[Qemu-devel] [PULL 0/5] SCSI changes for 2013-07-17

[Qemu-devel] [PULL 0/5] SCSI changes for 2013-07-17

[Paolo Bonzini]

Anthony,

The following changes since commit 6453a3a69488196f26d12654c6b148446abdf3d6:

  Merge remote-tracking branch 'quintela/migration.next' into staging (2013-07-15 14:49:16 -0500)

are available in the git repository at:

  git://github.com/bonzini/qemu.git scsi-next

for you to fetch changes up to 0777b5dde42f4f453abc8bb2c4e145fb8749415d:

  iscsi: factor out sector conversions (2013-07-17 17:01:41 +0200)

A bunch of block/iscsi.c fixes, almost all CCed to qemu-stable.

Paolo
----------------------------------------------------------------
Peter Lieven (4):
      iscsi: fix -ENOSPC in iscsi_create()
      iscsi: remove support for misaligned nb_sectors in aio_readv
      iscsi: assert that sectors are aligned to LUN blocksize
      iscsi: factor out sector conversions

Ronnie Sahlberg (1):
      Fix iSCSI crash on SG_IO with an iovector

 block/iscsi.c | 104 ++++++++++++++++++++++++++++++++++++++++++----------------
 1 file changed, 76 insertions(+), 28 deletions(-)
-- 
1.8.1.4

[Qemu-devel] [PULL 1/5] Fix iSCSI crash on SG_IO with an iovector

[Paolo Bonzini]

From: Ronnie Sahlberg <ronniesahlberg@gmail.com>

Don't assume that SG_IO is always invoked with a simple buffer,
check the iovec_count and if it is >= 1 then we need to pass an array
of iovectors to libiscsi instead of just a plain buffer.

Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 block/iscsi.c | 51 ++++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 44 insertions(+), 7 deletions(-)

diff --git a/block/iscsi.c b/block/iscsi.c
index 0bbf0b1..fa5252c 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -32,6 +32,7 @@
 #include "block/block_int.h"
 #include "trace.h"
 #include "block/scsi.h"
+#include "qemu/iov.h"
 
 #include <iscsi/iscsi.h>
 #include <iscsi/scsi-lowlevel.h>
@@ -651,6 +652,9 @@ iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
 {
     IscsiAIOCB *acb = opaque;
 
+    g_free(acb->buf);
+    acb->buf = NULL;
+
     if (acb->canceled != 0) {
         return;
     }
@@ -727,14 +731,30 @@ static BlockDriverAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
     memcpy(&acb->task->cdb[0], acb->ioh->cmdp, acb->ioh->cmd_len);
     acb->task->expxferlen = acb->ioh->dxfer_len;
 
+    data.size = 0;
     if (acb->task->xfer_dir == SCSI_XFER_WRITE) {
-        data.data = acb->ioh->dxferp;
-        data.size = acb->ioh->dxfer_len;
+        if (acb->ioh->iovec_count == 0) {
+            data.data = acb->ioh->dxferp;
+            data.size = acb->ioh->dxfer_len;
+        } else {
+#if defined(LIBISCSI_FEATURE_IOVECTOR)
+            scsi_task_set_iov_out(acb->task,
+                                 (struct scsi_iovec *) acb->ioh->dxferp,
+                                 acb->ioh->iovec_count);
+#else
+            struct iovec *iov = (struct iovec *)acb->ioh->dxferp;
+
+            acb->buf = g_malloc(acb->ioh->dxfer_len);
+            data.data = acb->buf;
+            data.size = iov_to_buf(iov, acb->ioh->iovec_count, 0,
+                                   acb->buf, acb->ioh->dxfer_len);
+#endif
+        }
     }
+
     if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
                                  iscsi_aio_ioctl_cb,
-                                 (acb->task->xfer_dir == SCSI_XFER_WRITE) ?
-                                     &data : NULL,
+                                 (data.size > 0) ? &data : NULL,
                                  acb) != 0) {
         scsi_free_scsi_task(acb->task);
         qemu_aio_release(acb);
@@ -743,9 +763,26 @@ static BlockDriverAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
 
