| Message ID | 1412205729-20938-1-git-send-email-anand.jain@oracle.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Thu, Oct 02, 2014 at 07:22:09AM +0800, Anand Jain wrote: > (I am unable to reproduce the issue, tried to go back with progs versions > but still the same. So as of now this code remains untested, suggest to > wait till we have a reproducible test case). > > Here is a test case which says it all.. > > mkfs.xfs -f $DEV > mkfs.btrfs -f $DEV > mount $DEV $MNT > mount: /dev/vdiskc: more filesystems detected. This should not happen, > use -t <type> to explicitly specify the filesystem type or > use wipefs(8) to clean up the device. > > mount: you must specify the filesystem type > > with this patch btrfs_prepare_device() also wipes old FS if any, > btrfs_prepare_device() is called after we have verified that > user has provided -f option. > > v2: to satisfy the backward compatibility issue, replace > blkid_do_wipe() with local wipe function. Thank you, works for me, added to 3.17 queue. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Thanks. Anand On 10/10/2014 03:39 PM, David Sterba wrote: > On Thu, Oct 02, 2014 at 07:22:09AM +0800, Anand Jain wrote: >> (I am unable to reproduce the issue, tried to go back with progs versions >> but still the same. So as of now this code remains untested, suggest to >> wait till we have a reproducible test case). >> >> Here is a test case which says it all.. >> >> mkfs.xfs -f $DEV >> mkfs.btrfs -f $DEV >> mount $DEV $MNT >> mount: /dev/vdiskc: more filesystems detected. This should not happen, >> use -t <type> to explicitly specify the filesystem type or >> use wipefs(8) to clean up the device. >> >> mount: you must specify the filesystem type >> >> with this patch btrfs_prepare_device() also wipes old FS if any, >> btrfs_prepare_device() is called after we have verified that >> user has provided -f option. >> >> v2: to satisfy the backward compatibility issue, replace >> blkid_do_wipe() with local wipe function. > > Thank you, works for me, added to 3.17 queue. > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/utils.c b/utils.c index fb78dd6..5f21737 100644 --- a/utils.c +++ b/utils.c @@ -680,6 +680,42 @@ int btrfs_add_to_fsid(struct btrfs_trans_handle *trans, return 0; } +static void btrfs_wipe_existing_sb(int fd) +{ + const char *off = NULL; + size_t len = 0; + loff_t offset; + char buf[BUFSIZ]; + int rc = 0; + blkid_probe pr = NULL; + + pr = blkid_new_probe(); + if (!pr) + return; + + if (blkid_probe_set_device(pr, fd, 0, 0)) + goto out; + + rc = blkid_probe_lookup_value(pr, "SBMAGIC_OFFSET", &off, NULL); + if (!rc) + rc = blkid_probe_lookup_value(pr, "SBMAGIC", NULL, &len); + + if (rc || len == 0 || off == NULL) + goto out; + + offset = strtoll(off, NULL, 10); + if (len > sizeof(buf)) + len = sizeof(buf); + + memset(buf, 0, len); + rc = pwrite(fd, buf, len, offset); + fsync(fd); + +out: + blkid_free_probe(pr); + return; +} + int btrfs_prepare_device(int fd, char *file, int zero_end, u64 *block_count_ret, u64 max_block_count, int *mixed, int discard) { @@ -731,6 +767,8 @@ int btrfs_prepare_device(int fd, char *file, int zero_end, u64 *block_count_ret, return 1; } + btrfs_wipe_existing_sb(fd); + *block_count_ret = block_count; return 0; }
(I am unable to reproduce the issue, tried to go back with progs versions but still the same. So as of now this code remains untested, suggest to wait till we have a reproducible test case). Here is a test case which says it all.. mkfs.xfs -f $DEV mkfs.btrfs -f $DEV mount $DEV $MNT mount: /dev/vdiskc: more filesystems detected. This should not happen, use -t <type> to explicitly specify the filesystem type or use wipefs(8) to clean up the device. mount: you must specify the filesystem type with this patch btrfs_prepare_device() also wipes old FS if any, btrfs_prepare_device() is called after we have verified that user has provided -f option. v2: to satisfy the backward compatibility issue, replace blkid_do_wipe() with local wipe function. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.cz> --- utils.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+)