[Qemu-devel] Fwd: [PATCH v2 2/6] geometry: Detect blocksize via ioctls in separate static functions

[Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>]

copying to mail list


-------- Forwarded Message --------
Subject: [PATCH v2 2/6] geometry: Detect blocksize via ioctls in 
separate static functions
Date: Tue, 18 Nov 2014 17:09:57 +0100
From: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
To: armbru@redhat.com, pbonzini@redhat.com, stefanha@redhat.com, 
kwolf@redhat.com
CC: borntraeger@de.ibm.com, cornelia.huck@de.ibm.com, 
dahi@linux.vnet.ibm.com, mihajlov@linux.vnet.ibm.com, Ekaterina Tumanova 
<tumanova@linux.vnet.ibm.com>

Move the IOCTL calls that detect logical blocksize from raw_probe_alignment
into separate function (probe_logical_blocksize).
Introduce function which detect physical blocksize via IOCTL
(probe_physical_blocksize).
Both functions will be used in the next patch.

Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
---
  block/raw-posix.c | 58 
+++++++++++++++++++++++++++++++++++++------------------
  1 file changed, 39 insertions(+), 19 deletions(-)

diff --git a/block/raw-posix.c b/block/raw-posix.c
index e100ae2..45f1d79 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -223,50 +223,70 @@ static int raw_normalize_devicepath(const char 
**filename)
  }
  #endif

-static void raw_probe_alignment(BlockDriverState *bs, int fd, Error **errp)
+static unsigned int probe_logical_blocksize(BlockDriverState *bs, int fd)
  {
-    BDRVRawState *s = bs->opaque;
-    char *buf;
-    unsigned int sector_size;
-
-    /* For /dev/sg devices the alignment is not really used.
-       With buffered I/O, we don't have any restrictions. */
-    if (bs->sg || !s->needs_alignment) {
-        bs->request_alignment = 1;
-        s->buf_align = 1;
-        return;
-    }
+    unsigned int sector_size = 0;

      /* Try a few ioctls to get the right size */
-    bs->request_alignment = 0;
-    s->buf_align = 0;
-
  #ifdef BLKSSZGET
      if (ioctl(fd, BLKSSZGET, &sector_size) >= 0) {
-        bs->request_alignment = sector_size;
+        return sector_size;
      }
  #endif
  #ifdef DKIOCGETBLOCKSIZE
      if (ioctl(fd, DKIOCGETBLOCKSIZE, &sector_size) >= 0) {
-        bs->request_alignment = sector_size;
+        return sector_size;
      }
  #endif
  #ifdef DIOCGSECTORSIZE
      if (ioctl(fd, DIOCGSECTORSIZE, &sector_size) >= 0) {
-        bs->request_alignment = sector_size;
+        return sector_size;
      }
  #endif
  #ifdef CONFIG_XFS
      if (s->is_xfs) {
          struct dioattr da;
          if (xfsctl(NULL, fd, XFS_IOC_DIOINFO, &da) >= 0) {
-            bs->request_alignment = da.d_miniosz;
+            sector_size = da.d_miniosz;
              /* The kernel returns wrong information for d_mem */
              /* s->buf_align = da.d_mem; */
+            return sector_size;
          }
      }
  #endif

+    return 0;
+}
+
+static unsigned int probe_physical_blocksize(BlockDriverState *bs, int fd)
+{
+    unsigned int blk_size = 0;
+#ifdef BLKPBSZGET
+    if (ioctl(fd, BLKPBSZGET, &blk_size) >= 0) {
+        return blk_size;
+    }
+#endif
+
+    return 0;
+}
+
+static void raw_probe_alignment(BlockDriverState *bs, int fd, Error **errp)
+{
+    BDRVRawState *s = bs->opaque;
+    char *buf;
+
+    /* For /dev/sg devices the alignment is not really used.
+       With buffered I/O, we don't have any restrictions. */
+    if (bs->sg || !s->needs_alignment) {
+        bs->request_alignment = 1;
+        s->buf_align = 1;
+        return;
+    }
+
+    s->buf_align = 0;
+    /* Let's try to use the logical blocksize for the alignment. */
+    bs->request_alignment = probe_logical_blocksize(bs, fd);
+
      /* If we could not get the sizes so far, we can only guess them */
      if (!s->buf_align) {
          size_t align;
-- 
1.8.5.5