     /* tell libiscsi to read straight into the buffer we got from ioctl */
     if (acb->task->xfer_dir == SCSI_XFER_READ) {
-        scsi_task_add_data_in_buffer(acb->task,
-                                     acb->ioh->dxfer_len,
-                                     acb->ioh->dxferp);
+        if (acb->ioh->iovec_count == 0) {
+            scsi_task_add_data_in_buffer(acb->task,
+                                         acb->ioh->dxfer_len,
+                                         acb->ioh->dxferp);
+        } else {
+#if defined(LIBISCSI_FEATURE_IOVECTOR)
+            scsi_task_set_iov_in(acb->task,
+                                 (struct scsi_iovec *) acb->ioh->dxferp,
+                                 acb->ioh->iovec_count);
+#else
+            int i;
+            for (i = 0; i < acb->ioh->iovec_count; i++) {
+                struct iovec *iov = (struct iovec *)acb->ioh->dxferp;
+
+                scsi_task_add_data_in_buffer(acb->task,
+                    iov[i].iov_len,
+                    iov[i].iov_base);
+            }
+#endif
+        }
     }
 
     iscsi_set_events(iscsilun);
-- 
1.8.1.4

[Qemu-devel] [PULL 2/5] iscsi: fix -ENOSPC in iscsi_create()

[Paolo Bonzini]

From: Peter Lieven <pl@kamp.de>

the -ENOPSC case did not work due to the missing goto.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 block/iscsi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/block/iscsi.c b/block/iscsi.c
index fa5252c..91b602c 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -1272,6 +1272,7 @@ static int iscsi_create(const char *filename, QEMUOptionParameter *options)
     }
     if (bs.total_sectors < total_size) {
         ret = -ENOSPC;
+        goto out;
     }
 
     ret = 0;
-- 
1.8.1.4

[Qemu-devel] [PULL 3/5] iscsi: remove support for misaligned nb_sectors in aio_readv

[Paolo Bonzini]

From: Peter Lieven <pl@kamp.de>

this hask is not working (anymore). support for misaligned offsets should
be handled at the block layer.

Signed-off-by: Peter Lieven <pl@kamp.de>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 block/iscsi.c | 22 ++++------------------
 1 file changed, 4 insertions(+), 18 deletions(-)

diff --git a/block/iscsi.c b/block/iscsi.c
index 91b602c..df283ed 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -62,8 +62,6 @@ typedef struct IscsiAIOCB {
     int status;
     int canceled;
     int retries;
-    size_t read_size;
-    size_t read_offset;
     int64_t sector_num;
     int nb_sectors;
 #ifdef __linux__
@@ -380,6 +378,7 @@ static int
 iscsi_aio_readv_acb(IscsiAIOCB *acb)
 {
     struct iscsi_context *iscsi = acb->iscsilun->iscsi;
+    size_t size;
     uint64_t lba;
     uint32_t num_sectors;
     int ret;
@@ -392,20 +391,7 @@ iscsi_aio_readv_acb(IscsiAIOCB *acb)
     acb->status      = -EINPROGRESS;
     acb->buf         = NULL;
 
-    /* If LUN blocksize is bigger than BDRV_BLOCK_SIZE a read from QEMU
-     * may be misaligned to the LUN, so we may need to read some extra
-     * data.
-     */
-    acb->read_offset = 0;
-    if (acb->iscsilun->block_size > BDRV_SECTOR_SIZE) {
-        uint64_t bdrv_offset = BDRV_SECTOR_SIZE * acb->sector_num;
-
-        acb->read_offset  = bdrv_offset % acb->iscsilun->block_size;
-    }
-
-    num_sectors  = (acb->read_size + acb->iscsilun->block_size
-                    + acb->read_offset - 1)
-                    / acb->iscsilun->block_size;
+    size = acb->nb_sectors * BDRV_SECTOR_SIZE;
 
     acb->task = malloc(sizeof(struct scsi_task));
     if (acb->task == NULL) {
@@ -416,8 +402,9 @@ iscsi_aio_readv_acb(IscsiAIOCB *acb)
     memset(acb->task, 0, sizeof(struct scsi_task));
 
     acb->task->xfer_dir = SCSI_XFER_READ;
+    acb->task->expxferlen = size;
     lba = sector_qemu2lun(acb->sector_num, acb->iscsilun);
-    acb->task->expxferlen = acb->read_size;
+    num_sectors = sector_qemu2lun(acb->nb_sectors, acb->iscsilun);
 
     switch (acb->iscsilun->type) {
     case TYPE_DISK:
@@ -472,7 +459,6 @@ iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num,
     acb->sector_num  = sector_num;
     acb->iscsilun    = iscsilun;
     acb->qiov        = qiov;
-    acb->read_size   = BDRV_SECTOR_SIZE * (size_t)acb->nb_sectors;
     acb->retries     = ISCSI_CMD_RETRIES;
 
     if (iscsi_aio_readv_acb(acb) != 0) {
-- 
1.8.1.4

[Qemu-devel] [PULL 4/5] iscsi: assert that sectors are aligned to LUN blocksize

[Paolo Bonzini]

