From: David Zeuthen Date: Sat, 30 Oct 2010 15:44:06 +0000 (-0400) Subject: ata_id: Support SG_IO version 4 interface X-Git-Tag: 174~310 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6992637e3165d433353c996aad16c8d141b00845;p=systemd ata_id: Support SG_IO version 4 interface This makes it possible to use /dev/bsg/* nodes for ata_id: # /lib/udev/ata_id --export /dev/bsg/0\:0\:0\:0 ID_ATA=1 ID_TYPE=disk ID_BUS=ata ID_MODEL=INTEL_SSDSA2MH080G1GC ID_MODEL_ENC=INTEL\x20SSDSA2MH080G1GC\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20 ID_REVISION=045C8802 [...] This means that our cd-rom detection as per commit http://git.kernel.org/?p=linux/hotplug/udev.git;a=commit;h=160b069c25690bfb0c785994c7c3710289179107 needs to be reworked since we can't just use the CDROM_GET_CAPABILITY ioctl on a /dev/bsg node (which is a character device). We do this by just sending the SCSI INQUIRY command and checking the type (CD-ROM's are all type 0x05 and disks are type 0x00) before we issue the ATA IDENTIFY command through the SCSI command ATA PASS_THROUGH (12). (Yes, it's a bit perverse how we have to tunnel our ATA commands through a SCSI command but that's how Linux currently work.) We still support for SG_IO version 3 (we fail back if version 4 fails with EINVAL) because testing reveals that some drivers (such as mpt2sas) still only support version 3 on the block nodes. Signed-off-by: David Zeuthen --- diff --git a/extras/ata_id/ata_id.c b/extras/ata_id/ata_id.c index bf1debe0..41544e92 100644 --- a/extras/ata_id/ata_id.c +++ b/extras/ata_id/ata_id.c @@ -3,7 +3,7 @@ * * Copyright (C) 2005-2008 Kay Sievers * Copyright (C) 2009 Lennart Poettering - * Copyright (C) 2009 David Zeuthen + * Copyright (C) 2009-2010 David Zeuthen * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -39,85 +39,166 @@ #include #include #include +#include #include #include "libudev.h" #include "libudev-private.h" -#define COMMAND_TIMEOUT 2000 +#define COMMAND_TIMEOUT_MSEC (30 * 1000) -/* Sends a SCSI command block */ -static int sg_io(int fd, int direction, - const void *cdb, size_t cdb_len, - void *data, size_t data_len, - void *sense, size_t sense_len) +static int disk_scsi_inquiry_command(int fd, + void *buf, + size_t buf_len) { + struct sg_io_v4 io_v4; + uint8_t cdb[12]; + uint8_t sense[32]; + int ret; - struct sg_io_hdr io_hdr; - - memset(&io_hdr, 0, sizeof(struct sg_io_hdr)); - io_hdr.interface_id = 'S'; - io_hdr.cmdp = (unsigned char*) cdb; - io_hdr.cmd_len = cdb_len; - io_hdr.dxferp = data; - io_hdr.dxfer_len = data_len; - io_hdr.sbp = sense; - io_hdr.mx_sb_len = sense_len; - io_hdr.dxfer_direction = direction; - io_hdr.timeout = COMMAND_TIMEOUT; - return ioctl(fd, SG_IO, &io_hdr); + /* + * INQUIRY, see SPC-4 section 6.4 + */ + memset(cdb, 0, sizeof(cdb)); + cdb[0] = 0x12; /* OPERATION CODE: INQUIRY */ + cdb[3] = (buf_len >> 8); /* ALLOCATION LENGTH */ + cdb[4] = (buf_len & 0xff); + + memset(sense, 0, sizeof(sense)); + + memset(&io_v4, 0, sizeof(struct sg_io_v4)); + io_v4.guard = 'Q'; + io_v4.protocol = BSG_PROTOCOL_SCSI; + io_v4.subprotocol = BSG_SUB_PROTOCOL_SCSI_CMD; + io_v4.request_len = sizeof (cdb); + io_v4.request = (uintptr_t) cdb; + io_v4.max_response_len = sizeof (sense); + io_v4.response = (uintptr_t) sense; + io_v4.din_xfer_len = buf_len; + io_v4.din_xferp = (uintptr_t) buf; + io_v4.timeout = COMMAND_TIMEOUT_MSEC; + + ret = ioctl(fd, SG_IO, &io_v4); + if (ret != 0) { + /* could be that the driver doesn't do version 4, try version 3 */ + if (errno == EINVAL) { + struct sg_io_hdr io_hdr; + + memset(&io_hdr, 0, sizeof(struct sg_io_hdr)); + io_hdr.interface_id = 'S'; + io_hdr.cmdp = (unsigned char*) cdb; + io_hdr.cmd_len = sizeof (cdb); + io_hdr.dxferp = buf; + io_hdr.dxfer_len = buf_len; + io_hdr.sbp = sense; + io_hdr.mx_sb_len = sizeof (sense); + io_hdr.dxfer_direction = SG_DXFER_FROM_DEV; + io_hdr.timeout = COMMAND_TIMEOUT_MSEC; + + ret = ioctl(fd, SG_IO, &io_hdr); + if (ret != 0) + goto out; + + /* even if the ioctl succeeds, we need to check the return value */ + if (!