Ren Mingxin
2012-Apr-10 07:28 UTC
[PATCH] virtio_blk: Add help function to format mass of disks
The current virtio block's naming algorithm just supports 18278
(26^3 + 26^2 + 26) disks. If there are mass of virtio blocks,
there will be disks with the same name.
Based on commit 3e1a7ff8a0a7b948f2684930166954f9e8e776fe, I add
function "virtblk_name_format()" for virtio block to support mass
of disks naming.
Signed-off-by: Ren Mingxin <renmx at cn.fujitsu.com>
---
drivers/block/virtio_blk.c | 38 ++++++++++++++++++++++++++------------
1 files changed, 26 insertions(+), 12 deletions(-)
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index c4a60ba..86516c8 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -374,6 +374,31 @@ static int init_vq(struct virtio_blk *vblk)
return err;
}
+static int virtblk_name_format(char *prefix, int index, char *buf, int buflen)
+{
+ const int base = 'z' - 'a' + 1;
+ char *begin = buf + strlen(prefix);
+ char *begin = buf + strlen(prefix);
+ char *end = buf + buflen;
+ char *p;
+ int unit;
+
+ p = end - 1;
+ *p = '\0';
+ unit = base;
+ do {
+ if (p == begin)
+ return -EINVAL;
+ *--p = 'a' + (index % unit);
+ index = (index / unit) - 1;
+ } while (index >= 0);
+
+ memmove(begin, p, end - p);
+ memcpy(buf, prefix, strlen(prefix));
+
+ return 0;
+}
+
static int __devinit virtblk_probe(struct virtio_device *vdev)
{
struct virtio_blk *vblk;
@@ -442,18 +467,7 @@ static int __devinit virtblk_probe(struct virtio_device
*vdev)
q->queuedata = vblk;
- if (index < 26) {
- sprintf(vblk->disk->disk_name, "vd%c", 'a' + index %
26);
- } else if (index < (26 + 1) * 26) {
- sprintf(vblk->disk->disk_name, "vd%c%c",
- 'a' + index / 26 - 1, 'a' + index % 26);
- } else {
- const unsigned int m1 = (index / 26 - 1) / 26 - 1;
- const unsigned int m2 = (index / 26 - 1) % 26;
- const unsigned int m3 = index % 26;
- sprintf(vblk->disk->disk_name, "vd%c%c%c",
- 'a' + m1, 'a' + m2, 'a' + m3);
- }
+ virtblk_name_format("vd", index, vblk->disk->disk_name,
DISK_NAME_LEN);
vblk->disk->major = major;
vblk->disk->first_minor = index_to_minor(index);
--
1.7.1
Asias He
2012-Apr-10 13:08 UTC
[PATCH] virtio_blk: Add help function to format mass of disks
On 04/10/2012 03:28 PM, Ren Mingxin wrote:> The current virtio block's naming algorithm just supports 18278 > (26^3 + 26^2 + 26) disks. If there are mass of virtio blocks, > there will be disks with the same name. > > Based on commit 3e1a7ff8a0a7b948f2684930166954f9e8e776fe, I add > function "virtblk_name_format()" for virtio block to support mass > of disks naming. > > Signed-off-by: Ren Mingxin<renmx at cn.fujitsu.com>Make sense to me. Acked-by: Asias He <asias at redhat.com>> --- > drivers/block/virtio_blk.c | 38 ++++++++++++++++++++++++++------------ > 1 files changed, 26 insertions(+), 12 deletions(-) > > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c > index c4a60ba..86516c8 100644 > --- a/drivers/block/virtio_blk.c > +++ b/drivers/block/virtio_blk.c > @@ -374,6 +374,31 @@ static int init_vq(struct virtio_blk *vblk) > return err; > } > > +static int virtblk_name_format(char *prefix, int index, char *buf, int buflen) > +{ > + const int base = 'z' - 'a' + 1; > + char *begin = buf + strlen(prefix); > + char *begin = buf + strlen(prefix); > + char *end = buf + buflen; > + char *p; > + int unit; > + > + p = end - 1; > + *p = '\0'; > + unit = base; > + do { > + if (p == begin) > + return -EINVAL; > + *--p = 'a' + (index % unit); > + index = (index / unit) - 1; > + } while (index>= 0); > + > + memmove(begin, p, end - p); > + memcpy(buf, prefix, strlen(prefix)); > + > + return 0; > +} > + > static int __devinit virtblk_probe(struct virtio_device *vdev) > { > struct virtio_blk *vblk; > @@ -442,18 +467,7 @@ static int __devinit virtblk_probe(struct virtio_device *vdev) > > q->queuedata = vblk; > > - if (index< 26) { > - sprintf(vblk->disk->disk_name, "vd%c", 'a' + index % 26); > - } else if (index< (26 + 1) * 26) { > - sprintf(vblk->disk->disk_name, "vd%c%c", > - 'a' + index / 26 - 1, 'a' + index % 26); > - } else { > - const unsigned int m1 = (index / 26 - 1) / 26 - 1; > - const unsigned int m2 = (index / 26 - 1) % 26; > - const unsigned int m3 = index % 26; > - sprintf(vblk->disk->disk_name, "vd%c%c%c", > - 'a' + m1, 'a' + m2, 'a' + m3); > - } > + virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN); > > vblk->disk->major = major; > vblk->disk->first_minor = index_to_minor(index);-- Asias
