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* [Qemu-devel] [PATCH v2] Real SCSI device passthrough
@ 2007-12-06 13:37 Laurent Vivier
  2007-12-06 15:30 ` Anthony Liguori
  0 siblings, 1 reply; 3+ messages in thread
From: Laurent Vivier @ 2007-12-06 13:37 UTC (permalink / raw)
  Cc: qemu-devel


This patch allows to connect the virtual SCSI interface of Qemu to
a real SCSI device of the host.
Using the devices /dev/sg, it allows to send the SCSI commands from the
virtual SCSI interface to the real device.

It has been tested with a SATA disk and an ATA CD burner with ide-scsi module 
and wodim to burn a CD-RW.

v2 improves Timeout and management of REQUEST_SENSE command.

Laurent
---
 Makefile          |    1 
 block-raw.c       |   28 +-
 block.c           |   17 +
 block.h           |    2 
 block_int.h       |    4 
 hw/esp.c          |   20 -
 hw/lsi53c895a.c   |   49 ++-
 hw/scsi-disk.c    |   62 +++--
 hw/scsi-disk.h    |   29 +-
 hw/scsi-generic.c |  667 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 hw/usb-msd.c      |   16 -
 11 files changed, 820 insertions(+), 75 deletions(-)

Index: qemu/block-raw.c
===================================================================
--- qemu.orig/block-raw.c	2007-12-06 09:30:27.000000000 +0100
+++ qemu/block-raw.c	2007-12-06 09:30:37.000000000 +0100
@@ -52,6 +52,7 @@
 #include <sys/ioctl.h>
 #include <linux/cdrom.h>
 #include <linux/fd.h>
+#include <linux/major.h>
 #endif
 #ifdef __FreeBSD__
 #include <sys/disk.h>
@@ -152,7 +153,7 @@ static int raw_pread(BlockDriverState *b
     if (ret < 0)
         return ret;
 
-    if (lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
+    if (offset >= 0 && lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
         ++(s->lseek_err_cnt);
         if(s->lseek_err_cnt <= 10) {
             DEBUG_BLOCK_PRINT("raw_pread(%d:%s, %" PRId64 ", %p, %d) [%" PRId64
@@ -205,7 +206,7 @@ static int raw_pwrite(BlockDriverState *
     if (ret < 0)
         return ret;
 
-    if (lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
+    if (offset >= 0 && lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
         ++(s->lseek_err_cnt);
         if(s->lseek_err_cnt) {
             DEBUG_BLOCK_PRINT("raw_pwrite(%d:%s, %" PRId64 ", %p, %d) [%"
@@ -277,8 +278,8 @@ void qemu_aio_init(void)
            seems to fix the problem. */
         struct aioinit ai;
         memset(&ai, 0, sizeof(ai));
-        ai.aio_threads = 1;
-        ai.aio_num = 1;
+        ai.aio_threads = 16;
+        ai.aio_num = 16;
         ai.aio_idle_time = 365 * 100000;
         aio_init(&ai);
     }
@@ -388,7 +389,10 @@ static RawAIOCB *raw_aio_setup(BlockDriv
     acb->aiocb.aio_sigevent.sigev_signo = aio_sig_num;
     acb->aiocb.aio_sigevent.sigev_notify = SIGEV_SIGNAL;
     acb->aiocb.aio_buf = buf;
-    acb->aiocb.aio_nbytes = nb_sectors * 512;
+    if (nb_sectors < 0)
+        acb->aiocb.aio_nbytes = -nb_sectors;
+    else
+        acb->aiocb.aio_nbytes = nb_sectors * 512;
     acb->aiocb.aio_offset = sector_num * 512;
     acb->next = first_aio;
     first_aio = acb;
@@ -680,6 +684,8 @@ static int hdev_open(BlockDriverState *b
         s->fd_open_flags = open_flags;
         /* open will not fail even if no floppy is inserted */
         open_flags |= O_NONBLOCK;
+    } else if (strstart(filename, "/dev/sg", NULL)) {
+        bs->sg = 1;
     }
 #endif
     fd = open(filename, open_flags, 0644);
@@ -859,6 +865,12 @@ static int raw_set_locked(BlockDriverSta
     return 0;
 }
 
+static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
+{
+    BDRVRawState *s = bs->opaque;
+
+    return ioctl(s->fd, req, buf);
+}
 #else
 
 static int raw_is_inserted(BlockDriverState *bs)
@@ -881,6 +893,10 @@ static int raw_set_locked(BlockDriverSta
     return -ENOTSUP;
 }
 
+static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
+{
+    return -ENOTSUP;
+}
 #endif /* !linux */
 
 BlockDriver bdrv_host_device = {
@@ -907,6 +923,8 @@ BlockDriver bdrv_host_device = {
     .bdrv_media_changed = raw_media_changed,
     .bdrv_eject = raw_eject,
     .bdrv_set_locked = raw_set_locked,
+    /* generic scsi device */
+    .bdrv_ioctl = raw_ioctl,
 };
 
 #else /* _WIN32 */
Index: qemu/block.c
===================================================================
--- qemu.orig/block.c	2007-12-06 09:30:31.000000000 +0100
+++ qemu/block.c	2007-12-06 09:30:37.000000000 +0100
@@ -303,7 +303,6 @@ int bdrv_file_open(BlockDriverState **pb
 {
     BlockDriverState *bs;
     int ret;
-
     bs = bdrv_new("");
     if (!bs)
         return -ENOMEM;
@@ -796,6 +795,11 @@ int bdrv_is_cached(BlockDriverState *bs)
     return bs->cache;
 }
 
+int bdrv_is_sg(BlockDriverState *bs)
+{
+    return bs->sg;
+}
+
 /* XXX: no longer used */
 void bdrv_set_change_cb(BlockDriverState *bs,
                         void (*change_cb)(void *opaque), void *opaque)
@@ -1404,3 +1408,14 @@ void bdrv_set_locked(BlockDriverState *b
         drv->bdrv_set_locked(bs, locked);
     }
 }
+
+/* needed for generic scsi interface */
+
+int bdrv_ioctl(BlockDriverState *bs,  unsigned long int req, void *buf)
+{
+    BlockDriver *drv = bs->drv;
+
+    if (drv && drv->bdrv_ioctl)
+        return drv->bdrv_ioctl(bs, req, buf);
+    return -ENOTSUP;
+}
Index: qemu/block.h
===================================================================
--- qemu.orig/block.h	2007-12-06 09:30:31.000000000 +0100
+++ qemu/block.h	2007-12-06 09:30:37.000000000 +0100
@@ -120,6 +120,7 @@ int bdrv_get_type_hint(BlockDriverState 
 int bdrv_get_translation_hint(BlockDriverState *bs);
 int bdrv_is_removable(BlockDriverState *bs);
 int bdrv_is_read_only(BlockDriverState *bs);
+int bdrv_is_sg(BlockDriverState *bs);
 int bdrv_is_inserted(BlockDriverState *bs);
 int bdrv_is_cached(BlockDriverState *bs);
 int bdrv_media_changed(BlockDriverState *bs);
@@ -150,6 +151,7 @@ int bdrv_snapshot_delete(BlockDriverStat
 int bdrv_snapshot_list(BlockDriverState *bs,
                        QEMUSnapshotInfo **psn_info);
 char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn);
+int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf);
 
 char *get_human_readable_size(char *buf, int buf_size, int64_t size);
 int path_is_absolute(const char *path);
Index: qemu/block_int.h
===================================================================
--- qemu.orig/block_int.h	2007-12-06 09:30:31.000000000 +0100
+++ qemu/block_int.h	2007-12-06 09:30:37.000000000 +0100
@@ -82,6 +82,9 @@ struct BlockDriver {
     int (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
     int (*bdrv_set_locked)(BlockDriverState *bs, int locked);
 
+    /* to control generic scsi devices */
+    int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, char *buf);
+
     BlockDriverAIOCB *free_aiocb;
     struct BlockDriver *next;
 };
@@ -93,6 +96,7 @@ struct BlockDriverState {
     int removable; /* if true, the media can be removed */
     int locked;    /* if true, the media cannot temporarily be ejected */
     int encrypted; /* if true, the media is encrypted */
+    int sg;        /* if true, the device is a /dev/sg* */
     /* event callback when inserting/removing */
     void (*change_cb)(void *opaque);
     void *change_opaque;
Index: qemu/hw/scsi-disk.c
===================================================================
--- qemu.orig/hw/scsi-disk.c	2007-12-06 09:30:27.000000000 +0100
+++ qemu/hw/scsi-disk.c	2007-12-06 09:30:37.000000000 +0100
@@ -37,7 +37,7 @@ do { fprintf(stderr, "scsi-disk: " fmt ,
 #define SCSI_DMA_BUF_SIZE    65536
 
 typedef struct SCSIRequest {
-    SCSIDevice *dev;
+    SCSIDeviceState *dev;
     uint32_t tag;
     /* ??? We should probably keep track of whether the data trasfer is
        a read or a write.  Currently we rely on the host getting it right.  */
@@ -51,7 +51,7 @@ typedef struct SCSIRequest {
     struct SCSIRequest *next;
 } SCSIRequest;
 
-struct SCSIDevice
+struct SCSIDeviceState
 {
     BlockDriverState *bdrv;
     SCSIRequest *requests;
@@ -69,7 +69,7 @@ struct SCSIDevice
 /* Global pool of SCSIRequest structures.  */
 static SCSIRequest *free_requests = NULL;
 
-static SCSIRequest *scsi_new_request(SCSIDevice *s, uint32_t tag)
+static SCSIRequest *scsi_new_request(SCSIDeviceState *s, uint32_t tag)
 {
     SCSIRequest *r;
 
@@ -94,7 +94,7 @@ static SCSIRequest *scsi_new_request(SCS
 static void scsi_remove_request(SCSIRequest *r)
 {
     SCSIRequest *last;
-    SCSIDevice *s = r->dev;
+    SCSIDeviceState *s = r->dev;
 
     if (s->requests == r) {
         s->requests = r->next;
@@ -112,7 +112,7 @@ static void scsi_remove_request(SCSIRequ
     free_requests = r;
 }
 
-static SCSIRequest *scsi_find_request(SCSIDevice *s, uint32_t tag)
+static SCSIRequest *scsi_find_request(SCSIDeviceState *s, uint32_t tag)
 {
     SCSIRequest *r;
 
@@ -126,7 +126,7 @@ static SCSIRequest *scsi_find_request(SC
 /* Helper function for command completion.  */
 static void scsi_command_complete(SCSIRequest *r, int sense)
 {
-    SCSIDevice *s = r->dev;
+    SCSIDeviceState *s = r->dev;
     uint32_t tag;
     DPRINTF("Command complete tag=0x%x sense=%d\n", r->tag, sense);
     s->sense = sense;
@@ -136,8 +136,9 @@ static void scsi_command_complete(SCSIRe
 }
 
 /* Cancel a pending data transfer.  */
-void scsi_cancel_io(SCSIDevice *s, uint32_t tag)
+static void scsi_cancel_io(SCSIDevice *d, uint32_t tag)
 {
+    SCSIDeviceState *s = d->state;
     SCSIRequest *r;
     DPRINTF("Cancel tag=0x%x\n", tag);
     r = scsi_find_request(s, tag);
@@ -152,7 +153,7 @@ void scsi_cancel_io(SCSIDevice *s, uint3
 static void scsi_read_complete(void * opaque, int ret)
 {
     SCSIRequest *r = (SCSIRequest *)opaque;
-    SCSIDevice *s = r->dev;
+    SCSIDeviceState *s = r->dev;
 
     if (ret) {
         DPRINTF("IO error\n");
@@ -165,8 +166,9 @@ static void scsi_read_complete(void * op
 }
 
 /* Read more data from scsi device into buffer.  */
-void scsi_read_data(SCSIDevice *s, uint32_t tag)
+static void scsi_read_data(SCSIDevice *d, uint32_t tag)
 {
+    SCSIDeviceState *s = d->state;
     SCSIRequest *r;
     uint32_t n;
 
@@ -205,7 +207,7 @@ void scsi_read_data(SCSIDevice *s, uint3
 static void scsi_write_complete(void * opaque, int ret)
 {
     SCSIRequest *r = (SCSIRequest *)opaque;
-    SCSIDevice *s = r->dev;
+    SCSIDeviceState *s = r->dev;
     uint32_t len;
 
     if (ret) {
@@ -229,8 +231,9 @@ static void scsi_write_complete(void * o
 
 /* Write data to a scsi device.  Returns nonzero on failure.
    The transfer may complete asynchronously.  */
-int scsi_write_data(SCSIDevice *s, uint32_t tag)
+static int scsi_write_data(SCSIDevice *d, uint32_t tag)
 {
+    SCSIDeviceState *s = d->state;
     SCSIRequest *r;
     uint32_t n;
 