(io_hdr.status == 0 && + io_hdr.host_status == 0 && + io_hdr.driver_status == 0)) { + errno = EIO; + ret = -1; + goto out; + } + } else { + goto out; + } + } + + /* even if the ioctl succeeds, we need to check the return value */ + if (!(io_v4.device_status == 0 && + io_v4.transport_status == 0 && + io_v4.driver_status == 0)) { + errno = EIO; + ret = -1; + goto out; + } + + out: + return ret; } -static int disk_command(int fd, int command, int direction, void *cmd_data, - void *data, size_t *len) +static int disk_identify_command(int fd, + void *buf, + size_t buf_len) { - uint8_t *bytes = cmd_data; + struct sg_io_v4 io_v4; uint8_t cdb[12]; uint8_t sense[32]; uint8_t *desc = sense+8; int ret; /* - * ATA Pass-Through 12 byte command, as described in "T10 04-262r8 - * ATA Command Pass-Through": - * http://www.t10.org/ftp/t10/document.04/04-262r8.pdf + * ATA Pass-Through 12 byte command, as described in + * + * T10 04-262r8 ATA Command Pass-Through + * + * from http://www.t10.org/ftp/t10/document.04/04-262r8.pdf */ memset(cdb, 0, sizeof(cdb)); - cdb[0] = 0xa1; /* OPERATION CODE: 12 byte pass through */ - if (direction == SG_DXFER_NONE) { - cdb[1] = 3 << 1; /* PROTOCOL: Non-Data */ - cdb[2] = 0x20; /* OFF_LINE=0, CK_COND=1, T_DIR=0, BYT_BLOK=0, T_LENGTH=0 */ - } else if (direction == SG_DXFER_FROM_DEV) { - cdb[1] = 4 << 1; /* PROTOCOL: PIO Data-in */ - cdb[2] = 0x2e; /* OFF_LINE=0, CK_COND=1, T_DIR=1, BYT_BLOK=1, T_LENGTH=2 */ - } else if (direction == SG_DXFER_TO_DEV) { - cdb[1] = 5 << 1; /* PROTOCOL: PIO Data-Out */ - cdb[2] = 0x26; /* OFF_LINE=0, CK_COND=1, T_DIR=0, BYT_BLOK=1, T_LENGTH=2 */ - } - cdb[3] = bytes[1]; /* FEATURES */ - cdb[4] = bytes[3]; /* SECTORS */ - cdb[5] = bytes[9]; /* LBA LOW */ - cdb[6] = bytes[8]; /* LBA MID */ - cdb[7] = bytes[7]; /* LBA HIGH */ - cdb[8] = bytes[10] & 0x4F; /* SELECT */ - cdb[9] = (uint8_t) command; + cdb[0] = 0xa1; /* OPERATION CODE: 12 byte pass through */ + cdb[1] = 4 << 1; /* PROTOCOL: PIO Data-in */ + cdb[2] = 0x2e; /* OFF_LINE=0, CK_COND=1, T_DIR=1, BYT_BLOK=1, T_LENGTH=2 */ + cdb[3] = 0; /* FEATURES */ + cdb[4] = 1; /* SECTORS */ + cdb[5] = 0; /* LBA LOW */ + cdb[6] = 0; /* LBA MID */ + cdb[7] = 0; /* LBA HIGH */ + cdb[8] = 0 & 0x4F; /* SELECT */ + cdb[9] = 0xEC; /* Command: ATA IDENTIFY DEVICE */; memset(sense, 0, sizeof(sense)); - if ((ret = sg_io(fd, direction, cdb, sizeof(cdb), data, len ? *len : 0, sense, sizeof(sense))) < 0) - return ret; - if (sense[0] != 0x72 || desc[0] != 0x9 || desc[1] != 0x0c) { + + memset(&io_v4, 0, sizeof(struct sg_io_v4)); + io_v4.guard = 'Q'; + io_v4.protocol = BSG_PROTOCOL_SCSI; + io_v4.subprotocol = BSG_SUB_PROTOCOL_SCSI_CMD; + io_v4.request_len = sizeof (cdb); + io_v4.request = (uintptr_t) cdb; + io_v4.max_response_len = sizeof (sense); + io_v4.response = (uintptr_t) sense; + io_v4.din_xfer_len = buf_len; + io_v4.din_xferp = (uintptr_t) buf; + io_v4.timeout = COMMAND_TIMEOUT_MSEC; + + ret = ioctl(fd, SG_IO, &io_v4); + if (ret != 0) { + /* could be that the driver doesn't do version 4, try version 3 */ + if (errno == EINVAL) { + struct sg_io_hdr io_hdr; + + memset(&io_hdr, 0, sizeof(struct sg_io_hdr)); + io_hdr.interface_id = 'S'; + io_hdr.cmdp = (unsigned char*) cdb; + io_hdr.cmd_len = sizeof (cdb); + io_hdr.dxferp = buf; + io_hdr.dxfer_len = buf_len; + io_hdr.sbp = sense; + io_hdr.mx_sb_len = sizeof (sense); + io_hdr.dxfer_direction = SG_DXFER_FROM_DEV; + io_hdr.timeout = COMMAND_TIMEOUT_MSEC; + + ret = ioctl(fd, SG_IO, &io_hdr); + if (ret != 0) + goto out; + } else { + goto out; + } + } + + if (!