diff options
| -rw-r--r-- | hw/scsi-generic.c | 653 |
1 files changed, 653 insertions, 0 deletions
diff --git a/hw/scsi-generic.c b/hw/scsi-generic.c new file mode 100644 index 0000000000..60084cff64 --- /dev/null +++ b/hw/scsi-generic.c @@ -0,0 +1,653 @@ +/* + * Generic SCSI Device support + * + * Copyright (c) 2007 Bull S.A.S. + * Based on code by Paul Brook + * Based on code by Fabrice Bellard + * + * Written by Laurent Vivier <Laurent.Vivier@bull.net> + * + * This code is licenced under the LGPL. + * + */ + +#include "qemu-common.h" +#include "block.h" +#include "scsi-disk.h" + +#ifndef __linux__ + +SCSIDevice *scsi_generic_init(BlockDriverState *bdrv, int tcq, + scsi_completionfn completion, void *opaque) +{ + return NULL; +} + +#else /* __linux__ */ + +//#define DEBUG_SCSI + +#ifdef DEBUG_SCSI +#define DPRINTF(fmt, args...) \ +do { printf("scsi-generic: " fmt , ##args); } while (0) +#else +#define DPRINTF(fmt, args...) do {} while(0) +#endif + +#define BADF(fmt, args...) \ +do { fprintf(stderr, "scsi-generic: " fmt , ##args); } while (0) + +#include <stdio.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> +#include <scsi/sg.h> +#include <scsi/scsi.h> + +#define LOAD_UNLOAD 0xa6 +#define SET_CD_SPEED 0xbb +#define BLANK 0xa1 + +#define SCSI_CMD_BUF_SIZE 16 +#define SCSI_SENSE_BUF_SIZE 32 + +#define SG_ERR_DRIVER_TIMEOUT 0x06 +#define SG_ERR_DRIVER_SENSE 0x08 + +#ifndef MAX_UINT +#define MAX_UINT ((unsigned int)-1) +#endif + +typedef struct SCSIRequest { + BlockDriverAIOCB *aiocb; + struct SCSIRequest *next; + SCSIDeviceState *dev; + uint32_t tag; + uint8_t cmd[SCSI_CMD_BUF_SIZE]; + int cmdlen; + uint8_t *buf; + int buflen; + int len; + sg_io_hdr_t io_header; +} SCSIRequest; + +struct SCSIDeviceState +{ + SCSIRequest *requests; + BlockDriverState *bdrv; + int blocksize; + int lun; + scsi_completionfn completion; + void *opaque; + int driver_status; + uint8_t sensebuf[SCSI_SENSE_BUF_SIZE]; +}; + +/* Global pool of SCSIRequest structures. */ +static SCSIRequest *free_requests = NULL; + +static SCSIRequest *scsi_new_request(SCSIDeviceState *s, uint32_t tag) +{ + SCSIRequest *r; + + if (free_requests) { + r = free_requests; + free_requests = r->next; + } else { + r = qemu_malloc(sizeof(SCSIRequest)); + r->buf = NULL; + r->buflen = 0; + } + r->dev = s; + r->tag = tag; + memset(r->cmd, 0, sizeof(r->cmd)); + memset(&r->io_header, 0, sizeof(r->io_header)); + r->cmdlen = 0; + r->len = 0; + r->aiocb = NULL; + + /* link */ + + r->next = s->requests; + s->requests = r; + return r; +} + +static void scsi_remove_request(SCSIRequest *r) +{ + SCSIRequest *last; + SCSIDeviceState *s = r->dev; + + if (s->requests == r) { + s->requests = r->next; + } else { + last = s->requests; + while (last && last->next != r) + last = last->next; + if (last) { + last->next = r->next; + } else { + BADF("Orphaned request\n"); + } + } + r->next = free_requests; + free_requests = r; +} + +static SCSIRequest *scsi_find_request(SCSIDeviceState *s, uint32_t tag) +{ + SCSIRequest *r; + + r = s->requests; + while (r && r->tag != tag) + r = r->next; + + return r; +} + +/* Helper function for command completion. */ +static void scsi_command_complete(void *opaque, int ret) +{ + SCSIRequest *r = (SCSIRequest *)opaque; + SCSIDeviceState *s = r->dev; + uint32_t tag; + int sense; + + s->driver_status = r->io_header.driver_status; + if (ret != 0) + sense = HARDWARE_ERROR; + else { + if (s->driver_status & SG_ERR_DRIVER_TIMEOUT) { + sense = HARDWARE_ERROR; + BADF("Driver Timeout\n"); + } else if ((s->driver_status & SG_ERR_DRIVER_SENSE) == 0) + sense = NO_SENSE; + else + sense = s->sensebuf[2] & 0x0f; + } + + DPRINTF("Command complete 0x%p tag=0x%x sense=%d\n", r, r->tag, sense); + tag = r->tag; + scsi_remove_request(r); + s->completion(s->opaque, SCSI_REASON_DONE, tag, sense); +} + +/* Cancel a pending data transfer. */ +static void scsi_cancel_io(SCSIDevice *d, uint32_t tag) +{ + DPRINTF("scsi_cancel_io 0x%x\n", tag); + SCSIDeviceState *s = d->state; + SCSIRequest *r; + DPRINTF("Cancel tag=0x%x\n", tag); + r = scsi_find_request(s, tag); + if (r) { + if (r->aiocb) + bdrv_aio_cancel(r->aiocb); + r->aiocb = NULL; + scsi_remove_request(r); + } +} + +static int execute_command(BlockDriverState *bdrv, + SCSIRequest *r, int direction, + BlockDriverCompletionFunc *complete) +{ + + r->io_header.interface_id = 'S'; + r->io_header.dxfer_direction = direction; + r->io_header.dxferp = r->buf; + r->io_header.dxfer_len = r->buflen; + r->io_header.cmdp = r->cmd; + r->io_header.cmd_len = r->cmdlen; + r->io_header.mx_sb_len = sizeof(r->dev->sensebuf); + r->io_header.sbp = r->dev->sensebuf; + r->io_header.timeout = MAX_UINT; + r->io_header.usr_ptr = r; + r->io_header.flags |= SG_FLAG_DIRECT_IO; + + if (bdrv_pwrite(bdrv, -1, &r->io_header, sizeof(r->io_header)) == -1) { + BADF("execute_command: write failed ! (%d)\n", errno); + return -1; + } + if (complete == NULL) { + int ret; + r->aiocb = NULL; + while ((ret = bdrv_pread(bdrv, -1, &r->io_header, + sizeof(r->io_header))) == -1 && + errno == EINTR); + if (ret == -1) { + BADF("execute_command: read failed !\n"); + return -1; + } + return 0; + } + + r->aiocb = bdrv_aio_read(bdrv, 0, (uint8_t*)&r->io_header, + -(int64_t)sizeof(r->io_header), complete, r); + if (r->aiocb == NULL) { + BADF("execute_command: read failed !\n"); + return -1; + } + + return 0; +} + +static void scsi_read_complete(void * opaque, int ret) +{ + SCSIRequest *r = (SCSIRequest *)opaque; + SCSIDeviceState *s = r->dev; + int len; + + if (ret) { + DPRINTF("IO error\n"); + scsi_command_complete(r, ret); + return; + } + len = r->io_header.dxfer_len - r->io_header.resid; + DPRINTF("Data ready tag=0x%x len=%d\n", r->tag, len); + + r->len = -1; + s->completion(s->opaque, SCSI_REASON_DATA, r->tag, len); +} + +/* Read more data from scsi device into buffer. */ +static void scsi_read_data(SCSIDevice *d, uint32_t tag) +{ + SCSIDeviceState *s = d->state; + SCSIRequest *r; + int ret; + + DPRINTF("scsi_read_data 0x%x\n", tag); + r = scsi_find_request(s, tag); + if (!r) { + BADF("Bad read tag 0x%x\n", tag); + /* ??? This is the wrong error. */ + scsi_command_complete(r, -EINVAL); + return; + } + + if (r->len == -1) { + scsi_command_complete(r, 0); + return; + } + + if (r->cmd[0] == REQUEST_SENSE && s->driver_status & SG_ERR_DRIVER_SENSE) + { + memcpy(r->buf, s->sensebuf, 16); + r->io_header.driver_status = 0; + r->len = -1; + s->completion(s->opaque, SCSI_REASON_DATA, r->tag, 16); + return; + } + + ret = execute_command(s->bdrv, r, SG_DXFER_FROM_DEV, scsi_read_complete); + if (ret == -1) { + scsi_command_complete(r, -EINVAL); + return; + } +} + +static void scsi_write_complete(void * opaque, int ret) +{ + SCSIRequest *r = (SCSIRequest *)opaque; + + DPRINTF("scsi_write_complete() ret = %d\n", ret); + if (ret) { + DPRINTF("IO error\n"); + scsi_command_complete(r, ret); + return; + } + + scsi_command_complete(r, ret); +} + +/* Write data to a scsi device. Returns nonzero on failure. + The transfer may complete asynchronously. */ +static int scsi_write_data(SCSIDevice *d, uint32_t tag) +{ + SCSIDeviceState *s = d->state; + SCSIRequest *r; + int ret; + + DPRINTF("scsi_write_data 0x%x\n", tag); + r = scsi_find_request(s, tag); + if (!r) { + BADF("Bad write tag 0x%x\n", tag); + /* ??? This is the wrong error. */ + scsi_command_complete(r, -EINVAL); + return 0; + } + + if (r->len == 0) { + r->len = r->buflen; + s->completion(s->opaque, SCSI_REASON_DATA, r->tag, r->len); + return 0; + } + + ret = execute_command(s->bdrv, r, SG_DXFER_TO_DEV, scsi_write_complete); + if (ret == -1) { + scsi_command_complete(r, -EINVAL); + return 1; + } + + return 0; +} + +/* Return a pointer to the data buffer. */ +static uint8_t *scsi_get_buf(SCSIDevice *d, uint32_t tag) +{ + SCSIDeviceState *s = d->state; + SCSIRequest *r; + r = scsi_find_request(s, tag); + if (!r) { + BADF("Bad buffer tag 0x%x\n", tag); + return NULL; + } + return r->buf; +} + +static int scsi_length(uint8_t *cmd, int blocksize, int *cmdlen, uint32_t *len) +{ + switch (cmd[0] >> 5) { + case 0: + *len = cmd[4]; + *cmdlen = 6; + break; + case 1: + case 2: + *len = cmd[8] | (cmd[7] << 8); + *cmdlen = 10; + break; + case 4: + *len = cmd[13] | (cmd[12] << 8) | (cmd[11] << 16) | (cmd[10] << 24); + *cmdlen = 16; + break; + case 5: + *len = cmd[9] | (cmd[8] << 8) | (cmd[7] << 16) | (cmd[6] << 24); + *cmdlen = 12; + break; + default: + return -1; + } + + switch(cmd[0]) { + case TEST_UNIT_READY: + case REZERO_UNIT: + case START_STOP: + case SEEK_6: + case WRITE_FILEMARKS: + case SPACE: + case ERASE: + case ALLOW_MEDIUM_REMOVAL: + case VERIFY: + case SEEK_10: + case SYNCHRONIZE_CACHE: + case LOCK_UNLOCK_CACHE: + case LOAD_UNLOAD: + case SET_CD_SPEED: + case SET_LIMITS: + case WRITE_LONG: + case MOVE_MEDIUM: + case UPDATE_BLOCK: + *len = 0; + break; + case MODE_SENSE: + break; + case WRITE_SAME: + *len = 1; + break; + case READ_CAPACITY: + *len = 8; + break; + case READ_BLOCK_LIMITS: + *len = 6; + break; + case READ_POSITION: + *len = 20; + break; + case SEND_VOLUME_TAG: + *len *= 40; + break; + case MEDIUM_SCAN: + *len *= 8; + break; + case WRITE_10: + cmd[1] &= ~0x08; /* disable FUA */ + case WRITE_VERIFY: + case WRITE_6: + case WRITE_12: + case WRITE_VERIFY_12: + *len *= blocksize; + break; + case READ_10: + cmd[1] &= ~0x08; /* disable FUA */ + case READ_6: + case READ_REVERSE: + case RECOVER_BUFFERED_DATA: + case READ_12: + *len *= blocksize; + break; + } + return 0; +} + +static int is_write(int command) +{ + switch (command) { + case COPY: + case COPY_VERIFY: + case COMPARE: + case CHANGE_DEFINITION: + case LOG_SELECT: + case MODE_SELECT: + case MODE_SELECT_10: + case SEND_DIAGNOSTIC: + case WRITE_BUFFER: + case FORMAT_UNIT: + case REASSIGN_BLOCKS: + case RESERVE: + case SEARCH_EQUAL: + case SEARCH_HIGH: + case SEARCH_LOW: + case WRITE_6: + case WRITE_10: + case WRITE_VERIFY: + case UPDATE_BLOCK: + case WRITE_LONG: + case WRITE_SAME: + case SEARCH_HIGH_12: + case SEARCH_EQUAL_12: + case SEARCH_LOW_12: + case WRITE_12: + case WRITE_VERIFY_12: + case SET_WINDOW: + case MEDIUM_SCAN: + case SEND_VOLUME_TAG: + case WRITE_LONG_2: + return 1; + } + return 0; +} + +/* Execute a scsi command. Returns the length of the data expected by the + command. This will be Positive for data transfers from the device + (eg. disk reads), negative for transfers to the device (eg. disk writes), + and zero if the command does not transfer any data. */ + +static int32_t scsi_send_command(SCSIDevice *d, uint32_t tag, + uint8_t *cmd, int lun) +{ + SCSIDeviceState *s = d->state; + uint32_t len; + int cmdlen; + SCSIRequest *r; + int ret; + + /* ??? Tags are not unique for different luns. We only implement a + single lun, so this should not matter. */ + + if (lun != s->lun || (cmd[1] >> 5) != s->lun) { + DPRINTF("Unimplemented