@@ -260,8 +263,9 @@ int scsi_write_data(SCSIDevice *s, uint3
 }
 
 /* Return a pointer to the data buffer.  */
-uint8_t *scsi_get_buf(SCSIDevice *s, uint32_t tag)
+static uint8_t *scsi_get_buf(SCSIDevice *d, uint32_t tag)
 {
+    SCSIDeviceState *s = d->state;
     SCSIRequest *r;
 
     r = scsi_find_request(s, tag);
@@ -277,8 +281,10 @@ uint8_t *scsi_get_buf(SCSIDevice *s, uin
    (eg. disk reads), negative for transfers to the device (eg. disk writes),
    and zero if the command does not transfer any data.  */
 
-int32_t scsi_send_command(SCSIDevice *s, uint32_t tag, uint8_t *buf, int lun)
+static int32_t scsi_send_command(SCSIDevice *d, uint32_t tag,
+                                 uint8_t *buf, int lun)
 {
+    SCSIDeviceState *s = d->state;
     int64_t nb_sectors;
     uint32_t lba;
     uint32_t len;
@@ -292,7 +298,7 @@ int32_t scsi_send_command(SCSIDevice *s,
     r = scsi_find_request(s, tag);
     if (r) {
         BADF("Tag 0x%x already in use\n", tag);
-        scsi_cancel_io(s, tag);
+        scsi_cancel_io(d, tag);
     }
     /* ??? Tags are not unique for different luns.  We only implement a
        single lun, so this should not matter.  */
@@ -577,19 +583,19 @@ int32_t scsi_send_command(SCSIDevice *s,
     }
 }
 
-void scsi_disk_destroy(SCSIDevice *s)
+static void scsi_destroy(SCSIDevice *d)
 {
-    qemu_free(s);
+    qemu_free(d->state);
+    qemu_free(d);
 }
 
-SCSIDevice *scsi_disk_init(BlockDriverState *bdrv,
-                           int tcq,
-                           scsi_completionfn completion,
-                           void *opaque)
+SCSIDevice *scsi_disk_init(BlockDriverState *bdrv, int tcq,
+                           scsi_completionfn completion, void *opaque)
 {
-    SCSIDevice *s;
+    SCSIDevice *d;
+    SCSIDeviceState *s;
 
-    s = (SCSIDevice *)qemu_mallocz(sizeof(SCSIDevice));
+    s = (SCSIDeviceState *)qemu_mallocz(sizeof(SCSIDeviceState));
     s->bdrv = bdrv;
     s->tcq = tcq;
     s->completion = completion;
@@ -600,6 +606,14 @@ SCSIDevice *scsi_disk_init(BlockDriverSt
         s->cluster_size = 1;
     }
 
-    return s;
-}
+    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;
+}
Index: qemu/hw/esp.c
===================================================================
--- qemu.orig/hw/esp.c	2007-12-06 09:28:36.000000000 +0100
+++ qemu/hw/esp.c	2007-12-06 09:30:37.000000000 +0100
@@ -165,7 +165,7 @@ static int get_cmd(ESPState *s, uint8_t 
 
     if (s->current_dev) {
         /* Started a new command before the old one finished.  Cancel it.  */
-        scsi_cancel_io(s->current_dev, 0);
+        s->current_dev->cancel_io(s->current_dev, 0);
         s->async_len = 0;
     }
 
@@ -188,7 +188,7 @@ static void do_cmd(ESPState *s, uint8_t 
 
     DPRINTF("do_cmd: busid 0x%x\n", buf[0]);
     lun = buf[0] & 7;
-    datalen = scsi_send_command(s->current_dev, 0, &buf[1], lun);
+    datalen = s->current_dev->send_command(s->current_dev, 0, &buf[1], lun);
     s->ti_size = datalen;
     if (datalen != 0) {
         s->rregs[ESP_RSTAT] = STAT_IN | STAT_TC;
@@ -196,10 +196,10 @@ static void do_cmd(ESPState *s, uint8_t 
         s->dma_counter = 0;
         if (datalen > 0) {
             s->rregs[ESP_RSTAT] |= STAT_DI;
-            scsi_read_data(s->current_dev, 0);
+            s->current_dev->read_data(s->current_dev, 0);
         } else {
             s->rregs[ESP_RSTAT] |= STAT_DO;
-            scsi_write_data(s->current_dev, 0);
+            s->current_dev->write_data(s->current_dev, 0);
         }
     }
     s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
@@ -298,9 +298,9 @@ static void esp_do_dma(ESPState *s)
     if (s->async_len == 0) {
         if (to_device) {
             // ti_size is negative
-            scsi_write_data(s->current_dev, 0);
+            s->current_dev->write_data(s->current_dev, 0);
         } else {
-            scsi_read_data(s->current_dev, 0);
+            s->current_dev->read_data(s->current_dev, 0);
             /* If there is still data to be read from the device then
                complete the DMA operation immeriately.  Otherwise defer
                until the scsi layer has completed.  */
@@ -335,7 +335,7 @@ static void esp_command_complete(void *o
     } else {
         DPRINTF("transfer %d/%d\n", s->dma_left, s->ti_size);
         s->async_len = arg;
-        s->async_buf = scsi_get_buf(s->current_dev, 0);
+        s->async_buf = s->current_dev->get_buf(s->current_dev, 0);
         if (s->dma_left) {
             esp_do_dma(s);
         } else if (s->dma_counter != 0 && s->ti_size <= 0) {
@@ -611,11 +611,13 @@ void esp_scsi_attach(void *opaque, Block
     }
     if (s->scsi_dev[id]) {
         DPRINTF("Destroying device %d\n", id);
-        scsi_disk_destroy(s->scsi_dev[id]);
+        s->scsi_dev[id]->destroy(s->scsi_dev[id]);
     }
     DPRINTF("Attaching block device %d\n", id);
     /* Command queueing is not implemented.  */
-    s->scsi_dev[id] = scsi_disk_init(bd, 0, esp_command_complete, s);
+    s->scsi_dev[id] = scsi_generic_init(bd, 0, esp_command_complete, s);
+    if (s->scsi_dev[id] == NULL)
+        s->scsi_dev[id] = scsi_disk_init(bd, 0, esp_command_complete, s);
 }
 
 void *esp_init(target_phys_addr_t espaddr,
Index: qemu/hw/lsi53c895a.c
===================================================================
--- qemu.orig/hw/lsi53c895a.c	2007-12-06 09:28:36.000000000 +0100
+++ qemu/hw/lsi53c895a.c	2007-12-06 09:30:37.000000000 +0100
@@ -187,6 +187,7 @@ typedef struct {
     /* The tag is a combination of the device ID and the SCSI tag.  */
     uint32_t current_tag;
     uint32_t current_dma_len;
+    int command_complete;
     uint8_t *dma_buf;
     lsi_queue *queue;
     int queue_len;
@@ -465,7 +466,8 @@ static void lsi_do_dma(LSIState *s, int 
     s->dbc -= count;
 
     if (s->dma_buf == NULL) {
-        s->dma_buf = scsi_get_buf(s->current_dev, s->current_tag);
+        s->dma_buf = s->current_dev->get_buf(s->current_dev,
+                                             s->current_tag);
     }
 
     /* ??? Set SFBR to first data byte.  */
@@ -479,10 +481,10 @@ static void lsi_do_dma(LSIState *s, int 
         s->dma_buf = NULL;
         if (out) {
             /* Write the data.  */
-            scsi_write_data(s->current_dev, s->current_tag);
+            s->current_dev->write_data(s->current_dev, s->current_tag);
         } else {
             /* Request any remaining data.  */
-            scsi_read_data(s->current_dev, s->current_tag);
+            s->current_dev->read_data(s->current_dev, s->current_tag);
         }
     } else {
         s->dma_buf += count;
@@ -596,6 +598,7 @@ static void lsi_command_complete(void *o
     if (reason == SCSI_REASON_DONE) {
         DPRINTF("Command complete sense=%d\n", (int)arg);
         s->sense = arg;
+        s->command_complete = 2;
         if (s->waiting && s->dbc != 0) {
             /* Raise phase mismatch for short transfers.  */
             lsi_bad_phase(s, out, PHASE_ST);
@@ -612,6 +615,7 @@ static void lsi_command_complete(void *o
     }
     DPRINTF("Data ready tag=0x%x len=%d\n", tag, arg);
     s->current_dma_len = arg;
+    s->command_complete = 1;
     if (!s->waiting)
         return;
     if (s->waiting == 1 || s->dbc == 0) {
@@ -631,21 +635,30 @@ static void lsi_do_command(LSIState *s)
         s->dbc = 16;
     cpu_physical_memory_read(s->dnad, buf, s->dbc);
     s->sfbr = buf[0];
-    n = scsi_send_command(s->current_dev, s->current_tag, buf, s->current_lun);
+    s->command_complete = 0;
+    n = s->current_dev->send_command(s->current_dev, s->current_tag, buf,
+                                     s->current_lun);
     if (n > 0) {
         lsi_set_phase(s, PHASE_DI);
-        scsi_read_data(s->current_dev, s->current_tag);
+        s->current_dev->read_data(s->current_dev, s->current_tag);
     } else if (n < 0) {
         lsi_set_phase(s, PHASE_DO);
-        scsi_write_data(s->current_dev, s->current_tag);
+        s->current_dev->write_data(s->current_dev, s->current_tag);
     }
-    if (n && s->current_dma_len == 0) {
-        /* Command did not complete immediately so disconnect.  */
-        lsi_add_msg_byte(s, 2); /* SAVE DATA POINTER */
-        lsi_add_msg_byte(s, 4); /* DISCONNECT */
-        lsi_set_phase(s, PHASE_MI);
-        s->msg_action = 1;
-        lsi_queue_command(s);
+
+    if (!s->command_complete) {
+        if (n) {
+            /* Command did not complete immediately so disconnect.  */
+            lsi_add_msg_byte(s, 2); /* SAVE DATA POINTER */
+            lsi_add_msg_byte(s, 4); /* DISCONNECT */
+            /* wait data */
+            lsi_set_phase(s, PHASE_MI);
+            s->msg_action = 1;
+            lsi_queue_command(s);
+        } else {
+            /* wait command complete */
+            lsi_set_phase(s, PHASE_DI);
+        }
     }
 }
 
@@ -1223,6 +1236,8 @@ static uint8_t lsi_reg_readb(LSIState *s
         return s->sdid;
     case 0x07: /* GPREG0 */
         return 0x7f;
+    case 0x08: /* Revision ID */
+        return 0x00;
     case 0xa: /* SSID */
         return s->ssid;
     case 0xb: /* SBCL */
@@ -1268,6 +1283,8 @@ static uint8_t lsi_reg_readb(LSIState *s
         return s->ctest4;
     case 0x22: /* CTEST5 */
         return s->ctest5;
+    case 0x23: /* CTEST6 */
+         return 0;
     case 0x24: /* DBC[0:7] */
         return s->dbc & 0xff;
     case 0x25: /* DBC[8:15] */
@@ -1822,10 +1839,12 @@ void lsi_scsi_attach(void *opaque, Block
     }
     if (s->scsi_dev[id]) {
         DPRINTF("Destroying device %d\n", id);
-        scsi_disk_destroy(s->scsi_dev[id]);
+        s->scsi_dev[id]->destroy(s->scsi_dev[id]);
     }
     DPRINTF("Attaching block device %d\n", id);
-    s->scsi_dev[id] = scsi_disk_init(bd, 1, lsi_command_complete, s);
+    s->scsi_dev[id] = scsi_generic_init(bd, 1, lsi_command_complete, s);
+    if (s->scsi_dev[id] == NULL)
+        s->scsi_dev[id] = scsi_disk_init(bd, 1, lsi_command_complete, s);
 }
 
 void *lsi_scsi_init(PCIBus *bus, int devfn)
Index: qemu/hw/usb-msd.c
===================================================================
--- qemu.orig/hw/usb-msd.c	2007-12-06 09:28:36.000000000 +0100
+++ qemu/hw/usb-msd.c	2007-12-06 09:30:37.000000000 +0100
@@ -149,9 +149,9 @@ static void usb_msd_copy_data(MSDState *
     s->data_len -= len;
     if (s->scsi_len == 0) {
         if (s->mode == USB_MSDM_DATAIN) {
-            scsi_read_data(s->scsi_dev, s->tag);
+            s->scsi_dev->read_data(s->scsi_dev, s->tag);
         } else if (s->mode == USB_MSDM_DATAOUT) {
-            scsi_write_data(s->scsi_dev, s->tag);
+            s->scsi_dev->write_data(s->scsi_dev, s->tag);
         }
     }
 }
@@ -204,7 +204,7 @@ static void usb_msd_command_complete(voi
         return;
     }
     s->scsi_len = arg;
-    s->scsi_buf = scsi_get_buf(s->scsi_dev, tag);
+    s->scsi_buf = s->scsi_dev->get_buf(s->scsi_dev, tag);
     if (p) {
         usb_msd_copy_data(s);
         if (s->usb_len == 0) {
@@ -342,7 +342,7 @@ static int usb_msd_handle_control(USBDev
 static void usb_msd_cancel_io(USBPacket *p, void *opaque)
 {
     MSDState *s = opaque;
-    scsi_cancel_io(s->scsi_dev, s->tag);
+    s->scsi_dev->cancel_io(s->scsi_dev, s->tag);
     s->packet = NULL;
     s->scsi_len = 0;
 }
@@ -390,14 +390,14 @@ static int usb_msd_handle_data(USBDevice
             DPRINTF("Command tag 0x%x flags %08x len %d data %d\n",
                     s->tag, cbw.flags, cbw.cmd_len, s->data_len);
             s->residue = 0;
-            scsi_send_command(s->scsi_dev, s->tag, cbw.cmd, 0);
+            s->scsi_dev->send_command(s->scsi_dev, s->tag, cbw.cmd, 0);
             /* ??? Should check that USB and SCSI data transfer
                directions match.  */
             if (s->residue == 0) {
                 if (s->mode == USB_MSDM_DATAIN) {
-                    scsi_read_data(s->scsi_dev, s->tag);
+                    s->scsi_dev->read_data(s->scsi_dev, s->tag);
                 } else if (s->mode == USB_MSDM_DATAOUT) {
-                    scsi_write_data(s->scsi_dev, s->tag);
+                    s->scsi_dev->write_data(s->scsi_dev, s->tag);
                 }
             }
             ret = len;
@@ -508,7 +508,7 @@ static void usb_msd_handle_destroy(USBDe
 {
     MSDState *s = (MSDState *)dev;
 