(sense[0] == 0x72 && desc[0] == 0x9 && desc[1] == 0x0c)) { errno = EIO; - return -1; + ret = -1; + goto out; } - memset(bytes, 0, 12); - bytes[1] = desc[3]; /* FEATURES */ - bytes[2] = desc[4]; /* STATUS */ - bytes[3] = desc[5]; /* SECTORS */ - bytes[9] = desc[7]; /* LBA LOW */ - bytes[8] = desc[9]; /* LBA MID */ - bytes[7] = desc[11]; /* LBA HIGH */ - bytes[10] = desc[12]; /* SELECT */ - bytes[11] = desc[13]; /* ERROR */ + out: return ret; } @@ -187,78 +268,74 @@ static void disk_identify_fixup_uint16 (uint8_t identify[512], unsigned int offs * otherwise non-zero with errno set. */ static int disk_identify (struct udev *udev, - int fd, - uint8_t out_identify[512]) + int fd, + uint8_t out_identify[512]) { int ret; - uint64_t size; - struct stat st; - uint16_t cmd[6]; - size_t len = 512; - const uint8_t *p; + uint8_t inquiry_buf[36]; + int peripheral_device_type; + int all_nul_bytes; + int n; assert (out_identify != NULL); - /* init results */ ret = -1; memset (out_identify, '\0', 512); - if ((ret = fstat(fd, &st)) < 0) - goto fail; - - if (!S_ISBLK(st.st_mode)) { - errno = ENODEV; - goto fail; - } - - /* - * do not confuse optical drive firmware with ATA commands - * some drives are reported to blank CD-RWs + /* If we were to use ATA PASS_THROUGH (12) on an ATAPI device + * we could accidentally blank media. This is because MMC's BLANK + * command has the same op-code (0x61). + * + * To prevent this from happening we bail out if the device + * isn't a Direct Access Block Device, e.g. SCSI type 0x00 + * (CD/DVD devices are type 0x05). So we send a SCSI INQUIRY + * command first... libata is handling this via its SCSI + * emulation layer. + * + * This also ensures that we're actually dealing with a device + * that understands SCSI commands. + * + * (Yes, it is a bit perverse that we're tunneling the ATA + * command through SCSI and relying on the ATA driver + * emulating SCSI well-enough...) + * + * (See commit 160b069c25690bfb0c785994c7c3710289179107 for + * the original bug-fix and see http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=556635 + * for the original bug-report.) */ - if (ioctl(fd, CDROM_GET_CAPABILITY, NULL) >= 0) { - errno = EIO; - ret = -1; - goto fail; - } - - /* So, it's a block device. Let's make sure the ioctls work */ - if ((ret = ioctl(fd, BLKGETSIZE64, &size)) < 0) - goto fail; + ret = disk_scsi_inquiry_command (fd, inquiry_buf, sizeof (inquiry_buf)); + if (ret != 0) + goto out; - if (size <= 0 || size == (uint64_t) -1) { + /* SPC-4, section 6.4.2: Standard INQUIRY data */ + peripheral_device_type = inquiry_buf[0] & 0x1f; + if (peripheral_device_type != 0x00) { + ret = -1; errno = EIO; - goto fail; + goto out; } - memset(cmd, 0, sizeof(cmd)); - cmd[1] = htons(1); - ret = disk_command(fd, - 0xEC, /* IDENTIFY DEVICE command */ - SG_DXFER_FROM_DEV, cmd, - out_identify, &len); + /* OK, now issue the IDENTIFY DEVICE command */ + ret = disk_identify_command(fd, out_identify, 512); if (ret != 0) - goto fail; + goto out; - if (len != 512) { - errno = EIO; - goto fail; - } - - /* Check if IDENTIFY data is all NULs */ - for (p = out_identify; p < (const uint8_t*) out_identify + len; p++) { - if (*p) { - p = NULL; + /* Check if IDENTIFY data is all NUL bytes - if so, bail */ + all_nul_bytes = 1; + for (n = 0; n < 512; n++) { + if (out_identify[n] != '\0') { + all_nul_bytes = 0; break; } } - if (p) { + if (all_nul_bytes) { + ret = -1; errno = EIO; - goto fail; + goto out; } - ret = 0; -fail: +out: return ret; }