nfs/blocklayout: refactor block device opening

Deduplicate the helpers to open a device node by passing a name
prefix argument and using the same helper for both kinds of paths.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Christoph Hellwig 2022-06-22 15:58:22 +02:00 committed by Trond Myklebust
parent 7ccafd4b2b
commit f931d8374c

View File

@ -301,18 +301,14 @@ bl_validate_designator(struct pnfs_block_volume *v)
}
}
/*
* Try to open the udev path for the WWN. At least on Debian the udev
* by-id path will always point to the dm-multipath device if one exists.
*/
static struct block_device *
bl_open_udev_path(struct pnfs_block_volume *v)
bl_open_path(struct pnfs_block_volume *v, const char *prefix)
{
struct block_device *bdev;
const char *devname;
devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%*phN",
v->scsi.designator_len, v->scsi.designator);
devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/%s%*phN",
prefix, v->scsi.designator_len, v->scsi.designator);
if (!devname)
return ERR_PTR(-ENOMEM);
@ -326,28 +322,6 @@ bl_open_udev_path(struct pnfs_block_volume *v)
return bdev;
}
/*
* Try to open the RH/Fedora specific dm-mpath udev path for this WWN, as the
* wwn- links will only point to the first discovered SCSI device there.
*/
static struct block_device *
bl_open_dm_mpath_udev_path(struct pnfs_block_volume *v)
{
struct block_device *bdev;
const char *devname;
devname = kasprintf(GFP_KERNEL,
"/dev/disk/by-id/dm-uuid-mpath-%d%*phN",
v->scsi.designator_type,
v->scsi.designator_len, v->scsi.designator);
if (!devname)
return ERR_PTR(-ENOMEM);
bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL);
kfree(devname);
return bdev;
}
static int
bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
@ -360,9 +334,15 @@ bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
if (!bl_validate_designator(v))
return -EINVAL;
bdev = bl_open_dm_mpath_udev_path(v);
/*
* Try to open the RH/Fedora specific dm-mpath udev path first, as the
* wwn- links will only point to the first discovered SCSI device there.
* On other distributions like Debian, the default SCSI by-id path will
* point to the dm-multipath device if one exists.
*/
bdev = bl_open_path(v, "dm-uuid-mpath-0x");
if (IS_ERR(bdev))
bdev = bl_open_udev_path(v);
bdev = bl_open_path(v, "wwn-0x");
if (IS_ERR(bdev))
return PTR_ERR(bdev);
d->bdev = bdev;