-    scsi_disk_destroy(s->scsi_dev);
+    s->scsi_dev->destroy(s->scsi_dev);
     bdrv_delete(s->bs);
     qemu_free(s);
 }
Index: qemu/hw/scsi-generic.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ qemu/hw/scsi-generic.c	2007-12-06 14:01:15.000000000 +0100
@@ -0,0 +1,667 @@
+/*
+ * 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;
+    DPRINTF("scsi_new_request tag=0x%x\n", tag);
+    return r;
+}
+
+static void scsi_remove_request(SCSIRequest *r)
+{
+    SCSIRequest *last;
+    SCSIDeviceState *s = r->dev;
+
+    DPRINTF("scsi_remove_request tag=0x%x\n", r->tag);
+    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;
+
+    if (r != r->io_header.usr_ptr) {
+        BADF("Bad request\n");
+        exit(1);
+    }
+
+    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.dxfer_len = r->buflen;
+    r->io_header.dxferp = r->buf;
+    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 (r != r->io_header.usr_ptr) {
+        BADF("Bad request\n");
+        exit(1);
+    }
+
+    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;
+
+    if (r != r->io_header.usr_ptr) {
+        BADF("Bad request\n");
+        exit(1);
+    }
+
+    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;
+    DPRINTF("scsi_get_buf 0x%x\n", tag);
+    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_VERIFY:
+    case WRITE_6:
+    case WRITE_10:
+    case WRITE_12:
+    case WRITE_VERIFY_12:
+        *len *= blocksize;
+        break;
+    case READ_6:
+    case READ_REVERSE:
+    case RECOVER_BUFFERED_DATA:
+    case READ_10:
+    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, HARDWARE_ERROR);
+        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_memalign(512, 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, (char*)&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__ */
Index: qemu/Makefile
===================================================================
--- qemu.orig/Makefile	2007-12-06 09:28:36.000000000 +0100
+++ qemu/Makefile	2007-12-06 09:30:37.000000000 +0100
@@ -56,6 +56,7 @@ OBJS+=irq.o
 OBJS+=i2c.o smbus.o smbus_eeprom.o max7310.o max111x.o wm8750.o
 OBJS+=ssd0303.o ssd0323.o ads7846.o stellaris_input.o
 OBJS+=scsi-disk.o cdrom.o
+OBJS+=scsi-generic.o
 OBJS+=usb.o usb-hub.o usb-linux.o usb-hid.o usb-msd.o usb-wacom.o
 OBJS+=sd.o ssi-sd.o
 
Index: qemu/hw/scsi-disk.h
===================================================================
--- qemu.orig/hw/scsi-disk.h	2007-12-06 09:28:36.000000000 +0100
+++ qemu/hw/scsi-disk.h	2007-12-06 09:30:37.000000000 +0100
@@ -7,24 +7,27 @@ enum scsi_reason {
     SCSI_REASON_DATA  /* Transfer complete, more data required.  */
 };
 
+typedef struct SCSIDeviceState SCSIDeviceState;
 typedef struct SCSIDevice SCSIDevice;
 typedef void (*scsi_completionfn)(void *opaque, int reason, uint32_t tag,
                                   uint32_t arg);
 
-SCSIDevice *scsi_disk_init(BlockDriverState *bdrv,
-                           int tcq,
-                           scsi_completionfn completion,
-                           void *opaque);
-void scsi_disk_destroy(SCSIDevice *s);
+struct SCSIDevice
+{
+    SCSIDeviceState *state;
+    void (*destroy)(SCSIDevice *s);
+    int32_t (*send_command)(SCSIDevice *s, uint32_t tag, uint8_t *buf,
+                            int lun);
+    void (*read_data)(SCSIDevice *s, uint32_t tag);
+    int (*write_data)(SCSIDevice *s, uint32_t tag);
+    void (*cancel_io)(SCSIDevice *s, uint32_t tag);
+    uint8_t *(*get_buf)(SCSIDevice *s, uint32_t tag);
+};
 
-int32_t scsi_send_command(SCSIDevice *s, uint32_t tag, uint8_t *buf, int lun);
-/* SCSI data transfers are asynchrnonous.  However, unlike the block IO
-   layer the completion routine may be called directly by
-   scsi_{read,write}_data.  */
-void scsi_read_data(SCSIDevice *s, uint32_t tag);
-int scsi_write_data(SCSIDevice *s, uint32_t tag);
-void scsi_cancel_io(SCSIDevice *s, uint32_t tag);
-uint8_t *scsi_get_buf(SCSIDevice *s, uint32_t tag);
+SCSIDevice *scsi_disk_init(BlockDriverState *bdrv, int tcq,
+                           scsi_completionfn completion, void *opaque);
+SCSIDevice *scsi_generic_init(BlockDriverState *bdrv, int tcq,
+                           scsi_completionfn completion, void *opaque);
 
 /* cdrom.c */
 int cdrom_read_toc(int nb_sectors, uint8_t *buf, int msf, int start_track);

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [Qemu-devel] [PATCH v2] Real SCSI device passthrough
  2007-12-06 13:37 [Qemu-devel] [PATCH v2] Real SCSI device passthrough Laurent Vivier
@ 2007-12-06 15:30 ` Anthony Liguori
  2007-12-06 16:38   ` Laurent Vivier
  0 siblings, 1 reply; 3+ messages in thread
From: Anthony Liguori @ 2007-12-06 15:30 UTC (permalink / raw)
  To: Laurent Vivier, qemu-devel

Hi Laurent,

This patch is really neat.  I'd like to do the same with virtio-blk.

Can you separate out the general cleanups from the function of this patch?

