[PATCH v7 2/8] block: consolidate blocksize properties consistency checks

[Roman Kagan <rvkagan@yandex-team.ru>]

Several block device properties related to blocksize configuration must
be in certain relationship WRT each other: physical block must be no
smaller than logical block; min_io_size, opt_io_size, and
discard_granularity must be a multiple of a logical block.

To ensure these requirements are met, add corresponding consistency
checks to blkconf_blocksizes, adjusting its signature to communicate
possible error to the caller.  Also remove the now redundant consistency
checks from the specific devices.

Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
---
v5 -> v6:
- fix forgotten xen-block and swim

v4 -> v5:
- fix/reword error messages [Philippe, Kevin]
- do early return on failed consistency check [Philippe]
- use QEMU_IS_ALIGNED instead of open coding [Philippe]

 include/hw/block/block.h   |  2 +-
 hw/block/block.c           | 30 +++++++++++++++++++++++++++++-
 hw/block/fdc.c             |  5 ++++-
 hw/block/nvme.c            |  5 ++++-
 hw/block/swim.c            |  5 ++++-
 hw/block/virtio-blk.c      |  7 +------
 hw/block/xen-block.c       |  6 +-----
 hw/ide/qdev.c              |  5 ++++-
 hw/scsi/scsi-disk.c        | 12 +++++-------
 hw/usb/dev-storage.c       |  5 ++++-
 tests/qemu-iotests/172.out |  2 +-
 11 files changed, 58 insertions(+), 26 deletions(-)

diff --git a/include/hw/block/block.h b/include/hw/block/block.h
index d7246f3862..784953a237 100644
--- a/include/hw/block/block.h
+++ b/include/hw/block/block.h
@@ -87,7 +87,7 @@ bool blk_check_size_and_read_all(BlockBackend *blk, void *buf, hwaddr size,
 bool blkconf_geometry(BlockConf *conf, int *trans,
                       unsigned cyls_max, unsigned heads_max, unsigned secs_max,
                       Error **errp);
-void blkconf_blocksizes(BlockConf *conf);
+bool blkconf_blocksizes(BlockConf *conf, Error **errp);
 bool blkconf_apply_backend_options(BlockConf *conf, bool readonly,
                                    bool resizable, Error **errp);
 
diff --git a/hw/block/block.c b/hw/block/block.c
index bf56c7612b..b22207c921 100644
--- a/hw/block/block.c
+++ b/hw/block/block.c
@@ -61,7 +61,7 @@ bool blk_check_size_and_read_all(BlockBackend *blk, void *buf, hwaddr size,
     return true;
 }
 
-void blkconf_blocksizes(BlockConf *conf)
+bool blkconf_blocksizes(BlockConf *conf, Error **errp)
 {
     BlockBackend *blk = conf->blk;
     BlockSizes blocksizes;
@@ -83,6 +83,34 @@ void blkconf_blocksizes(BlockConf *conf)
             conf->logical_block_size = BDRV_SECTOR_SIZE;
         }
     }
+
+    if (conf->logical_block_size > conf->physical_block_size) {
+        error_setg(errp,
+                   "logical_block_size > physical_block_size not supported");
+        return false;
+    }
+
+    if (!QEMU_IS_ALIGNED(conf->min_io_size, conf->logical_block_size)) {
+        error_setg(errp,
+                   "min_io_size must be a multiple of logical_block_size");
+        return false;
+    }
+
+    if (!QEMU_IS_ALIGNED(conf->opt_io_size, conf->logical_block_size)) {
+        error_setg(errp,
+                   "opt_io_size must be a multiple of logical_block_size");
+        return false;
+    }
+
+    if (conf->discard_granularity != -1 &&
+        !QEMU_IS_ALIGNED(conf->discard_granularity,
+                         conf->logical_block_size)) {
+        error_setg(errp, "discard_granularity must be "
+                   "a multiple of logical_block_size");
+        return false;
+    }
+
+    return true;
 }
 
 bool blkconf_apply_backend_options(BlockConf *conf, bool readonly,
diff --git a/hw/block/fdc.c b/hw/block/fdc.c
index c5fb9d6ece..8eda572ef4 100644
--- a/hw/block/fdc.c
+++ b/hw/block/fdc.c
@@ -554,7 +554,10 @@ static void floppy_drive_realize(DeviceState *qdev, Error **errp)
         read_only = !blk_bs(dev->conf.blk) || blk_is_read_only(dev->conf.blk);
     }
 
-    blkconf_blocksizes(&dev->conf);
+    if (!blkconf_blocksizes(&dev->conf, errp)) {
+        return;
+    }
+
     if (dev->conf.logical_block_size != 512 ||
         dev->conf.physical_block_size != 512)
     {
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 2f3100e56c..672650e162 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -1390,7 +1390,10 @@ static void nvme_realize(PCIDevice *pci_dev, Error **errp)
         host_memory_backend_set_mapped(n->pmrdev, true);
     }
 