Avi Kivity
2012-Apr-10 13:16 UTC
[PATCH] virtio_blk: Add help function to format mass of disks
On 04/10/2012 10:28 AM, Ren Mingxin wrote:> The current virtio block's naming algorithm just supports 18278 > (26^3 + 26^2 + 26) disks. If there are mass of virtio blocks, > there will be disks with the same name. > > Based on commit 3e1a7ff8a0a7b948f2684930166954f9e8e776fe, I add > function "virtblk_name_format()" for virtio block to support mass > of disks naming. > > Signed-off-by: Ren Mingxin <renmx at cn.fujitsu.com> > --- > drivers/block/virtio_blk.c | 38 ++++++++++++++++++++++++++------------ > 1 files changed, 26 insertions(+), 12 deletions(-) > > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c > index c4a60ba..86516c8 100644 > --- a/drivers/block/virtio_blk.c > +++ b/drivers/block/virtio_blk.c > @@ -374,6 +374,31 @@ static int init_vq(struct virtio_blk *vblk) > return err; > } > > +static int virtblk_name_format(char *prefix, int index, char *buf, int buflen) > +{ > + const int base = 'z' - 'a' + 1; > + char *begin = buf + strlen(prefix); > + char *begin = buf + strlen(prefix);Duplicate line.> + char *end = buf + buflen; > + char *p; > + int unit; > + > + p = end - 1; > + *p = '\0'; > + unit = base;Why not use 'base' below? neither unit nor base change.> + do { > + if (p == begin) > + return -EINVAL; > + *--p = 'a' + (index % unit); > + index = (index / unit) - 1; > + } while (index >= 0); > + > + memmove(begin, p, end - p); > + memcpy(buf, prefix, strlen(prefix)); > + > + return 0; > +} > + >-- error compiling committee.c: too many arguments to function
Michael S. Tsirkin
2012-Apr-11 08:43 UTC
[PATCH] virtio_blk: Add help function to format mass of disks
On Tue, Apr 10, 2012 at 03:28:05PM +0800, Ren Mingxin wrote:> The current virtio block's naming algorithm just supports 18278 > (26^3 + 26^2 + 26) disks. If there are mass of virtio blocks, > there will be disks with the same name. > > Based on commit 3e1a7ff8a0a7b948f2684930166954f9e8e776fe, I add > function "virtblk_name_format()" for virtio block to support mass > of disks naming. > > Signed-off-by: Ren Mingxin <renmx at cn.fujitsu.com>Applied, thanks everyone.> --- > drivers/block/virtio_blk.c | 38 ++++++++++++++++++++++++++------------ > 1 files changed, 26 insertions(+), 12 deletions(-) > > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c > index c4a60ba..86516c8 100644 > --- a/drivers/block/virtio_blk.c > +++ b/drivers/block/virtio_blk.c > @@ -374,6 +374,31 @@ static int init_vq(struct virtio_blk *vblk) > return err; > } > > +static int virtblk_name_format(char *prefix, int index, char *buf, int buflen) > +{ > + const int base = 'z' - 'a' + 1; > + char *begin = buf + strlen(prefix); > + char *begin = buf + strlen(prefix); > + char *end = buf + buflen; > + char *p; > + int unit; > + > + p = end - 1; > + *p = '\0'; > + unit = base; > + do { > + if (p == begin) > + return -EINVAL; > + *--p = 'a' + (index % unit); > + index = (index / unit) - 1; > + } while (index >= 0); > + > + memmove(begin, p, end - p); > + memcpy(buf, prefix, strlen(prefix)); > + > + return 0; > +} > + > static int __devinit virtblk_probe(struct virtio_device *vdev) > { > struct virtio_blk *vblk; > @@ -442,18 +467,7 @@ static int __devinit virtblk_probe(struct virtio_device *vdev) > > q->queuedata = vblk; > > - if (index < 26) { > - sprintf(vblk->disk->disk_name, "vd%c", 'a' + index % 26); > - } else if (index < (26 + 1) * 26) { > - sprintf(vblk->disk->disk_name, "vd%c%c", > - 'a' + index / 26 - 1, 'a' + index % 26); > - } else { > - const unsigned int m1 = (index / 26 - 1) / 26 - 1; > - const unsigned int m2 = (index / 26 - 1) % 26; > - const unsigned int m3 = index % 26; > - sprintf(vblk->disk->disk_name, "vd%c%c%c", > - 'a' + m1, 'a' + m2, 'a' + m3); > - } > + virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN); > > vblk->disk->major = major; > vblk->disk->first_minor = index_to_minor(index); > -- > 1.7.1
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