Return value: * 0 on success or -EINVAL for invalid sense buffer length **/ int scsi_set_sense_information(u8 *buf, int buf_len, u64 info) { if ((buf[0] & 0x7f) == 0x72) { u8 *ucp, len; len = buf[7]; ucp = (char *)scsi_sense_desc_find(buf, len + 8, 0); if (!ucp) { buf[7] = len + 0xc; ucp = buf + 8 + len; } if (buf_len < len + 0xc) /* Not enough room for info */ return -EINVAL; ucp[0] = 0; ucp[1] = 0xa; ucp[2] = 0x80; /* Valid bit */ ucp[3] = 0; put_unaligned_be64(info, &ucp[4]); } else if ((buf[0] & 0x7f) == 0x70) { /* * Only set the 'VALID' bit if we can represent the value * correctly; otherwise just fill out the lower bytes and * clear the 'VALID' flag. */ if (info <= 0xffffffffUL) buf[0] |= 0x80; else buf[0] &= 0x7f; put_unaligned_be32((u32)info, &buf[3]); } return 0; } EXPORT_SYMBOL(scsi_set_sense_information); /** * scsi_set_sense_field_pointer - set the field pointer sense key * specific information in a formatted sense data buffer * @buf: Where to build sense data * @buf_len: buffer length * @fp: field pointer to be set * @bp: bit pointer to be set * @cd: command/data bit * * Return value: * 0 on success or -EINVAL for invalid sense buffer length */ int scsi_set_sense_field_pointer(u8 *buf, int buf_len, u16 fp, u8 bp, bool cd) { u8 *ucp, len; if ((buf[0] & 0x7f) == 0x72) { len = buf[7]; ucp = (char *)scsi_sense_desc_find(buf, len + 8, 2); if (!ucp) { buf[7] = len + 8; ucp = buf + 8 + len; } if (buf_len < len + 8) /* Not enough room for info */ return -EINVAL; ucp[0] = 2; ucp[1] = 6; ucp[4] = 0x80; /* Valid bit */ if (cd) ucp[4] |= 0x40; if (bp < 0x8) ucp[4] |= 0x8 | bp; put_unaligned_be16(fp, &ucp[5]); } else if ((buf[0] & 0x7f) == 0x70) { len = buf[7]; if (len < 18) buf[7] = 18; buf[15] = 0x80; if (cd) buf[15] |= 0x40; if (bp < 0x8) buf[15] |= 0x8 | bp; put_unaligned_be16(fp, &buf[16]); } return 0; } EXPORT_SYMBOL(scsi_set_sense_field_pointer);