Regards,

Anthony Liguori

Laurent Vivier wrote:
> This patch allows to connect the virtual SCSI interface of Qemu to
> a real SCSI device of the host.
> Using the devices /dev/sg, it allows to send the SCSI commands from the
> virtual SCSI interface to the real device.
>
> It has been tested with a SATA disk and an ATA CD burner with ide-scsi module 
> and wodim to burn a CD-RW.
>
> v2 improves Timeout and management of REQUEST_SENSE command.
>
> Laurent
> ---
>  Makefile          |    1 
>  block-raw.c       |   28 +-
>  block.c           |   17 +
>  block.h           |    2 
>  block_int.h       |    4 
>  hw/esp.c          |   20 -
>  hw/lsi53c895a.c   |   49 ++-
>  hw/scsi-disk.c    |   62 +++--
>  hw/scsi-disk.h    |   29 +-
>  hw/scsi-generic.c |  667 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  hw/usb-msd.c      |   16 -
>  11 files changed, 820 insertions(+), 75 deletions(-)
>
> Index: qemu/block-raw.c
> ===================================================================
> --- qemu.orig/block-raw.c	2007-12-06 09:30:27.000000000 +0100
> +++ qemu/block-raw.c	2007-12-06 09:30:37.000000000 +0100
> @@ -52,6 +52,7 @@
>  #include <sys/ioctl.h>
>  #include <linux/cdrom.h>
>  #include <linux/fd.h>
> +#include <linux/major.h>
>  #endif
>  #ifdef __FreeBSD__
>  #include <sys/disk.h>
> @@ -152,7 +153,7 @@ static int raw_pread(BlockDriverState *b
>      if (ret < 0)
>          return ret;
>  
> -    if (lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
> +    if (offset >= 0 && lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
>          ++(s->lseek_err_cnt);
>          if(s->lseek_err_cnt <= 10) {
>              DEBUG_BLOCK_PRINT("raw_pread(%d:%s, %" PRId64 ", %p, %d) [%" PRId64
> @@ -205,7 +206,7 @@ static int raw_pwrite(BlockDriverState *
>      if (ret < 0)
>          return ret;
>  
> -    if (lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
> +    if (offset >= 0 && lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
>          ++(s->lseek_err_cnt);
>          if(s->lseek_err_cnt) {
>              DEBUG_BLOCK_PRINT("raw_pwrite(%d:%s, %" PRId64 ", %p, %d) [%"
> @@ -277,8 +278,8 @@ void qemu_aio_init(void)
>             seems to fix the problem. */
>          struct aioinit ai;
>          memset(&ai, 0, sizeof(ai));
> -        ai.aio_threads = 1;
> -        ai.aio_num = 1;
> +        ai.aio_threads = 16;
> +        ai.aio_num = 16;
>          ai.aio_idle_time = 365 * 100000;
>          aio_init(&ai);
>      }
> @@ -388,7 +389,10 @@ static RawAIOCB *raw_aio_setup(BlockDriv
>      acb->aiocb.aio_sigevent.sigev_signo = aio_sig_num;
>      acb->aiocb.aio_sigevent.sigev_notify = SIGEV_SIGNAL;
>      acb->aiocb.aio_buf = buf;
> -    acb->aiocb.aio_nbytes = nb_sectors * 512;
> +    if (nb_sectors < 0)
> +        acb->aiocb.aio_nbytes = -nb_sectors;
> +    else
> +        acb->aiocb.aio_nbytes = nb_sectors * 512;
>      acb->aiocb.aio_offset = sector_num * 512;
>      acb->next = first_aio;
>      first_aio = acb;
> @@ -680,6 +684,8 @@ static int hdev_open(BlockDriverState *b
>          s->fd_open_flags = open_flags;
>          /* open will not fail even if no floppy is inserted */
>          open_flags |= O_NONBLOCK;
> +    } else if (strstart(filename, "/dev/sg", NULL)) {
> +        bs->sg = 1;
>      }
>  #endif
>      fd = open(filename, open_flags, 0644);
> @@ -859,6 +865,12 @@ static int raw_set_locked(BlockDriverSta
>      return 0;
>  }
>  
> +static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
> +{
> +    BDRVRawState *s = bs->opaque;
> +
> +    return ioctl(s->fd, req, buf);
> +}
>  #else
>  
>  static int raw_is_inserted(BlockDriverState *bs)
> @@ -881,6 +893,10 @@ static int raw_set_locked(BlockDriverSta
>      return -ENOTSUP;
>  }
>  
> +static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
> +{
> +    return -ENOTSUP;
> +}
>  #endif /* !linux */
>  
>  BlockDriver bdrv_host_device = {
> @@ -907,6 +923,8 @@ BlockDriver bdrv_host_device = {
>      .bdrv_media_changed = raw_media_changed,
>      .bdrv_eject = raw_eject,
>      .bdrv_set_locked = raw_set_locked,
> +    /* generic scsi device */
> +    .bdrv_ioctl = raw_ioctl,
>  };
>  
>  #else /* _WIN32 */
> Index: qemu/block.c
> ===================================================================
> --- qemu.orig/block.c	2007-12-06 09:30:31.000000000 +0100
> +++ qemu/block.c	2007-12-06 09:30:37.000000000 +0100
> @@ -303,7 +303,6 @@ int bdrv_file_open(BlockDriverState **pb
>  {
>      BlockDriverState *bs;
>      int ret;
> -
>      bs = bdrv_new("");
>      if (!bs)
>          return -ENOMEM;
> @@ -796,6 +795,11 @@ int bdrv_is_cached(BlockDriverState *bs)
>      return bs->cache;
>  }
>  
> +int bdrv_is_sg(BlockDriverState *bs)
> +{
> +    return bs->sg;
> +}
> +
>  /* XXX: no longer used */
>  void bdrv_set_change_cb(BlockDriverState *bs,
>                          void (*change_cb)(void *opaque), void *opaque)
> @@ -1404,3 +1408,14 @@ void bdrv_set_locked(BlockDriverState *b
>          drv->bdrv_set_locked(bs, locked);
>      }
>  }
> +
> +/* needed for generic scsi interface */
> +
> +int bdrv_ioctl(BlockDriverState *bs,  unsigned long int req, void *buf)
> +{
> +    BlockDriver *drv = bs->drv;
> +
> +    if (drv && drv->bdrv_ioctl)
> +        return drv->bdrv_ioctl(bs, req, buf);
> +    return -ENOTSUP;
> +}
> Index: qemu/block.h
> ===================================================================
> --- qemu.orig/block.h	2007-12-06 09:30:31.000000000 +0100
> +++ qemu/block.h	2007-12-06 09:30:37.000000000 +0100
> @@ -120,6 +120,7 @@ int bdrv_get_type_hint(BlockDriverState 
>  int bdrv_get_translation_hint(BlockDriverState *bs);
>  int bdrv_is_removable(BlockDriverState *bs);
>  int bdrv_is_read_only(BlockDriverState *bs);
> +int bdrv_is_sg(BlockDriverState *bs);
>  int bdrv_is_inserted(BlockDriverState *bs);
>  int bdrv_is_cached(BlockDriverState *bs);
>  int bdrv_media_changed(BlockDriverState *bs);
> @@ -150,6 +151,7 @@ int bdrv_snapshot_delete(BlockDriverStat
>  int bdrv_snapshot_list(BlockDriverState *bs,
>                         QEMUSnapshotInfo **psn_info);
>  char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn);
> +int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf);
>  
>  char *get_human_readable_size(char *buf, int buf_size, int64_t size);
>  int path_is_absolute(const char *path);
> Index: qemu/block_int.h
> ===================================================================
> --- qemu.orig/block_int.h	2007-12-06 09:30:31.000000000 +0100
> +++ qemu/block_int.h	2007-12-06 09:30:37.000000000 +0100
> @@ -82,6 +82,9 @@ struct BlockDriver {
>      int (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
>      int (*bdrv_set_locked)(BlockDriverState *bs, int locked);
>  
> +    /* to control generic scsi devices */
> +    int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, char *buf);
> +
>      BlockDriverAIOCB *free_aiocb;
>      struct BlockDriver *next;
>  };
> @@ -93,6 +96,7 @@ struct BlockDriverState {
>      int removable; /* if true, the media can be removed */
>      int locked;    /* if true, the media cannot temporarily be ejected */
>      int encrypted; /* if true, the media is encrypted */
> +    int sg;        /* if true, the device is a /dev/sg* */
>      /* event callback when inserting/removing */
>      void (*change_cb)(void *opaque);
>      void *change_opaque;
> Index: qemu/hw/scsi-disk.c
> ===================================================================
> --- qemu.orig/hw/scsi-disk.c	2007-12-06 09:30:27.000000000 +0100
> +++ qemu/hw/scsi-disk.c	2007-12-06 09:30:37.000000000 +0100
> @@ -37,7 +37,7 @@ do { fprintf(stderr, "scsi-disk: " fmt ,
>  #define SCSI_DMA_BUF_SIZE    65536
>  
>  typedef struct SCSIRequest {
> -    SCSIDevice *dev;
> +    SCSIDeviceState *dev;
>      uint32_t tag;
>      /* ??? We should probably keep track of whether the data trasfer is
>         a read or a write.  Currently we rely on the host getting it right.  */
> @@ -51,7 +51,7 @@ typedef struct SCSIRequest {
>      struct SCSIRequest *next;
>  } SCSIRequest;
>  
> -struct SCSIDevice
> +struct SCSIDeviceState
>  {
>      BlockDriverState *bdrv;
>      SCSIRequest *requests;
> @@ -69,7 +69,7 @@ struct SCSIDevice
>  /* Global pool of SCSIRequest structures.  */
>  static SCSIRequest *free_requests = NULL;
>  
> -static SCSIRequest *scsi_new_request(SCSIDevice *s, uint32_t tag)
> +static SCSIRequest *scsi_new_request(SCSIDeviceState *s, uint32_t tag)
>  {
>      SCSIRequest *r;
>  
> @@ -94,7 +94,7 @@ static SCSIRequest *scsi_new_request(SCS
>  static void scsi_remove_request(SCSIRequest *r)
>  {
>      SCSIRequest *last;
> -    SCSIDevice *s = r->dev;
> +    SCSIDeviceState *s = r->dev;
>  
>      if (s->requests == r) {
>          s->requests = r->next;
> @@ -112,7 +112,7 @@ static void scsi_remove_request(SCSIRequ
>      free_requests = r;
>  }
>  
> -static SCSIRequest *scsi_find_request(SCSIDevice *s, uint32_t tag)
> +static SCSIRequest *scsi_find_request(SCSIDeviceState *s, uint32_t tag)
>  {
>      SCSIRequest *r;
>  
> @@ -126,7 +126,7 @@ static SCSIRequest *scsi_find_request(SC
>  /* Helper function for command completion.  */
>  static void scsi_command_complete(SCSIRequest *r, int sense)
>  {
> -    SCSIDevice *s = r->dev;
> +    SCSIDeviceState *s = r->dev;
>      uint32_t tag;
>      DPRINTF("Command complete tag=0x%x sense=%d\n", r->tag, sense);
>      s->sense = sense;
> @@ -136,8 +136,9 @@ static void scsi_command_complete(SCSIRe
>  }
>  
>  /* Cancel a pending data transfer.  */
> -void scsi_cancel_io(SCSIDevice *s, uint32_t tag)
> +static void scsi_cancel_io(SCSIDevice *d, uint32_t tag)
>  {
> +    SCSIDeviceState *s = d->state;
>      SCSIRequest *r;
>      DPRINTF("Cancel tag=0x%x\n", tag);
>      r = scsi_find_request(s, tag);
> @@ -152,7 +153,7 @@ void scsi_cancel_io(SCSIDevice *s, uint3
>  static void scsi_read_complete(void * opaque, int ret)
>  {
>      SCSIRequest *r = (SCSIRequest *)opaque;
> -    SCSIDevice *s = r->dev;
> +    SCSIDeviceState *s = r->dev;
>  
>      if (ret) {
>          DPRINTF("IO error\n");
> @@ -165,8 +166,9 @@ static void scsi_read_complete(void * op
>  }
>  
>  /* Read more data from scsi device into buffer.  */
> -void scsi_read_data(SCSIDevice *s, uint32_t tag)
> +static void scsi_read_data(SCSIDevice *d, uint32_t tag)
>  {
> +    SCSIDeviceState *s = d->state;
>      SCSIRequest *r;
>      uint32_t n;
>  
> @@ -205,7 +207,7 @@ void scsi_read_data(SCSIDevice *s, uint3
>  static void scsi_write_complete(void * opaque, int ret)
>  {
>      SCSIRequest *r = (SCSIRequest *)opaque;
> -    SCSIDevice *s = r->dev;
> +    SCSIDeviceState *s = r->dev;
>      uint32_t len;
>  
>      if (ret) {
> @@ -229,8 +231,9 @@ static void scsi_write_complete(void * o
>  
>  /* Write data to a scsi device.  Returns nonzero on failure.
>     The transfer may complete asynchronously.  */
> -int scsi_write_data(SCSIDevice *s, uint32_t tag)
> +static int scsi_write_data(SCSIDevice *d, uint32_t tag)
>  {
> +    SCSIDeviceState *s = d->state;
>      SCSIRequest *r;
>      uint32_t n;
>  
> @@ -260,8 +263,9 @@ int scsi_write_data(SCSIDevice *s, uint3
>  }
>  
>  /* Return a pointer to the data buffer.  */
> -uint8_t *scsi_get_buf(SCSIDevice *s, uint32_t tag)
> +static uint8_t *scsi_get_buf(SCSIDevice *d, uint32_t tag)
>  {
> +    SCSIDeviceState *s = d->state;
>      SCSIRequest *r;
>  
>      r = scsi_find_request(s, tag);
> @@ -277,8 +281,10 @@ uint8_t *scsi_get_buf(SCSIDevice *s, uin
>     (eg. disk reads), negative for transfers to the device (eg. disk writes),
>     and zero if the command does not transfer any data.  */
>  
> -int32_t scsi_send_command(SCSIDevice *s, uint32_t tag, uint8_t *buf, int lun)
> +static int32_t scsi_send_command(SCSIDevice *d, uint32_t tag,
> +                                 uint8_t *buf, int lun)
>  {
> +    SCSIDeviceState *s = d->state;
>      int64_t nb_sectors;
>      uint32_t lba;
>      uint32_t len;
> @@ -292,7 +298,7 @@ int32_t scsi_send_command(SCSIDevice *s,
>      r = scsi_find_request(s, tag);
>      if (r) {
>          BADF("Tag 0x%x already in use\n", tag);
> -        scsi_cancel_io(s, tag);
> +        scsi_cancel_io(d, tag);
>      }
>      /* ??? Tags are not unique for different luns.  We only implement a
>         single lun, so this should not matter.  */
> @@ -577,19 +583,19 @@ int32_t scsi_send_command(SCSIDevice *s,
>      }
>  }
>  
> -void scsi_disk_destroy(SCSIDevice *s)
> +static void scsi_destroy(SCSIDevice *d)
>  {
> -    qemu_free(s);
> +    qemu_free(d->state);
> +    qemu_free(d);
>  }
>  
> -SCSIDevice *scsi_disk_init(BlockDriverState *bdrv,
> -                           int tcq,
> -                           scsi_completionfn completion,
> -                           void *opaque)
> +SCSIDevice *scsi_disk_init(BlockDriverState *bdrv, int tcq,
> +                           scsi_completionfn completion, void *opaque)
>  {
> -    SCSIDevice *s;
> +    SCSIDevice *d;
> +    SCSIDeviceState *s;
>  
> -    s = (SCSIDevice *)qemu_mallocz(sizeof(SCSIDevice));
> +    s = (SCSIDeviceState *)qemu_mallocz(sizeof(SCSIDeviceState));
>      s->bdrv = bdrv;
>      s->tcq = tcq;
>      s->completion = completion;
> @@ -600,6 +606,14 @@ SCSIDevice *scsi_disk_init(BlockDriverSt
>          s->cluster_size = 1;
>      }
>  
> -    return s;
> -}
> +    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;
> +}
> Index: qemu/hw/esp.c
> ===================================================================
> --- qemu.orig/hw/esp.c	2007-12-06 09:28:36.000000000 +0100
> +++ qemu/hw/esp.c	2007-12-06 09:30:37.000000000 +0100
> @@ -165,7 +165,7 @@ static int get_cmd(ESPState *s, uint8_t 
>  
>      if (s->current_dev) {
>          /* Started a new command before the old one finished.  Cancel it.  */
> -        scsi_cancel_io(s->current_dev, 0);
> +        s->current_dev->cancel_io(s->current_dev, 0);
>          s->async_len = 0;
>      }
>  
> @@ -188,7 +188,7 @@ static void do_cmd(ESPState *s, uint8_t 
>  
>      DPRINTF("do_cmd: busid 0x%x\n", buf[0]);
>      lun = buf[0] & 7;
> -    datalen = scsi_send_command(s->current_dev, 0, &buf[1], lun);
> +    datalen = s->current_dev->send_command(s->current_dev, 0, &buf[1], lun);
>      s->ti_size = datalen;
>      if (datalen != 0) {
>          s->rregs[ESP_RSTAT] = STAT_IN | STAT_TC;