LUN %d\n", lun ? lun : cmd[1] >> 5); + s->completion(s->opaque, SCSI_REASON_DONE, tag, ILLEGAL_REQUEST); + return 0; + } + + if (scsi_length(cmd, s->blocksize, &cmdlen, &len) == -1) { + BADF("Unsupported command length, command %x\n", cmd[0]); + return 0; + } + + DPRINTF("Command: lun=%d tag=0x%x data=0x%02x len %d\n", lun, tag, + cmd[0], len); + + r = scsi_find_request(s, tag); + if (r) { + BADF("Tag 0x%x already in use %p\n", tag, r); + scsi_cancel_io(d, tag); + } + r = scsi_new_request(s, tag); + + memcpy(r->cmd, cmd, cmdlen); + r->cmdlen = cmdlen; + + if (len == 0) { + if (r->buf != NULL) + free(r->buf); + r->buflen = 0; + r->buf = NULL; + ret = execute_command(s->bdrv, r, SG_DXFER_NONE, scsi_command_complete); + if (ret == -1) { + scsi_command_complete(r, -EINVAL); + return 0; + } + return 0; + } + + if (r->buflen != len) { + if (r->buf != NULL) + free(r->buf); + r->buf = qemu_malloc(len); + r->buflen = len; + } + + memset(r->buf, 0, r->buflen); + r->len = len; + if (is_write(cmd[0])) { + r->len = 0; + return -len; + } + + return len; +} + +static int get_blocksize(BlockDriverState *bdrv) +{ + uint8_t cmd[10]; + uint8_t buf[8]; + uint8_t sensebuf[8]; + sg_io_hdr_t io_header; + int ret; + + memset(cmd, sizeof(cmd), 0); + memset(buf, sizeof(buf), 0); + cmd[0] = READ_CAPACITY; + + memset(&io_header, 0, sizeof(io_header)); + io_header.interface_id = 'S'; + io_header.dxfer_direction = SG_DXFER_FROM_DEV; + io_header.dxfer_len = sizeof(buf); + io_header.dxferp = buf; + io_header.cmdp = cmd; + io_header.cmd_len = sizeof(cmd); + io_header.mx_sb_len = sizeof(sensebuf); + io_header.sbp = sensebuf; + io_header.timeout = 6000; /* XXX */ + + ret = bdrv_pwrite(bdrv, -1, &io_header, sizeof(io_header)); + if (ret == -1) + return -1; + + while ((ret = bdrv_pread(bdrv, -1, &io_header, sizeof(io_header))) == -1 && + errno == EINTR); + + if (ret == -1) + return -1; + + return (buf[4] << 24) | (buf[5] << 16) | (buf[6] << 8) | buf[7]; +} + +static void scsi_destroy(SCSIDevice *d) +{ + SCSIRequest *r, *n; + + r = d->state->requests; + while (r) { + n = r->next; + qemu_free(r); + r = n; + } + + r = free_requests; + while (r) { + n = r->next; + qemu_free(r); + r = n; + } + + qemu_free(d->state); + qemu_free(d); +} + +SCSIDevice *scsi_generic_init(BlockDriverState *bdrv, int tcq, + scsi_completionfn completion, void *opaque) +{ + int sg_version; + SCSIDevice *d; + SCSIDeviceState *s; + struct sg_scsi_id scsiid; + + /* check we are really using a /dev/sg* file */ + + if (!bdrv_is_sg(bdrv)) + return NULL; + + /* check we are using a driver managing SG_IO (version 3 and after */ + + if (bdrv_ioctl(bdrv, SG_GET_VERSION_NUM, &sg_version) < 0 || + sg_version < 30000) + return NULL; + + /* get LUN of the /dev/sg? */ + + if (bdrv_ioctl(bdrv, SG_GET_SCSI_ID, &scsiid)) + return NULL; + + /* define device state */ + + s = (SCSIDeviceState *)qemu_mallocz(sizeof(SCSIDeviceState)); + s->bdrv = bdrv; + s->requests = NULL; + s->completion = completion; + s->opaque = opaque; + s->lun = scsiid.lun; + s->blocksize = get_blocksize(s->bdrv); + s->driver_status = 0; + memset(s->sensebuf, 0, sizeof(s->sensebuf)); + /* removable media returns 0 if not present */ + if (s->blocksize <= 0) + s->blocksize = 2048; + + /* define function to manage device */ + + d = (SCSIDevice *)qemu_mallocz(sizeof(SCSIDevice)); + d->state = s; + d->destroy = scsi_destroy; + d->send_command = scsi_send_command; + d->read_data = scsi_read_data; + d->write_data = scsi_write_data; + d->cancel_io = scsi_cancel_io; + d->get_buf = scsi_get_buf; + + return d; +} +#endif /* __linux__ */ |