diff options
Diffstat (limited to 'hw/scsi-disk.c')
| -rw-r--r-- | hw/scsi-disk.c | 152 |
1 files changed, 118 insertions, 34 deletions
diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c index 3419c8e2d2..a2f299e951 100644 --- a/hw/scsi-disk.c +++ b/hw/scsi-disk.c @@ -25,6 +25,7 @@ do { fprintf(stderr, "scsi-disk: " fmt , ##args); } while (0) #define SENSE_NO_SENSE 0 #define SENSE_NOT_READY 2 +#define SENSE_HARDWARE_ERROR 4 #define SENSE_ILLEGAL_REQUEST 5 struct SCSIDevice @@ -46,7 +47,13 @@ struct SCSIDevice int buf_pos; int buf_len; int sense; + BlockDriverAIOCB *aiocb; + /* Data still to be transfered after this request completes. */ + uint8_t *aiodata; + uint32_t aiolen; char buf[512]; + /* Completion functions may be called from either scsi_{read,write}_data + or from the AIO completion routines. */ scsi_completionfn completion; void *opaque; }; @@ -54,10 +61,49 @@ struct SCSIDevice static void scsi_command_complete(SCSIDevice *s, int sense) { s->sense = sense; - s->completion(s->opaque, s->tag, sense); + s->completion(s->opaque, SCSI_REASON_DONE, sense); } -/* Read data from a scsi device. Returns nonzero on failure. */ +static void scsi_transfer_complete(SCSIDevice *s) +{ + s->completion(s->opaque, SCSI_REASON_DATA, 0); + s->aiocb = NULL; +} + +static void scsi_read_complete(void * opaque, int ret) +{ + SCSIDevice *s = (SCSIDevice *)opaque; + + if (ret) { + DPRINTF("IO error\n"); + scsi_command_complete(s, SENSE_HARDWARE_ERROR); + } + + if (s->aiolen) { + /* Read the remaining data. Full and partial sectors are transferred + separately. */ + scsi_read_data(s, s->aiodata, s->aiolen); + } else { + if (s->buf_len == 0 && s->sector_count == 0) + scsi_command_complete(s, SENSE_NO_SENSE); + else + scsi_transfer_complete(s); + } +} + +/* Cancel a pending data transfer. */ +void scsi_cancel_io(SCSIDevice *s) +{ + if (!s->aiocb) { + BADF("Cancel with no pending IO\n"); + return; + } + bdrv_aio_cancel(s->aiocb); + s->aiocb = NULL; +} + +/* Read data from a scsi device. Returns nonzero on failure. + The transfer may complete asynchronously. */ int scsi_read_data(SCSIDevice *s, uint8_t *data, uint32_t len) { uint32_t n; @@ -84,14 +130,19 @@ int scsi_read_data(SCSIDevice *s, uint8_t *data, uint32_t len) n = s->sector_count; if (n != 0) { - bdrv_read(s->bdrv, s->sector, data, n); - data += n * 512; - len -= n * 512; + s->aiolen = len - n * 512; + s->aiodata = data + n * 512; + s->aiocb = bdrv_aio_read(s->bdrv, s->sector, data, n, + scsi_read_complete, s); + if (s->aiocb == NULL) + scsi_command_complete(s, SENSE_HARDWARE_ERROR); s->sector += n; s->sector_count -= n; + return 0; } if (len && s->sector_count) { + /* TODO: Make this use AIO. */ bdrv_read(s->bdrv, s->sector, s->buf, 1); s->sector++; s->sector_count--; @@ -106,11 +157,53 @@ int scsi_read_data(SCSIDevice *s, uint8_t *data, uint32_t len) if (s->buf_len == 0 && s->sector_count == 0) scsi_command_complete(s, SENSE_NO_SENSE); + else + scsi_transfer_complete(s); return 0; } -/* Read data to a scsi device. Returns nonzero on failure. */ +static void scsi_write_complete(void * opaque, int ret) +{ + SCSIDevice *s = (SCSIDevice *)opaque; + + if (ret) { + fprintf(stderr, "scsi-disc: IO write error\n"); + exit(1); + } + + if (s->sector_count == 0) + scsi_command_complete(s, SENSE_NO_SENSE); + else + scsi_transfer_complete(s); +} + +static uint32_t scsi_write_partial_sector(SCSIDevice *s, uint8_t *data, + uint32_t len) +{ + int n; + + n = 512 - s->buf_len; + if (n > len) + n = len; + + memcpy(s->buf + s->buf_len, data, n); + data += n; + s->buf_len += n; + len -= n; + if (s->buf_len == 512) { + /* A full sector has been accumulated. Write it to disk. */ + /* TODO: Make this use async IO. */ + bdrv_write(s->bdrv, s->sector, s->buf, 1); + s->buf_len = 0; + s->sector++; + s->sector_count--; + } + return n; +} + +/* Write data to a scsi device. Returns nonzero on failure. + The transfer may complete asynchronously. */ int scsi_write_data(SCSIDevice *s, uint8_t *data, uint32_t len) { uint32_t n; @@ -125,48 +218,39 @@ int scsi_write_data(SCSIDevice *s, uint8_t *data, uint32_t len) return 1; if (s->buf_len != 0 || len < 512) { - n = 512 - s->buf_len; - if (n > len) - n = len; - - memcpy(s->buf + s->buf_len, data, n); - data += n; - s->buf_len += n; + n = scsi_write_partial_sector(s, data, len); len -= n; - if (s->buf_len == 512) { - /* A full sector has been accumulated. Write it to disk. */ - bdrv_write(s->bdrv, s->sector, s->buf, 1); - s->buf_len = 0; - s->sector++; - s->sector_count--; - } + data += n; } n = len / 512; if (n > s->sector_count) - n = s->sector_count; + return 1; if (n != 0) { - bdrv_write(s->bdrv, s->sector, data, n); + s->aiocb = bdrv_aio_write(s->bdrv, s->sector, data, n, + scsi_write_complete, s); + if (s->aiocb == NULL) + scsi_command_complete(s, SENSE_HARDWARE_ERROR); data += n * 512; len -= n * 512; s->sector += n; s->sector_count -= n; } - if (len >= 512) - return 1; - - if (len && s->sector_count) { - /* Recurse to complete the partial write. */ - return scsi_write_data(s, data, len); + if (len) { + if (s->sector_count == 0) + return 1; + /* Complete a partial write. */ + scsi_write_partial_sector(s, data, len); + } + if (n == 0) { + /* Transfer completes immediately. */ + if (s->sector_count == 0) + scsi_command_complete(s, SENSE_NO_SENSE); + else + scsi_transfer_complete(s); } - - if (len != 0) - return 1; - - if (s->sector_count == 0) - scsi_command_complete(s, SENSE_NO_SENSE); return 0; } |