> @@ -196,10 +196,10 @@ static void do_cmd(ESPState *s, uint8_t 
>          s->dma_counter = 0;
>          if (datalen > 0) {
>              s->rregs[ESP_RSTAT] |= STAT_DI;
> -            scsi_read_data(s->current_dev, 0);
> +            s->current_dev->read_data(s->current_dev, 0);
>          } else {
>              s->rregs[ESP_RSTAT] |= STAT_DO;
> -            scsi_write_data(s->current_dev, 0);
> +            s->current_dev->write_data(s->current_dev, 0);
>          }
>      }
>      s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
> @@ -298,9 +298,9 @@ static void esp_do_dma(ESPState *s)
>      if (s->async_len == 0) {
>          if (to_device) {
>              // ti_size is negative
> -            scsi_write_data(s->current_dev, 0);
> +            s->current_dev->write_data(s->current_dev, 0);
>          } else {
> -            scsi_read_data(s->current_dev, 0);
> +            s->current_dev->read_data(s->current_dev, 0);
>              /* If there is still data to be read from the device then
>                 complete the DMA operation immeriately.  Otherwise defer
>                 until the scsi layer has completed.  */
> @@ -335,7 +335,7 @@ static void esp_command_complete(void *o
>      } else {
>          DPRINTF("transfer %d/%d\n", s->dma_left, s->ti_size);
>          s->async_len = arg;
> -        s->async_buf = scsi_get_buf(s->current_dev, 0);
> +        s->async_buf = s->current_dev->get_buf(s->current_dev, 0);
>          if (s->dma_left) {
>              esp_do_dma(s);
>          } else if (s->dma_counter != 0 && s->ti_size <= 0) {
> @@ -611,11 +611,13 @@ void esp_scsi_attach(void *opaque, Block
>      }
>      if (s->scsi_dev[id]) {
>          DPRINTF("Destroying device %d\n", id);
> -        scsi_disk_destroy(s->scsi_dev[id]);
> +        s->scsi_dev[id]->destroy(s->scsi_dev[id]);
>      }
>      DPRINTF("Attaching block device %d\n", id);
>      /* Command queueing is not implemented.  */
> -    s->scsi_dev[id] = scsi_disk_init(bd, 0, esp_command_complete, s);
> +    s->scsi_dev[id] = scsi_generic_init(bd, 0, esp_command_complete, s);
> +    if (s->scsi_dev[id] == NULL)
> +        s->scsi_dev[id] = scsi_disk_init(bd, 0, esp_command_complete, s);
>  }
>  
>  void *esp_init(target_phys_addr_t espaddr,
> Index: qemu/hw/lsi53c895a.c
> ===================================================================
> --- qemu.orig/hw/lsi53c895a.c	2007-12-06 09:28:36.000000000 +0100
> +++ qemu/hw/lsi53c895a.c	2007-12-06 09:30:37.000000000 +0100
> @@ -187,6 +187,7 @@ typedef struct {
>      /* The tag is a combination of the device ID and the SCSI tag.  */
>      uint32_t current_tag;
>      uint32_t current_dma_len;
> +    int command_complete;
>      uint8_t *dma_buf;
>      lsi_queue *queue;
>      int queue_len;
> @@ -465,7 +466,8 @@ static void lsi_do_dma(LSIState *s, int 
>      s->dbc -= count;
>  
>      if (s->dma_buf == NULL) {
> -        s->dma_buf = scsi_get_buf(s->current_dev, s->current_tag);
> +        s->dma_buf = s->current_dev->get_buf(s->current_dev,
> +                                             s->current_tag);
>      }
>  
>      /* ??? Set SFBR to first data byte.  */
> @@ -479,10 +481,10 @@ static void lsi_do_dma(LSIState *s, int 
>          s->dma_buf = NULL;
>          if (out) {
>              /* Write the data.  */
> -            scsi_write_data(s->current_dev, s->current_tag);
> +            s->current_dev->write_data(s->current_dev, s->current_tag);
>          } else {
>              /* Request any remaining data.  */
> -            scsi_read_data(s->current_dev, s->current_tag);
> +            s->current_dev->read_data(s->current_dev, s->current_tag);
>          }
>      } else {
>          s->dma_buf += count;
> @@ -596,6 +598,7 @@ static void lsi_command_complete(void *o
>      if (reason == SCSI_REASON_DONE) {
>          DPRINTF("Command complete sense=%d\n", (int)arg);
>          s->sense = arg;
> +        s->command_complete = 2;
>          if (s->waiting && s->dbc != 0) {
>              /* Raise phase mismatch for short transfers.  */
>              lsi_bad_phase(s, out, PHASE_ST);
> @@ -612,6 +615,7 @@ static void lsi_command_complete(void *o
>      }
>      DPRINTF("Data ready tag=0x%x len=%d\n", tag, arg);
>      s->current_dma_len = arg;
> +    s->command_complete = 1;
>      if (!s->waiting)
>          return;
>      if (s->waiting == 1 || s->dbc == 0) {
> @@ -631,21 +635,30 @@ static void lsi_do_command(LSIState *s)
>          s->dbc = 16;
>      cpu_physical_memory_read(s->dnad, buf, s->dbc);
>      s->sfbr = buf[0];
> -    n = scsi_send_command(s->current_dev, s->current_tag, buf, s->current_lun);
> +    s->command_complete = 0;
> +    n = s->current_dev->send_command(s->current_dev, s->current_tag, buf,
> +                                     s->current_lun);
>      if (n > 0) {
>          lsi_set_phase(s, PHASE_DI);
> -        scsi_read_data(s->current_dev, s->current_tag);
> +        s->current_dev->read_data(s->current_dev, s->current_tag);
>      } else if (n < 0) {
>          lsi_set_phase(s, PHASE_DO);
> -        scsi_write_data(s->current_dev, s->current_tag);
> +        s->current_dev->write_data(s->current_dev, s->current_tag);
>      }
> -    if (n && s->current_dma_len == 0) {
> -        /* Command did not complete immediately so disconnect.  */
> -        lsi_add_msg_byte(s, 2); /* SAVE DATA POINTER */
> -        lsi_add_msg_byte(s, 4); /* DISCONNECT */
> -        lsi_set_phase(s, PHASE_MI);
> -        s->msg_action = 1;
> -        lsi_queue_command(s);
> +
> +    if (!s->command_complete) {
> +        if (n) {
> +            /* Command did not complete immediately so disconnect.  */
> +            lsi_add_msg_byte(s, 2); /* SAVE DATA POINTER */
> +            lsi_add_msg_byte(s, 4); /* DISCONNECT */
> +            /* wait data */
> +            lsi_set_phase(s, PHASE_MI);
> +            s->msg_action = 1;
> +            lsi_queue_command(s);
> +        } else {
> +            /* wait command complete */
> +            lsi_set_phase(s, PHASE_DI);
> +        }
>      }
>  }
>  
> @@ -1223,6 +1236,8 @@ static uint8_t lsi_reg_readb(LSIState *s
>          return s->sdid;
>      case 0x07: /* GPREG0 */
>          return 0x7f;
> +    case 0x08: /* Revision ID */
> +        return 0x00;
>      case 0xa: /* SSID */
>          return s->ssid;
>      case 0xb: /* SBCL */
> @@ -1268,6 +1283,8 @@ static uint8_t lsi_reg_readb(LSIState *s
>          return s->ctest4;
>      case 0x22: /* CTEST5 */
>          return s->ctest5;
> +    case 0x23: /* CTEST6 */
> +         return 0;
>      case 0x24: /* DBC[0:7] */
>          return s->dbc & 0xff;
>      case 0x25: /* DBC[8:15] */
> @@ -1822,10 +1839,12 @@ void lsi_scsi_attach(void *opaque, Block
>      }
>      if (s->scsi_dev[id]) {
>          DPRINTF("Destroying device %d\n", id);
> -        scsi_disk_destroy(s->scsi_dev[id]);
> +        s->scsi_dev[id]->destroy(s->scsi_dev[id]);
>      }
>      DPRINTF("Attaching block device %d\n", id);
> -    s->scsi_dev[id] = scsi_disk_init(bd, 1, lsi_command_complete, s);
> +    s->scsi_dev[id] = scsi_generic_init(bd, 1, lsi_command_complete, s);
> +    if (s->scsi_dev[id] == NULL)
> +        s->scsi_dev[id] = scsi_disk_init(bd, 1, lsi_command_complete, s);
>  }
>  
>  void *lsi_scsi_init(PCIBus *bus, int devfn)
> Index: qemu/hw/usb-msd.c
> ===================================================================
> --- qemu.orig/hw/usb-msd.c	2007-12-06 09:28:36.000000000 +0100
> +++ qemu/hw/usb-msd.c	2007-12-06 09:30:37.000000000 +0100
> @@ -149,9 +149,9 @@ static void usb_msd_copy_data(MSDState *
>      s->data_len -= len;
>      if (s->scsi_len == 0) {
>          if (s->mode == USB_MSDM_DATAIN) {
> -            scsi_read_data(s->scsi_dev, s->tag);
> +            s->scsi_dev->read_data(s->scsi_dev, s->tag);
>          } else if (s->mode == USB_MSDM_DATAOUT) {
> -            scsi_write_data(s->scsi_dev, s->tag);
> +            s->scsi_dev->write_data(s->scsi_dev, s->tag);
>          }
>      }
>  }
> @@ -204,7 +204,7 @@ static void usb_msd_command_complete(voi
>          return;
>      }
>      s->scsi_len = arg;
> -    s->scsi_buf = scsi_get_buf(s->scsi_dev, tag);
> +    s->scsi_buf = s->scsi_dev->get_buf(s->scsi_dev, tag);
>      if (p) {
>          usb_msd_copy_data(s);
>          if (s->usb_len == 0) {
> @@ -342,7 +342,7 @@ static int usb_msd_handle_control(USBDev
>  static void usb_msd_cancel_io(USBPacket *p, void *opaque)
>  {
>      MSDState *s = opaque;
> -    scsi_cancel_io(s->scsi_dev, s->tag);
> +    s->scsi_dev->cancel_io(s->scsi_dev, s->tag);
>      s->packet = NULL;
>      s->scsi_len = 0;
>  }
> @@ -390,14 +390,14 @@ static int usb_msd_handle_data(USBDevice
>              DPRINTF("Command tag 0x%x flags %08x len %d data %d\n",
>                      s->tag, cbw.flags, cbw.cmd_len, s->data_len);
>              s->residue = 0;
> -            scsi_send_command(s->scsi_dev, s->tag, cbw.cmd, 0);
> +            s->scsi_dev->send_command(s->scsi_dev, s->tag, cbw.cmd, 0);
>              /* ??? Should check that USB and SCSI data transfer
>                 directions match.  */
>              if (s->residue == 0) {
>                  if (s->mode == USB_MSDM_DATAIN) {
> -                    scsi_read_data(s->scsi_dev, s->tag);
> +                    s->scsi_dev->read_data(s->scsi_dev, s->tag);
>                  } else if (s->mode == USB_MSDM_DATAOUT) {
> -                    scsi_write_data(s->scsi_dev, s->tag);
> +                    s->scsi_dev->write_data(s->scsi_dev, s->tag);
>                  }
>              }
>              ret = len;
> @@ -508,7 +508,7 @@ static void usb_msd_handle_destroy(USBDe
>  {
>      MSDState *s = (MSDState *)dev;
>  
> -    scsi_disk_destroy(s->scsi_dev);
> +    s->scsi_dev->destroy(s->scsi_dev);
>      bdrv_delete(s->bs);
>      qemu_free(s);
>  }
> Index: qemu/hw/scsi-generic.c
> ===================================================================
> --- /dev/null	1970-01-01 00:00:00.000000000 +0000
> +++ qemu/hw/scsi-generic.c	2007-12-06 14:01:15.000000000 +0100
> @@ -0,0 +1,667 @@
> +/*
> + * 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;
> +    DPRINTF("scsi_new_request tag=0x%x\n", tag);
> +    return r;
> +}
> +
> +static void scsi_remove_request(SCSIRequest *r)
> +{
> +    SCSIRequest *last;
> +    SCSIDeviceState *s = r->dev;
> +
> +    DPRINTF("scsi_remove_request tag=0x%x\n", r->tag);
> +    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;
> +
> +    if (r != r->io_header.usr_ptr) {
> +        BADF("Bad request\n");
> +        exit(1);
> +    }
> +
> +    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.dxfer_len = r->buflen;
> +    r->io_header.dxferp = r->buf;
> +    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 (r != r->io_header.usr_ptr) {
> +        BADF("Bad request\n");
> +        exit(1);
> +    }
> +
> +    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;
> +
> +    if (r != r->io_header.usr_ptr) {
> +        BADF("Bad request\n");
> +        exit(1);
> +    }
> +
> +    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;
> +    DPRINTF("scsi_get_buf 0x%x\n", tag);
> +    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_VERIFY:
> +    case WRITE_6:
> +    case WRITE_10:
> +    case WRITE_12:
> +    case WRITE_VERIFY_12:
> +        *len *= blocksize;
> +        break;
> +    case READ_6:
> +    case READ_REVERSE:
> +    case RECOVER_BUFFERED_DATA:
> +    case READ_10:
> +    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, HARDWARE_ERROR);
> +        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_memalign(512, 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, (char*)&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__ */
> Index: qemu/Makefile
> ===================================================================
> --- qemu.orig/Makefile	2007-12-06 09:28:36.000000000 +0100
> +++ qemu/Makefile	2007-12-06 09:30:37.000000000 +0100
> @@ -56,6 +56,7 @@ OBJS+=irq.o
>  OBJS+=i2c.o smbus.o smbus_eeprom.o max7310.o max111x.o wm8750.o
>  OBJS+=ssd0303.o ssd0323.o ads7846.o stellaris_input.o
>  OBJS+=scsi-disk.o cdrom.o
> +OBJS+=scsi-generic.o
>  OBJS+=usb.o usb-hub.o usb-linux.o usb-hid.o usb-msd.o usb-wacom.o
>  OBJS+=sd.o ssi-sd.o
>  
> Index: qemu/hw/scsi-disk.h
> ===================================================================
> --- qemu.orig/hw/scsi-disk.h	2007-12-06 09:28:36.000000000 +0100
> +++ qemu/hw/scsi-disk.h	2007-12-06 09:30:37.000000000 +0100
> @@ -7,24 +7,27 @@ enum scsi_reason {
>      SCSI_REASON_DATA  /* Transfer complete, more data required.  */
>  };
>  
> +typedef struct SCSIDeviceState SCSIDeviceState;
>  typedef struct SCSIDevice SCSIDevice;
>  typedef void (*scsi_completionfn)(void *opaque, int reason, uint32_t tag,
>                                    uint32_t arg);
>  
> -SCSIDevice *scsi_disk_init(BlockDriverState *bdrv,
> -                           int tcq,
> -                           scsi_completionfn completion,
> -                           void *opaque);
> -void scsi_disk_destroy(SCSIDevice *s);
> +struct SCSIDevice
> +{
> +    SCSIDeviceState *state;
> +    void (*destroy)(SCSIDevice *s);
> +    int32_t (*send_command)(SCSIDevice *s, uint32_t tag, uint8_t *buf,
> +                            int lun);
> +    void (*read_data)(SCSIDevice *s, uint32_t tag);
> +    int (*write_data)(SCSIDevice *s, uint32_t tag);
> +    void (*cancel_io)(SCSIDevice *s, uint32_t tag);
> +    uint8_t *(*get_buf)(SCSIDevice *s, uint32_t tag);
> +};
>  
> -int32_t scsi_send_command(SCSIDevice *s, uint32_t tag, uint8_t *buf, int lun);
> -/* SCSI data transfers are asynchrnonous.  However, unlike the block IO
> -   layer the completion routine may be called directly by
> -   scsi_{read,write}_data.  */
> -void scsi_read_data(SCSIDevice *s, uint32_t tag);
> -int scsi_write_data(SCSIDevice *s, uint32_t tag);
> -void scsi_cancel_io(SCSIDevice *s, uint32_t tag);
> -uint8_t *scsi_get_buf(SCSIDevice *s, uint32_t tag);
> +SCSIDevice *scsi_disk_init(BlockDriverState *bdrv, int tcq,
> +                           scsi_completionfn completion, void *opaque);
> +SCSIDevice *scsi_generic_init(BlockDriverState *bdrv, int tcq,
> +                           scsi_completionfn completion, void *opaque);
>  
>  /* cdrom.c */
>  int cdrom_read_toc(int nb_sectors, uint8_t *buf, int msf, int start_track);
>
>
>
>
>   