-    blkconf_blocksizes(&n->conf);
+    if (!blkconf_blocksizes(&n->conf, errp)) {
+        return;
+    }
+
     if (!blkconf_apply_backend_options(&n->conf, blk_is_read_only(n->conf.blk),
                                        false, errp)) {
         return;
diff --git a/hw/block/swim.c b/hw/block/swim.c
index 8f124782f4..74f56e8f46 100644
--- a/hw/block/swim.c
+++ b/hw/block/swim.c
@@ -189,7 +189,10 @@ static void swim_drive_realize(DeviceState *qdev, Error **errp)
         assert(ret == 0);
     }
 
-    blkconf_blocksizes(&dev->conf);
+    if (!blkconf_blocksizes(&dev->conf, errp)) {
+        return;
+    }
+
     if (dev->conf.logical_block_size != 512 ||
         dev->conf.physical_block_size != 512)
     {
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index 413083e62f..4ffdb130be 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -1162,12 +1162,7 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
         return;
     }
 
-    blkconf_blocksizes(&conf->conf);
-
-    if (conf->conf.logical_block_size >
-        conf->conf.physical_block_size) {
-        error_setg(errp,
-                   "logical_block_size > physical_block_size not supported");
+    if (!blkconf_blocksizes(&conf->conf, errp)) {
         return;
     }
 
diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c
index 570489d6d9..e17fec50e1 100644
--- a/hw/block/xen-block.c
+++ b/hw/block/xen-block.c
@@ -239,11 +239,7 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
         return;
     }
 
-    blkconf_blocksizes(conf);
-
-    if (conf->logical_block_size > conf->physical_block_size) {
-        error_setg(
-            errp, "logical_block_size > physical_block_size not supported");
+    if (!blkconf_blocksizes(conf, errp)) {
         return;
     }
 
diff --git a/hw/ide/qdev.c b/hw/ide/qdev.c
index 06b11583f5..b4821b2403 100644
--- a/hw/ide/qdev.c
+++ b/hw/ide/qdev.c
@@ -187,7 +187,10 @@ static void ide_dev_initfn(IDEDevice *dev, IDEDriveKind kind, Error **errp)
         return;
     }
 
-    blkconf_blocksizes(&dev->conf);
+    if (!blkconf_blocksizes(&dev->conf, errp)) {
+        return;
+    }
+
     if (dev->conf.logical_block_size != 512) {
         error_setg(errp, "logical_block_size must be 512 for IDE");
         return;
diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c
index 387503e11b..8ce68a9dd6 100644
--- a/hw/scsi/scsi-disk.c
+++ b/hw/scsi/scsi-disk.c
@@ -2346,12 +2346,7 @@ static void scsi_realize(SCSIDevice *dev, Error **errp)
         return;
     }
 
-    blkconf_blocksizes(&s->qdev.conf);
-
-    if (s->qdev.conf.logical_block_size >
-        s->qdev.conf.physical_block_size) {
-        error_setg(errp,
-                   "logical_block_size > physical_block_size not supported");
+    if (!blkconf_blocksizes(&s->qdev.conf, errp)) {
         return;
     }
 
@@ -2436,7 +2431,9 @@ static void scsi_hd_realize(SCSIDevice *dev, Error **errp)
     if (s->qdev.conf.blk) {
         ctx = blk_get_aio_context(s->qdev.conf.blk);
         aio_context_acquire(ctx);
-        blkconf_blocksizes(&s->qdev.conf);
+        if (!blkconf_blocksizes(&s->qdev.conf, errp)) {
+            goto out;
+        }
     }
     s->qdev.blocksize = s->qdev.conf.logical_block_size;
     s->qdev.type = TYPE_DISK;
@@ -2444,6 +2441,7 @@ static void scsi_hd_realize(SCSIDevice *dev, Error **errp)
         s->product = g_strdup("QEMU HARDDISK");
     }
     scsi_realize(&s->qdev, errp);
+out:
     if (ctx) {
         aio_context_release(ctx);
     }
diff --git a/hw/usb/dev-storage.c b/hw/usb/dev-storage.c
index 4eba47538d..de461f37bd 100644
--- a/hw/usb/dev-storage.c
+++ b/hw/usb/dev-storage.c
@@ -599,7 +599,10 @@ static void usb_msd_storage_realize(USBDevice *dev, Error **errp)
         return;
     }
 
-    blkconf_blocksizes(&s->conf);
+    if (!blkconf_blocksizes(&s->conf, errp)) {
+        return;
+    }
+
     if (!blkconf_apply_backend_options(&s->conf, blk_is_read_only(blk), true,
                                        errp)) {
         return;
diff --git a/tests/qemu-iotests/172.out b/tests/qemu-iotests/172.out
index 7abbe82427..59cc70aebb 100644
--- a/tests/qemu-iotests/172.out
+++ b/tests/qemu-iotests/172.out
@@ -1204,7 +1204,7 @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,physica
                 drive-type = "144"
 
 Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,logical_block_size=4096
-QEMU_PROG: -device floppy,drive=none0,logical_block_size=4096: Physical and logical block size must be 512 for floppy
+QEMU_PROG: -device floppy,drive=none0,logical_block_size=4096: logical_block_size > physical_block_size not supported
 
 Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,physical_block_size=1024
 QEMU_PROG: -device floppy,drive=none0,physical_block_size=1024: Physical and logical block size must be 512 for floppy
-- 
2.26.2