From d702d41ed41328487bd3b270467721222f8036e4 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 8 Jul 2016 18:41:29 +0900 Subject: [PATCH] nfs/blocklayout: refactor open-by-wwn The current code works with the standard udev/systemd names, but we'll have to add another method in the next patch. Refactor it into a separate helper to make room for the new variant. Signed-off-by: Christoph Hellwig Signed-off-by: Trond Myklebust --- fs/nfs/blocklayout/dev.c | 53 ++++++++++++++++++++-------------------- 1 file changed, 27 insertions(+), 26 deletions(-) diff --git a/fs/nfs/blocklayout/dev.c b/fs/nfs/blocklayout/dev.c index 7fb9c07c078c..ea70883a174a 100644 --- a/fs/nfs/blocklayout/dev.c +++ b/fs/nfs/blocklayout/dev.c @@ -287,44 +287,45 @@ 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) +{ + 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); + if (!devname) + return ERR_PTR(-ENOMEM); + + bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL); + if (IS_ERR(bdev)) { + pr_warn("pNFS: failed to open device %s (%ld)\n", + devname, PTR_ERR(bdev)); + } + + 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) { struct pnfs_block_volume *v = &volumes[idx]; const struct pr_ops *ops; - const char *devname; int error; if (!bl_validate_designator(v)) return -EINVAL; - switch (v->scsi.designator_len) { - case 8: - devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%8phN", - v->scsi.designator); - break; - case 12: - devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%12phN", - v->scsi.designator); - break; - case 16: - devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%16phN", - v->scsi.designator); - break; - default: - return -EINVAL; - } - - d->bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL); - if (IS_ERR(d->bdev)) { - pr_warn("pNFS: failed to open device %s (%ld)\n", - devname, PTR_ERR(d->bdev)); - kfree(devname); + d->bdev = bl_open_udev_path(v); + if (IS_ERR(d->bdev)) return PTR_ERR(d->bdev); - } - - kfree(devname); d->len = i_size_read(d->bdev->bd_inode); d->map = bl_map_simple; -- 2.30.2