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [Qemu-devel] [PATCH v2] Real SCSI device passthrough
  2007-12-06 15:30 ` Anthony Liguori
@ 2007-12-06 16:38   ` Laurent Vivier
  0 siblings, 0 replies; 3+ messages in thread
From: Laurent Vivier @ 2007-12-06 16:38 UTC (permalink / raw)
  To: Anthony Liguori; +Cc: qemu-devel

[-- Attachment #1: Type: text/plain, Size: 49870 bytes --]

Le jeudi 06 décembre 2007 à 09:30 -0600, Anthony Liguori a écrit :
> Hi Laurent,

Hi Anthony,

> This patch is really neat.  I'd like to do the same with virtio-blk.

Thank you,

> Can you separate out the general cleanups from the function of this patch?

Yes, of course. I merged all by laziness...
 
> Regards,
> 
> Anthony Liguori

Regards,
Laurent

> Laurent Vivier wrote:
> > This patch allows to connect the virtual SCSI interface of Qemu to
> > a real SCSI device of the host.
> > Using the devices /dev/sg, it allows to send the SCSI commands from the
> > virtual SCSI interface to the real device.
> >
> > It has been tested with a SATA disk and an ATA CD burner with ide-scsi module 
> > and wodim to burn a CD-RW.
> >
> > v2 improves Timeout and management of REQUEST_SENSE command.
> >
> > Laurent
> > ---
> >  Makefile          |    1 
> >  block-raw.c       |   28 +-
> >  block.c           |   17 +
> >  block.h           |    2 
> >  block_int.h       |    4 
> >  hw/esp.c          |   20 -
> >  hw/lsi53c895a.c   |   49 ++-
> >  hw/scsi-disk.c    |   62 +++--
> >  hw/scsi-disk.h    |   29 +-
> >  hw/scsi-generic.c |  667 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
> >  hw/usb-msd.c      |   16 -
> >  11 files changed, 820 insertions(+), 75 deletions(-)
> >
> > Index: qemu/block-raw.c
> > ===================================================================
> > --- qemu.orig/block-raw.c	2007-12-06 09:30:27.000000000 +0100
> > +++ qemu/block-raw.c	2007-12-06 09:30:37.000000000 +0100
> > @@ -52,6 +52,7 @@
> >  #include <sys/ioctl.h>
> >  #include <linux/cdrom.h>
> >  #include <linux/fd.h>
> > +#include <linux/major.h>
> >  #endif
> >  #ifdef __FreeBSD__
> >  #include <sys/disk.h>
> > @@ -152,7 +153,7 @@ static int raw_pread(BlockDriverState *b
> >      if (ret < 0)
> >          return ret;
> >  
> > -    if (lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
> > +    if (offset >= 0 && lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
> >          ++(s->lseek_err_cnt);
> >          if(s->lseek_err_cnt <= 10) {
> >              DEBUG_BLOCK_PRINT("raw_pread(%d:%s, %" PRId64 ", %p, %d) [%" PRId64
> > @@ -205,7 +206,7 @@ static int raw_pwrite(BlockDriverState *
> >      if (ret < 0)
> >          return ret;
> >  
> > -    if (lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
> > +    if (offset >= 0 && lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
> >          ++(s->lseek_err_cnt);
> >          if(s->lseek_err_cnt) {
> >              DEBUG_BLOCK_PRINT("raw_pwrite(%d:%s, %" PRId64 ", %p, %d) [%"
> > @@ -277,8 +278,8 @@ void qemu_aio_init(void)
> >             seems to fix the problem. */
> >          struct aioinit ai;
> >          memset(&ai, 0, sizeof(ai));
> > -        ai.aio_threads = 1;
> > -        ai.aio_num = 1;
> > +        ai.aio_threads = 16;
> > +        ai.aio_num = 16;
> >          ai.aio_idle_time = 365 * 100000;
> >          aio_init(&ai);
> >      }
> > @@ -388,7 +389,10 @@ static RawAIOCB *raw_aio_setup(BlockDriv
> >      acb->aiocb.aio_sigevent.sigev_signo = aio_sig_num;
> >      acb->aiocb.aio_sigevent.sigev_notify = SIGEV_SIGNAL;
> >      acb->aiocb.aio_buf = buf;
> > -    acb->aiocb.aio_nbytes = nb_sectors * 512;
> > +    if (nb_sectors < 0)
> > +        acb->aiocb.aio_nbytes = -nb_sectors;
> > +    else
> > +        acb->aiocb.aio_nbytes = nb_sectors * 512;
> >      acb->aiocb.aio_offset = sector_num * 512;
> >      acb->next = first_aio;
> >      first_aio = acb;
> > @@ -680,6 +684,8 @@ static int hdev_open(BlockDriverState *b
> >          s->fd_open_flags = open_flags;
> >          /* open will not fail even if no floppy is inserted */
> >          open_flags |= O_NONBLOCK;
> > +    } else if (strstart(filename, "/dev/sg", NULL)) {
> > +        bs->sg = 1;
> >      }
> >  #endif
> >      fd = open(filename, open_flags, 0644);
> > @@ -859,6 +865,12 @@ static int raw_set_locked(BlockDriverSta
> >      return 0;
> >  }
> >  
> > +static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
> > +{
> > +    BDRVRawState *s = bs->opaque;
> > +
> > +    return ioctl(s->fd, req, buf);
> > +}
> >  #else
> >  
> >  static int raw_is_inserted(BlockDriverState *bs)
> > @@ -881,6 +893,10 @@ static int raw_set_locked(BlockDriverSta
> >      return -ENOTSUP;
> >  }
> >  
> > +static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
> > +{
> > +    return -ENOTSUP;
> > +}
> >  #endif /* !linux */
> >  
> >  BlockDriver bdrv_host_device = {
> > @@ -907,6 +923,8 @@ BlockDriver bdrv_host_device = {
> >      .bdrv_media_changed = raw_media_changed,
> >      .bdrv_eject = raw_eject,
> >      .bdrv_set_locked = raw_set_locked,
> > +    /* generic scsi device */
> > +    .bdrv_ioctl = raw_ioctl,
> >  };
> >  
> >  #else /* _WIN32 */
> > Index: qemu/block.c
> > ===================================================================
> > --- qemu.orig/block.c	2007-12-06 09:30:31.000000000 +0100
> > +++ qemu/block.c	2007-12-06 09:30:37.000000000 +0100
> > @@ -303,7 +303,6 @@ int bdrv_file_open(BlockDriverState **pb
> >  {
> >      BlockDriverState *bs;
> >      int ret;
> > -
> >      bs = bdrv_new("");
> >      if (!bs)
> >          return -ENOMEM;
> > @@ -796,6 +795,11 @@ int bdrv_is_cached(BlockDriverState *bs)
> >      return bs->cache;
> >  }
> >  
> > +int bdrv_is_sg(BlockDriverState *bs)
> > +{
> > +    return bs->sg;
> > +}
> > +
> >  /* XXX: no longer used */
> >  void bdrv_set_change_cb(BlockDriverState *bs,
> >                          void (*change_cb)(void *opaque), void *opaque)
> > @@ -1404,3 +1408,14 @@ void bdrv_set_locked(BlockDriverState *b
> >          drv->bdrv_set_locked(bs, locked);
> >      }
> >  }
> > +
> > +/* needed for generic scsi interface */
> > +
> > +int bdrv_ioctl(BlockDriverState *bs,  unsigned long int req, void *buf)
> > +{
> > +    BlockDriver *drv = bs->drv;
> > +
> > +    if (drv && drv->bdrv_ioctl)
> > +        return drv->bdrv_ioctl(bs, req, buf);
> > +    return -ENOTSUP;
> > +}
> > Index: qemu/block.h
> > ===================================================================
> > --- qemu.orig/block.h	2007-12-06 09:30:31.000000000 +0100
> > +++ qemu/block.h	2007-12-06 09:30:37.000000000 +0100
> > @@ -120,6 +120,7 @@ int bdrv_get_type_hint(BlockDriverState 
> >  int bdrv_get_translation_hint(BlockDriverState *bs);
> >  int bdrv_is_removable(BlockDriverState *bs);
> >  int bdrv_is_read_only(BlockDriverState *bs);
> > +int bdrv_is_sg(BlockDriverState *bs);
> >  int bdrv_is_inserted(BlockDriverState *bs);
> >  int bdrv_is_cached(BlockDriverState *bs);
> >  int bdrv_media_changed(BlockDriverState *bs);
> > @@ -150,6 +151,7 @@ int bdrv_snapshot_delete(BlockDriverStat
> >  int bdrv_snapshot_list(BlockDriverState *bs,
> >                         QEMUSnapshotInfo **psn_info);
> >  char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn);
> > +int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf);
> >  
> >  char *get_human_readable_size(char *buf, int buf_size, int64_t size);
> >  int path_is_absolute(const char *path);
> > Index: qemu/block_int.h
> > ===================================================================
> > --- qemu.orig/block_int.h	2007-12-06 09:30:31.000000000 +0100
> > +++ qemu/block_int.h	2007-12-06 09:30:37.000000000 +0100
> > @@ -82,6 +82,9 @@ struct BlockDriver {
> >      int (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
> >      int (*bdrv_set_locked)(BlockDriverState *bs, int locked);
> >  
> > +    /* to control generic scsi devices */
> > +    int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, char *buf);
> > +
> >      BlockDriverAIOCB *free_aiocb;
> >      struct BlockDriver *next;
> >  };
> > @@ -93,6 +96,7 @@ struct BlockDriverState {
> >      int removable; /* if true, the media can be removed */
> >      int locked;    /* if true, the media cannot temporarily be ejected */
> >      int encrypted; /* if true, the media is encrypted */
> > +    int sg;        /* if true, the device is a /dev/sg* */
> >      /* event callback when inserting/removing */
> >      void (*change_cb)(void *opaque);
> >      void *change_opaque;
> > Index: qemu/hw/scsi-disk.c
> > ===================================================================
> > --- qemu.orig/hw/scsi-disk.c	2007-12-06 09:30:27.000000000 +0100
> > +++ qemu/hw/scsi-disk.c	2007-12-06 09:30:37.000000000 +0100
> > @@ -37,7 +37,7 @@ do { fprintf(stderr, "scsi-disk: " fmt ,
> >  #define SCSI_DMA_BUF_SIZE    65536
> >  
> >  typedef struct SCSIRequest {
> > -    SCSIDevice *dev;
> > +    SCSIDeviceState *dev;
> >      uint32_t tag;
> >      /* ??? We should probably keep track of whether the data trasfer is
> >         a read or a write.  Currently we rely on the host getting it right.  */
> > @@ -51,7 +51,7 @@ typedef struct SCSIRequest {
> >      struct SCSIRequest *next;
> >  } SCSIRequest;
> >  
> > -struct SCSIDevice
> > +struct SCSIDeviceState
> >  {
> >      BlockDriverState *bdrv;
> >      SCSIRequest *requests;
> > @@ -69,7 +69,7 @@ struct SCSIDevice
> >  /* Global pool of SCSIRequest structures.  */
> >  static SCSIRequest *free_requests = NULL;
> >  
> > -static SCSIRequest *scsi_new_request(SCSIDevice *s, uint32_t tag)
> > +static SCSIRequest *scsi_new_request(SCSIDeviceState *s, uint32_t tag)
> >  {
> >      SCSIRequest *r;
> >  
> > @@ -94,7 +94,7 @@ static SCSIRequest *scsi_new_request(SCS
> >  static void scsi_remove_request(SCSIRequest *r)
> >  {
> >      SCSIRequest *last;
> > -    SCSIDevice *s = r->dev;
> > +    SCSIDeviceState *s = r->dev;
> >  
> >      if (s->requests == r) {
> >          s->requests = r->next;
> > @@ -112,7 +112,7 @@ static void scsi_remove_request(SCSIRequ
> >      free_requests = r;
> >  }
> >  
> > -static SCSIRequest *scsi_find_request(SCSIDevice *s, uint32_t tag)
> > +static SCSIRequest *scsi_find_request(SCSIDeviceState *s, uint32_t tag)
> >  {
> >      SCSIRequest *r;
> >  
> > @@ -126,7 +126,7 @@ static SCSIRequest *scsi_find_request(SC
> >  /* Helper function for command completion.  */
> >  static void scsi_command_complete(SCSIRequest *r, int sense)
> >  {