From: Peter Lieven <pl@kamp.de>

if the blocksize of an iSCSI LUN is bigger than the BDRV_SECTOR_SIZE
it is possible that sector_num or nb_sectors are not correctly
aligned.

to avoid corruption we fail requests which are misaligned.

Signed-off-by: Peter Lieven <pl@kamp.de>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 block/iscsi.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/block/iscsi.c b/block/iscsi.c
index df283ed..1294fdf 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -237,6 +237,18 @@ static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
     return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
 }
 
+static bool is_request_lun_aligned(int64_t sector_num, int nb_sectors,
+                                      IscsiLun *iscsilun)
+{
+    if ((sector_num * BDRV_SECTOR_SIZE) % iscsilun->block_size ||
+        (nb_sectors * BDRV_SECTOR_SIZE) % iscsilun->block_size) {
+            error_report("iSCSI misaligned request: iscsilun->block_size %u, sector_num %ld, nb_sectors %d",
+                         iscsilun->block_size, sector_num, nb_sectors);
+            return 0;
+    }
+    return 1;
+}
+
 static int
 iscsi_aio_writev_acb(IscsiAIOCB *acb)
 {
@@ -321,6 +333,10 @@ iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num,
     IscsiLun *iscsilun = bs->opaque;
     IscsiAIOCB *acb;
 
+    if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
+        return NULL;
+    }
+
     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
     trace_iscsi_aio_writev(iscsilun->iscsi, sector_num, nb_sectors, opaque, acb);
 
@@ -452,6 +468,10 @@ iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num,
     IscsiLun *iscsilun = bs->opaque;
     IscsiAIOCB *acb;
 
+    if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
+        return NULL;
+    }
+
     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
     trace_iscsi_aio_readv(iscsilun->iscsi, sector_num, nb_sectors, opaque, acb);
 
-- 
1.8.1.4

[Qemu-devel] [PULL 5/5] iscsi: factor out sector conversions

[Paolo Bonzini]

From: Peter Lieven <pl@kamp.de>

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 block/iscsi.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/block/iscsi.c b/block/iscsi.c
index 1294fdf..5f28c6a 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -232,6 +232,11 @@ iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status,
     iscsi_schedule_bh(acb);
 }
 
+static int64_t sector_lun2qemu(int64_t sector, IscsiLun *iscsilun)
+{
+    return sector * iscsilun->block_size / BDRV_SECTOR_SIZE;
+}
+
 static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
 {
     return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
@@ -296,7 +301,7 @@ iscsi_aio_writev_acb(IscsiAIOCB *acb)
     lba = sector_qemu2lun(acb->sector_num, acb->iscsilun);
     *(uint32_t *)&acb->task->cdb[2]  = htonl(lba >> 32);
     *(uint32_t *)&acb->task->cdb[6]  = htonl(lba & 0xffffffff);
-    num_sectors = size / acb->iscsilun->block_size;
+    num_sectors = sector_qemu2lun(acb->nb_sectors, acb->iscsilun);
     *(uint32_t *)&acb->task->cdb[10] = htonl(num_sectors);
     acb->task->expxferlen = size;
 
@@ -1161,8 +1166,7 @@ static int iscsi_open(BlockDriverState *bs, QDict *options, int flags)
     if ((ret = iscsi_readcapacity_sync(iscsilun)) != 0) {
         goto out;
     }
-    bs->total_sectors    = iscsilun->num_blocks *
-                           iscsilun->block_size / BDRV_SECTOR_SIZE ;
+    bs->total_sectors = sector_lun2qemu(iscsilun->num_blocks, iscsilun);
 
     /* Medium changer or tape. We dont have any emulation for this so this must
      * be sg ioctl compatible. We force it to be sg, otherwise qemu will try
-- 
1.8.1.4