Patchwork [RFC,04/19] block: rename buffer_alignment to guest_block_size

login
register
mail settings
Submitter Kevin Wolf
Date Dec. 6, 2013, 5:22 p.m.
Message ID <1386350580-5666-5-git-send-email-kwolf@redhat.com>
Download mbox | patch
Permalink /patch/298145/
State New
Headers show

Comments

Kevin Wolf - Dec. 6, 2013, 5:22 p.m.
From: Paolo Bonzini <pbonzini@redhat.com>

The alignment field is now set to the value that is promised to the
guest, rather than required by the host.  The next patches will make
QEMU aware of the host-provided values, so make this clear.

The alignment is also not about memory buffers, but about the sectors on
the disk, change the documentation of the field.

At this point, the field is set by the device emulation, but completely
ignored by the block layer.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block.c                   | 10 +++++-----
 hw/block/virtio-blk.c     |  2 +-
 hw/ide/core.c             |  2 +-
 hw/scsi/scsi-disk.c       |  2 +-
 hw/scsi/scsi-generic.c    |  2 +-
 include/block/block.h     |  2 +-
 include/block/block_int.h |  4 ++--
 7 files changed, 12 insertions(+), 12 deletions(-)
Wayne Xia - Dec. 10, 2013, 3:25 a.m.
Cool to have a separation of emulator/block concepts.

Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>

Patch

diff --git a/block.c b/block.c
index 669793b..34fedf0 100644
--- a/block.c
+++ b/block.c
@@ -788,7 +788,7 @@  static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
     }
 
     bs->open_flags = flags;
-    bs->buffer_alignment = 512;
+    bs->guest_block_size = 512;
     bs->zero_beyond_eof = true;
     open_flags = bdrv_open_flags(bs, flags);
     bs->read_only = !(open_flags & BDRV_O_RDWR);
@@ -1625,7 +1625,7 @@  static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
     bs_dest->dev_ops            = bs_src->dev_ops;
     bs_dest->dev_opaque         = bs_src->dev_opaque;
     bs_dest->dev                = bs_src->dev;
-    bs_dest->buffer_alignment   = bs_src->buffer_alignment;
+    bs_dest->guest_block_size   = bs_src->guest_block_size;
     bs_dest->copy_on_read       = bs_src->copy_on_read;
 
     bs_dest->enable_write_cache = bs_src->enable_write_cache;
@@ -1776,7 +1776,7 @@  void bdrv_detach_dev(BlockDriverState *bs, void *dev)
     bs->dev = NULL;
     bs->dev_ops = NULL;
     bs->dev_opaque = NULL;
-    bs->buffer_alignment = 512;
+    bs->guest_block_size = 512;
 }
 
 /* TODO change to return DeviceState * when all users are qdevified */
@@ -4353,9 +4353,9 @@  BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
     return NULL;
 }
 
-void bdrv_set_buffer_alignment(BlockDriverState *bs, int align)
+void bdrv_set_guest_block_size(BlockDriverState *bs, int align)
 {
-    bs->buffer_alignment = align;
+    bs->guest_block_size = align;
 }
 
 void *qemu_blockalign(BlockDriverState *bs, size_t size)
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index 13f6d82..323e9ec 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -720,7 +720,7 @@  static int virtio_blk_device_init(VirtIODevice *vdev)
     register_savevm(qdev, "virtio-blk", virtio_blk_id++, 2,
                     virtio_blk_save, virtio_blk_load, s);
     bdrv_set_dev_ops(s->bs, &virtio_block_ops, s);
-    bdrv_set_buffer_alignment(s->bs, s->conf->logical_block_size);
+    bdrv_set_guest_block_size(s->bs, s->conf->logical_block_size);
 
     bdrv_iostatus_enable(s->bs);
 
diff --git a/hw/ide/core.c b/hw/ide/core.c
index e1f4c33..036cd4a 100644
--- a/hw/ide/core.c
+++ b/hw/ide/core.c
@@ -2103,7 +2103,7 @@  int ide_init_drive(IDEState *s, BlockDriverState *bs, IDEDriveKind kind,
     s->smart_selftest_count = 0;
     if (kind == IDE_CD) {
         bdrv_set_dev_ops(bs, &ide_cd_block_ops, s);
-        bdrv_set_buffer_alignment(bs, 2048);
+        bdrv_set_guest_block_size(bs, 2048);
     } else {
         if (!bdrv_is_inserted(s->bs)) {
             error_report("Device needs media, but drive is empty");
diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c
index 74e6a14..1043a5f 100644
--- a/hw/scsi/scsi-disk.c
+++ b/hw/scsi/scsi-disk.c
@@ -2117,7 +2117,7 @@  static int scsi_initfn(SCSIDevice *dev)
     } else {
         bdrv_set_dev_ops(s->qdev.conf.bs, &scsi_disk_block_ops, s);
     }
-    bdrv_set_buffer_alignment(s->qdev.conf.bs, s->qdev.blocksize);
+    bdrv_set_guest_block_size(s->qdev.conf.bs, s->qdev.blocksize);
 
     bdrv_iostatus_enable(s->qdev.conf.bs);
     add_boot_device_path(s->qdev.conf.bootindex, &dev->qdev, NULL);
diff --git a/hw/scsi/scsi-generic.c b/hw/scsi/scsi-generic.c
index 8f195be..f08b64e 100644
--- a/hw/scsi/scsi-generic.c
+++ b/hw/scsi/scsi-generic.c
@@ -210,7 +210,7 @@  static void scsi_read_complete(void * opaque, int ret)
             s->blocksize = ldl_be_p(&r->buf[8]);
             s->max_lba = ldq_be_p(&r->buf[0]);
         }
-        bdrv_set_buffer_alignment(s->conf.bs, s->blocksize);
+        bdrv_set_guest_block_size(s->conf.bs, s->blocksize);
 
         scsi_req_data(&r->req, len);
         if (!r->req.io_canceled) {
diff --git a/include/block/block.h b/include/block/block.h
index d262c0e..564c1c3 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -384,7 +384,7 @@  void bdrv_img_create(const char *filename, const char *fmt,
                      Error **errp, bool quiet);
 
 size_t bdrv_opt_mem_align(BlockDriverState *bs);
-void bdrv_set_buffer_alignment(BlockDriverState *bs, int align);
+void bdrv_set_guest_block_size(BlockDriverState *bs, int align);
 void *qemu_blockalign(BlockDriverState *bs, size_t size);
 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);
 
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 6a84f83..760cfc5 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -293,8 +293,8 @@  struct BlockDriverState {
     /* Whether produces zeros when read beyond eof */
     bool zero_beyond_eof;
 
-    /* the memory alignment required for the buffers handled by this driver */
-    int buffer_alignment;
+    /* the block size for which the guest device expects atomicity */
+    int guest_block_size;
 
     /* do we need to tell the quest if we have a volatile write cache? */
     int enable_write_cache;