> > -    SCSIDevice *s = r->dev;
> > +    SCSIDeviceState *s = r->dev;
> >      uint32_t tag;
> >      DPRINTF("Command complete tag=0x%x sense=%d\n", r->tag, sense);
> >      s->sense = sense;
> > @@ -136,8 +136,9 @@ static void scsi_command_complete(SCSIRe
> >  }
> >  
> >  /* Cancel a pending data transfer.  */
> > -void scsi_cancel_io(SCSIDevice *s, uint32_t tag)
> > +static void scsi_cancel_io(SCSIDevice *d, uint32_t tag)
> >  {
> > +    SCSIDeviceState *s = d->state;
> >      SCSIRequest *r;
> >      DPRINTF("Cancel tag=0x%x\n", tag);
> >      r = scsi_find_request(s, tag);
> > @@ -152,7 +153,7 @@ void scsi_cancel_io(SCSIDevice *s, uint3
> >  static void scsi_read_complete(void * opaque, int ret)
> >  {
> >      SCSIRequest *r = (SCSIRequest *)opaque;
> > -    SCSIDevice *s = r->dev;
> > +    SCSIDeviceState *s = r->dev;
> >  
> >      if (ret) {
> >          DPRINTF("IO error\n");
> > @@ -165,8 +166,9 @@ static void scsi_read_complete(void * op
> >  }
> >  
> >  /* Read more data from scsi device into buffer.  */
> > -void scsi_read_data(SCSIDevice *s, uint32_t tag)
> > +static void scsi_read_data(SCSIDevice *d, uint32_t tag)
> >  {
> > +    SCSIDeviceState *s = d->state;
> >      SCSIRequest *r;
> >      uint32_t n;
> >  
> > @@ -205,7 +207,7 @@ void scsi_read_data(SCSIDevice *s, uint3
> >  static void scsi_write_complete(void * opaque, int ret)
> >  {
> >      SCSIRequest *r = (SCSIRequest *)opaque;
> > -    SCSIDevice *s = r->dev;
> > +    SCSIDeviceState *s = r->dev;
> >      uint32_t len;
> >  
> >      if (ret) {
> > @@ -229,8 +231,9 @@ static void scsi_write_complete(void * o
> >  
> >  /* Write data to a scsi device.  Returns nonzero on failure.
> >     The transfer may complete asynchronously.  */
> > -int scsi_write_data(SCSIDevice *s, uint32_t tag)
> > +static int scsi_write_data(SCSIDevice *d, uint32_t tag)
> >  {
> > +    SCSIDeviceState *s = d->state;
> >      SCSIRequest *r;
> >      uint32_t n;
> >  
> > @@ -260,8 +263,9 @@ int scsi_write_data(SCSIDevice *s, uint3
> >  }
> >  
> >  /* Return a pointer to the data buffer.  */
> > -uint8_t *scsi_get_buf(SCSIDevice *s, uint32_t tag)
> > +static uint8_t *scsi_get_buf(SCSIDevice *d, uint32_t tag)
> >  {
> > +    SCSIDeviceState *s = d->state;
> >      SCSIRequest *r;
> >  
> >      r = scsi_find_request(s, tag);
> > @@ -277,8 +281,10 @@ uint8_t *scsi_get_buf(SCSIDevice *s, uin
> >     (eg. disk reads), negative for transfers to the device (eg. disk writes),
> >     and zero if the command does not transfer any data.  */
> >  
> > -int32_t scsi_send_command(SCSIDevice *s, uint32_t tag, uint8_t *buf, int lun)
> > +static int32_t scsi_send_command(SCSIDevice *d, uint32_t tag,
> > +                                 uint8_t *buf, int lun)
> >  {
> > +    SCSIDeviceState *s = d->state;
> >      int64_t nb_sectors;
> >      uint32_t lba;
> >      uint32_t len;
> > @@ -292,7 +298,7 @@ int32_t scsi_send_command(SCSIDevice *s,
> >      r = scsi_find_request(s, tag);
> >      if (r) {
> >          BADF("Tag 0x%x already in use\n", tag);
> > -        scsi_cancel_io(s, tag);
> > +        scsi_cancel_io(d, tag);
> >      }
> >      /* ??? Tags are not unique for different luns.  We only implement a
> >         single lun, so this should not matter.  */
> > @@ -577,19 +583,19 @@ int32_t scsi_send_command(SCSIDevice *s,
> >      }
> >  }
> >  
> > -void scsi_disk_destroy(SCSIDevice *s)
> > +static void scsi_destroy(SCSIDevice *d)
> >  {
> > -    qemu_free(s);
> > +    qemu_free(d->state);
> > +    qemu_free(d);
> >  }
> >  
> > -SCSIDevice *scsi_disk_init(BlockDriverState *bdrv,
> > -                           int tcq,
> > -                           scsi_completionfn completion,
> > -                           void *opaque)
> > +SCSIDevice *scsi_disk_init(BlockDriverState *bdrv, int tcq,
> > +                           scsi_completionfn completion, void *opaque)
> >  {
> > -    SCSIDevice *s;
> > +    SCSIDevice *d;
> > +    SCSIDeviceState *s;
> >  
> > -    s = (SCSIDevice *)qemu_mallocz(sizeof(SCSIDevice));
> > +    s = (SCSIDeviceState *)qemu_mallocz(sizeof(SCSIDeviceState));
> >      s->bdrv = bdrv;
> >      s->tcq = tcq;
> >      s->completion = completion;
> > @@ -600,6 +606,14 @@ SCSIDevice *scsi_disk_init(BlockDriverSt
> >          s->cluster_size = 1;
> >      }
> >  
> > -    return s;
> > -}
> > +    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;
> > +}
> > Index: qemu/hw/esp.c
> > ===================================================================
> > --- qemu.orig/hw/esp.c	2007-12-06 09:28:36.000000000 +0100
> > +++ qemu/hw/esp.c	2007-12-06 09:30:37.000000000 +0100
> > @@ -165,7 +165,7 @@ static int get_cmd(ESPState *s, uint8_t 
> >  
> >      if (s->current_dev) {
> >          /* Started a new command before the old one finished.  Cancel it.  */
> > -        scsi_cancel_io(s->current_dev, 0);
> > +        s->current_dev->cancel_io(s->current_dev, 0);
> >          s->async_len = 0;
> >      }
> >  
> > @@ -188,7 +188,7 @@ static void do_cmd(ESPState *s, uint8_t 
> >  
> >      DPRINTF("do_cmd: busid 0x%x\n", buf[0]);
> >      lun = buf[0] & 7;
> > -    datalen = scsi_send_command(s->current_dev, 0, &buf[1], lun);
> > +    datalen = s->current_dev->send_command(s->current_dev, 0, &buf[1], lun);
> >      s->ti_size = datalen;
> >      if (datalen != 0) {
> >          s->rregs[ESP_RSTAT] = STAT_IN | STAT_TC;
> > @@ -196,10 +196,10 @@ static void do_cmd(ESPState *s, uint8_t 
> >          s->dma_counter = 0;
> >          if (datalen > 0) {
> >              s->rregs[ESP_RSTAT] |= STAT_DI;
> > -            scsi_read_data(s->current_dev, 0);
> > +            s->current_dev->read_data(s->current_dev, 0);
> >          } else {
> >              s->rregs[ESP_RSTAT] |= STAT_DO;
> > -            scsi_write_data(s->current_dev, 0);
> > +            s->current_dev->write_data(s->current_dev, 0);
> >          }
> >      }
> >      s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
> > @@ -298,9 +298,9 @@ static void esp_do_dma(ESPState *s)
> >      if (s->async_len == 0) {
> >          if (to_device) {
> >              // ti_size is negative
> > -            scsi_write_data(s->current_dev, 0);
> > +            s->current_dev->write_data(s->current_dev, 0);
> >          } else {
> > -            scsi_read_data(s->current_dev, 0);
> > +            s->current_dev->read_data(s->current_dev, 0);
> >              /* If there is still data to be read from the device then
> >                 complete the DMA operation immeriately.  Otherwise defer
> >                 until the scsi layer has completed.  */
> > @@ -335,7 +335,7 @@ static void esp_command_complete(void *o
> >      } else {
> >          DPRINTF("transfer %d/%d\n", s->dma_left, s->ti_size);
> >          s->async_len = arg;
> > -        s->async_buf = scsi_get_buf(s->current_dev, 0);
> > +        s->async_buf = s->current_dev->get_buf(s->current_dev, 0);
> >          if (s->dma_left) {
> >              esp_do_dma(s);
> >          } else if (s->dma_counter != 0 && s->ti_size <= 0) {
> > @@ -611,11 +611,13 @@ void esp_scsi_attach(void *opaque, Block
> >      }
> >      if (s->scsi_dev[id]) {
> >          DPRINTF("Destroying device %d\n", id);
> > -        scsi_disk_destroy(s->scsi_dev[id]);
> > +        s->scsi_dev[id]->destroy(s->scsi_dev[id]);
> >      }
> >      DPRINTF("Attaching block device %d\n", id);
> >      /* Command queueing is not implemented.  */
> > -    s->scsi_dev[id] = scsi_disk_init(bd, 0, esp_command_complete, s);
> > +    s->scsi_dev[id] = scsi_generic_init(bd, 0, esp_command_complete, s);
> > +    if (s->scsi_dev[id] == NULL)
> > +        s->scsi_dev[id] = scsi_disk_init(bd, 0, esp_command_complete, s);
> >  }
> >  
> >  void *esp_init(target_phys_addr_t espaddr,
> > Index: qemu/hw/lsi53c895a.c
> > ===================================================================
> > --- qemu.orig/hw/lsi53c895a.c	2007-12-06 09:28:36.000000000 +0100
> > +++ qemu/hw/lsi53c895a.c	2007-12-06 09:30:37.000000000 +0100
> > @@ -187,6 +187,7 @@ typedef struct {
> >      /* The tag is a combination of the device ID and the SCSI tag.  */
> >      uint32_t current_tag;
> >      uint32_t current_dma_len;
> > +    int command_complete;
> >      uint8_t *dma_buf;
> >      lsi_queue *queue;
> >      int queue_len;
> > @@ -465,7 +466,8 @@ static void lsi_do_dma(LSIState *s, int 
> >      s->dbc -= count;
> >  
> >      if (s->dma_buf == NULL) {
> > -        s->dma_buf = scsi_get_buf(s->current_dev, s->current_tag);
> > +        s->dma_buf = s->current_dev->get_buf(s->current_dev,
> > +                                             s->current_tag);
> >      }
> >  
> >      /* ??? Set SFBR to first data byte.  */
> > @@ -479,10 +481,10 @@ static void lsi_do_dma(LSIState *s, int 
> >          s->dma_buf = NULL;
> >          if (out) {
> >              /* Write the data.  */
> > -            scsi_write_data(s->current_dev, s->current_tag);
> > +            s->current_dev->write_data(s->current_dev, s->current_tag);
> >          } else {
> >              /* Request any remaining data.  */
> > -            scsi_read_data(s->current_dev, s->current_tag);
> > +            s->current_dev->read_data(s->current_dev, s->current_tag);
> >          }
> >      } else {
> >          s->dma_buf += count;
> > @@ -596,6 +598,7 @@ static void lsi_command_complete(void *o
> >      if (reason == SCSI_REASON_DONE) {
> >          DPRINTF("Command complete sense=%d\n", (int)arg);
> >          s->sense = arg;
> > +        s->command_complete = 2;
> >          if (s->waiting && s->dbc != 0) {
> >              /* Raise phase mismatch for short transfers.  */
> >              lsi_bad_phase(s, out, PHASE_ST);
> > @@ -612,6 +615,7 @@ static void lsi_command_complete(void *o
> >      }
> >      DPRINTF("Data ready tag=0x%x len=%d\n", tag, arg);
> >      s->current_dma_len = arg;
> > +    s->command_complete = 1;
> >      if (!s->waiting)
> >          return;
> >      if (s->waiting == 1 || s->dbc == 0) {
> > @@ -631,21 +635,30 @@ static void lsi_do_command(LSIState *s)
> >          s->dbc = 16;
> >      cpu_physical_memory_read(s->dnad, buf, s->dbc);
> >      s->sfbr = buf[0];
> > -    n = scsi_send_command(s->current_dev, s->current_tag, buf, s->current_lun);
> > +    s->command_complete = 0;
> > +    n = s->current_dev->send_command(s->current_dev, s->current_tag, buf,
> > +                                     s->current_lun);
> >      if (n > 0) {
> >          lsi_set_phase(s, PHASE_DI);
> > -        scsi_read_data(s->current_dev, s->current_tag);
> > +        s->current_dev->read_data(s->current_dev, s->current_tag);
> >      } else if (n < 0) {
> >          lsi_set_phase(s, PHASE_DO);
> > -        scsi_write_data(s->current_dev, s->current_tag);
> > +        s->current_dev->write_data(s->current_dev, s->current_tag);
> >      }
> > -    if (n && s->current_dma_len == 0) {
> > -        /* Command did not complete immediately so disconnect.  */
> > -        lsi_add_msg_byte(s, 2); /* SAVE DATA POINTER */
> > -        lsi_add_msg_byte(s, 4); /* DISCONNECT */
> > -        lsi_set_phase(s, PHASE_MI);
> > -        s->msg_action = 1;
> > -        lsi_queue_command(s);
> > +
> > +    if (!s->command_complete) {
> > +        if (n) {
> > +            /* Command did not complete immediately so disconnect.  */
> > +            lsi_add_msg_byte(s, 2); /* SAVE DATA POINTER */
> > +            lsi_add_msg_byte(s, 4); /* DISCONNECT */
> > +            /* wait data */
> > +            lsi_set_phase(s, PHASE_MI);
> > +            s->msg_action = 1;
> > +            lsi_queue_command(s);
> > +        } else {
> > +            /* wait command complete */
> > +            lsi_set_phase(s, PHASE_DI);
> > +        }
> >      }
> >  }
> >  
> > @@ -1223,6 +1236,8 @@ static uint8_t lsi_reg_readb(LSIState *s
> >          return s->sdid;
> >      case 0x07: /* GPREG0 */
> >          return 0x7f;
> > +    case 0x08: /* Revision ID */
> > +        return 0x00;
> >      case 0xa: /* SSID */
> >          return s->ssid;
> >      case 0xb: /* SBCL */
> > @@ -1268,6 +1283,8 @@ static uint8_t lsi_reg_readb(LSIState *s
> >          return s->ctest4;
> >      case 0x22: /* CTEST5 */
> >          return s->ctest5;
> > +    case 0x23: /* CTEST6 */
> > +         return 0;
> >      case 0x24: /* DBC[0:7] */
> >          return s->dbc & 0xff;
> >      case 0x25: /* DBC[8:15] */
> > @@ -1822,10 +1839,12 @@ void lsi_scsi_attach(void *opaque, Block
> >      }
> >      if (s->scsi_dev[id]) {
> >          DPRINTF("Destroying device %d\n", id);
> > -        scsi_disk_destroy(s->scsi_dev[id]);
> > +        s->scsi_dev[id]->destroy(s->scsi_dev[id]);
> >      }
> >      DPRINTF("Attaching block device %d\n", id);
> > -    s->scsi_dev[id] = scsi_disk_init(bd, 1, lsi_command_complete, s);
> > +    s->scsi_dev[id] = scsi_generic_init(bd, 1, lsi_command_complete, s);
> > +    if (s->scsi_dev[id] == NULL)
> > +        s->scsi_dev[id] = scsi_disk_init(bd, 1, lsi_command_complete, s);
> >  }
> >  
> >  void *lsi_scsi_init(PCIBus *bus, int devfn)
> > Index: qemu/hw/usb-msd.c
> > ===================================================================
> > --- qemu.orig/hw/usb-msd.c	2007-12-06 09:28:36.000000000 +0100
> > +++ qemu/hw/usb-msd.c	2007-12-06 09:30:37.000000000 +0100
> > @@ -149,9 +149,9 @@ static void usb_msd_copy_data(MSDState *
> >      s->data_len -= len;
> >      if (s->scsi_len == 0) {
> >          if (s->mode == USB_MSDM_DATAIN) {
> > -            scsi_read_data(s->scsi_dev, s->tag);
> > +            s->scsi_dev->read_data(s->scsi_dev, s->tag);
> >          } else if (s->mode == USB_MSDM_DATAOUT) {
> > -            scsi_write_data(s->scsi_dev, s->tag);
> > +            s->scsi_dev->write_data(s->scsi_dev, s->tag);
> >          }
> >      }
> >  }
> > @@ -204,7 +204,7 @@ static void usb_msd_command_complete(voi
> >          return;
> >      }
> >      s->scsi_len = arg;
> > -    s->scsi_buf = scsi_get_buf(s->scsi_dev, tag);
> > +    s->scsi_buf = s->scsi_dev->get_buf(s->scsi_dev, tag);
> >      if (p) {
> >          usb_msd_copy_data(s);
> >          if (s->usb_len == 0) {
> > @@ -342,7 +342,7 @@ static int usb_msd_handle_control(USBDev
> >  static void usb_msd_cancel_io(USBPacket *p, void *opaque)
> >  {
> >      MSDState *s = opaque;
> > -    scsi_cancel_io(s->scsi_dev, s->tag);
> > +    s->scsi_dev->cancel_io(s->scsi_dev, s->tag);
> >      s->packet = NULL;
> >      s->scsi_len = 0;
> >  }
> > @@ -390,14 +390,14 @@ static int usb_msd_handle_data(USBDevice
> >              DPRINTF("Command tag 0x%x flags %08x len %d data %d\n",
> >                      s->tag, cbw.flags, cbw.cmd_len, s->data_len);
> >              s->residue = 0;
> > -            scsi_send_command(s->scsi_dev, s->tag, cbw.cmd, 0);
> > +            s->scsi_dev->send_command(s->scsi_dev, s->tag, cbw.cmd, 0);
> >              /* ??? Should check that USB and SCSI data transfer
> >                 directions match.  */
> >              if (s->residue == 0) {
> >                  if (s->mode == USB_MSDM_DATAIN) {
> > -                    scsi_read_data(s->scsi_dev, s->tag);
> > +                    s->scsi_dev->read_data(s->scsi_dev, s->tag);
> >                  } else if (s->mode == USB_MSDM_DATAOUT) {
> > -                    scsi_write_data(s->scsi_dev, s->tag);
> > +                    s->scsi_dev->write_data(s->scsi_dev, s->tag);
> >                  }
> >              }
> >              ret = len;
> > @@ -508,7 +508,7 @@ static void usb_msd_handle_destroy(USBDe
> >  {
> >      MSDState *s = (MSDState *)dev;
> >  
> > -    scsi_disk_destroy(s->scsi_dev);
> > +    s->scsi_dev->destroy(s->scsi_dev);
> >      bdrv_delete(s->bs);
> >      qemu_free(s);
> >  }
> > Index: qemu/hw/scsi-generic.c
> > ===================================================================
> > --- /dev/null	1970-01-01 00:00:00.000000000 +0000
> > +++ qemu/hw/scsi-generic.c	2007-12-06 14:01:15.000000000 +0100
> > @@ -0,0 +1,667 @@
> > +/*
> > + * 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;
> > +    DPRINTF("scsi_new_request tag=0x%x\n", tag);
> > +    return r;
> > +}
> > +
> > +static void scsi_remove_request(SCSIRequest *r)
> > +{
> > +    SCSIRequest *last;
> > +    SCSIDeviceState *s = r->dev;
> > +
> > +    DPRINTF("scsi_remove_request tag=0x%x\n", r->tag);
> > +    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;
> > +
> > +    if (r != r->io_header.usr_ptr) {
> > +        BADF("Bad request\n");
> > +        exit(1);
> > +    }
> > +
> > +    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.dxfer_len = r->buflen;
> > +    r->io_header.dxferp = r->buf;
> > +    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 (r != r->io_header.usr_ptr) {
> > +        BADF("Bad request\n");
> > +        exit(1);
> > +    }
> > +
> > +    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;
> > +
> > +    if (r != r->io_header.usr_ptr) {
> > +        BADF("Bad request\n");
> > +        exit(1);
> > +    }
> > +
> > +    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;
> > +    DPRINTF("scsi_get_buf 0x%x\n", tag);
> > +    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_VERIFY:
> > +    case WRITE_6:
> > +    case WRITE_10:
> > +    case WRITE_12:
> > +    case WRITE_VERIFY_12:
> > +        *len *= blocksize;
> > +        break;
> > +    case READ_6:
> > +    case READ_REVERSE:
> > +    case RECOVER_BUFFERED_DATA:
> > +    case READ_10:
> > +    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, HARDWARE_ERROR);
> > +        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_memalign(512, 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, (char*)&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__ */
> > Index: qemu/Makefile
> > ===================================================================
> > --- qemu.orig/Makefile	2007-12-06 09:28:36.000000000 +0100
> > +++ qemu/Makefile	2007-12-06 09:30:37.000000000 +0100
> > @@ -56,6 +56,7 @@ OBJS+=irq.o
> >  OBJS+=i2c.o smbus.o smbus_eeprom.o max7310.o max111x.o wm8750.o
> >  OBJS+=ssd0303.o ssd0323.o ads7846.o stellaris_input.o
> >  OBJS+=scsi-disk.o cdrom.o
> > +OBJS+=scsi-generic.o
> >  OBJS+=usb.o usb-hub.o usb-linux.o usb-hid.o usb-msd.o usb-wacom.o
> >  OBJS+=sd.o ssi-sd.o
> >  
> > Index: qemu/hw/scsi-disk.h
> > ===================================================================
> > --- qemu.orig/hw/scsi-disk.h	2007-12-06 09:28:36.000000000 +0100
> > +++ qemu/hw/scsi-disk.h	2007-12-06 09:30:37.000000000 +0100
> > @@ -7,24 +7,27 @@ enum scsi_reason {
> >      SCSI_REASON_DATA  /* Transfer complete, more data required.  */
> >  };
> >  
> > +typedef struct SCSIDeviceState SCSIDeviceState;
> >  typedef struct SCSIDevice SCSIDevice;
> >  typedef void (*scsi_completionfn)(void *opaque, int reason, uint32_t tag,
> >                                    uint32_t arg);
> >  
> > -SCSIDevice *scsi_disk_init(BlockDriverState *bdrv,
> > -                           int tcq,
> > -                           scsi_completionfn completion,
> > -                           void *opaque);
> > -void scsi_disk_destroy(SCSIDevice *s);
> > +struct SCSIDevice
> > +{
> > +    SCSIDeviceState *state;
> > +    void (*destroy)(SCSIDevice *s);
> > +    int32_t (*send_command)(SCSIDevice *s, uint32_t tag, uint8_t *buf,
> > +                            int lun);
> > +    void (*read_data)(SCSIDevice *s, uint32_t tag);
> > +    int (*write_data)(SCSIDevice *s, uint32_t tag);
> > +    void (*cancel_io)(SCSIDevice *s, uint32_t tag);
> > +    uint8_t *(*get_buf)(SCSIDevice *s, uint32_t tag);
> > +};
> >  
> > -int32_t scsi_send_command(SCSIDevice *s, uint32_t tag, uint8_t *buf, int lun);
> > -/* SCSI data transfers are asynchrnonous.  However, unlike the block IO
> > -   layer the completion routine may be called directly by
> > -   scsi_{read,write}_data.  */
> > -void scsi_read_data(SCSIDevice *s, uint32_t tag);
> > -int scsi_write_data(SCSIDevice *s, uint32_t tag);
> > -void scsi_cancel_io(SCSIDevice *s, uint32_t tag);
> > -uint8_t *scsi_get_buf(SCSIDevice *s, uint32_t tag);
> > +SCSIDevice *scsi_disk_init(BlockDriverState *bdrv, int tcq,
> > +                           scsi_completionfn completion, void *opaque);
> > +SCSIDevice *scsi_generic_init(BlockDriverState *bdrv, int tcq,
> > +                           scsi_completionfn completion, void *opaque);
> >  
> >  /* cdrom.c */
> >  int cdrom_read_toc(int nb_sectors, uint8_t *buf, int msf, int start_track);
> >
> >
> >
> >
> >   
> 
-- 
------------- Laurent.Vivier@bull.net  --------------
       "Any sufficiently advanced technology is
  indistinguishable from magic." - Arthur C. Clarke

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Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2007-12-06 13:37 [Qemu-devel] [PATCH v2] Real SCSI device passthrough Laurent Vivier
2007-12-06 15:30 ` Anthony Liguori
2007-12-06 16:38   ` Laurent Vivier

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