Move partition scanning from userspace to module.

Currently, zpool online -e (dynamic vdev expansion) doesn't work on
whole disks because we're invoking ioctl(BLKRRPART) from userspace
while ZFS still has a partition open on the disk, which results in
EBUSY.

This patch moves the BLKRRPART invocation from the zpool utility to the
module. Specifically, this is done just before opening the device in
vdev_disk_open() which is called inside vdev_reopen(). This requires
jumping through some hoops to get to the disk device from the partition
device, and to make sure we can still open the partition after the
BLKRRPART call.

Note that this new code path is triggered on dynamic vdev expansion
only; other actions, like creating a new pool, are unchanged and still
call BLKRRPART from userspace.

This change also depends on API changes which are available in 2.6.37
and latter kernels.  The build system has been updated to detect this,
but there is no compatibility mode for older kernels.  This means that
online expansion will NOT be available in older kernels.  However, it
will still be possible to expand the vdev offline.

Signed-off-by: Brian Behlendorf <[email protected]>
Closes #808

8 files changed, 16 insertions, 0 deletions

diff --git a/lib/libspl/include/Makefile.in b/lib/libspl/include/Makefile.in
index 73d2fe64d..668183fd3 100644
--- a/lib/libspl/include/Makefile.in
+++ b/lib/libspl/include/Makefile.in
@@ -64,6 +64,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-blk-rq-pos.m4 \
 	$(top_srcdir)/config/kernel-blk-rq-sectors.m4 \
 	$(top_srcdir)/config/kernel-blkdev-get-by-path.m4 \
+	$(top_srcdir)/config/kernel-blkdev-get.m4 \
 	$(top_srcdir)/config/kernel-check-disk-size-change.m4 \
 	$(top_srcdir)/config/kernel-create-umode-t.m4 \
 	$(top_srcdir)/config/kernel-d-make-root.m4 \
@@ -73,6 +74,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-fmode-t.m4 \
 	$(top_srcdir)/config/kernel-fsync.m4 \
 	$(top_srcdir)/config/kernel-get-disk-ro.m4 \
+	$(top_srcdir)/config/kernel-get-gendisk.m4 \
 	$(top_srcdir)/config/kernel-insert-inode-locked.m4 \
 	$(top_srcdir)/config/kernel-invalidate-bdev-args.m4 \
 	$(top_srcdir)/config/kernel-kobj-name-len.m4 \
diff --git a/lib/libspl/include/ia32/Makefile.in b/lib/libspl/include/ia32/Makefile.in
index 32e350e3a..5aff82a93 100644
--- a/lib/libspl/include/ia32/Makefile.in
+++ b/lib/libspl/include/ia32/Makefile.in
@@ -62,6 +62,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-blk-rq-pos.m4 \
 	$(top_srcdir)/config/kernel-blk-rq-sectors.m4 \
 	$(top_srcdir)/config/kernel-blkdev-get-by-path.m4 \
+	$(top_srcdir)/config/kernel-blkdev-get.m4 \
 	$(top_srcdir)/config/kernel-check-disk-size-change.m4 \
 	$(top_srcdir)/config/kernel-create-umode-t.m4 \
 	$(top_srcdir)/config/kernel-d-make-root.m4 \
@@ -71,6 +72,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-fmode-t.m4 \
 	$(top_srcdir)/config/kernel-fsync.m4 \
 	$(top_srcdir)/config/kernel-get-disk-ro.m4 \
+	$(top_srcdir)/config/kernel-get-gendisk.m4 \
 	$(top_srcdir)/config/kernel-insert-inode-locked.m4 \
 	$(top_srcdir)/config/kernel-invalidate-bdev-args.m4 \
 	$(top_srcdir)/config/kernel-kobj-name-len.m4 \
diff --git a/lib/libspl/include/ia32/sys/Makefile.in b/lib/libspl/include/ia32/sys/Makefile.in
index 8bf72d4f5..2ee47ff69 100644
--- a/lib/libspl/include/ia32/sys/Makefile.in
+++ b/lib/libspl/include/ia32/sys/Makefile.in
@@ -64,6 +64,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-blk-rq-pos.m4 \
 	$(top_srcdir)/config/kernel-blk-rq-sectors.m4 \
 	$(top_srcdir)/config/kernel-blkdev-get-by-path.m4 \
+	$(top_srcdir)/config/kernel-blkdev-get.m4 \
 	$(top_srcdir)/config/kernel-check-disk-size-change.m4 \
 	$(top_srcdir)/config/kernel-create-umode-t.m4 \
 	$(top_srcdir)/config/kernel-d-make-root.m4 \
@@ -73,6 +74,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-fmode-t.m4 \
 	$(top_srcdir)/config/kernel-fsync.m4 \
 	$(top_srcdir)/config/kernel-get-disk-ro.m4 \
+	$(top_srcdir)/config/kernel-get-gendisk.m4 \
 	$(top_srcdir)/config/kernel-insert-inode-locked.m4 \
 	$(top_srcdir)/config/kernel-invalidate-bdev-args.m4 \
 	$(top_srcdir)/config/kernel-kobj-name-len.m4 \
diff --git a/lib/libspl/include/rpc/Makefile.in b/lib/libspl/include/rpc/Makefile.in
index c114a8527..6f8e48387 100644
--- a/lib/libspl/include/rpc/Makefile.in
+++ b/lib/libspl/include/rpc/Makefile.in
@@ -64,6 +64,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-blk-rq-pos.m4 \
 	$(top_srcdir)/config/kernel-blk-rq-sectors.m4 \
 	$(top_srcdir)/config/kernel-blkdev-get-by-path.m4 \
+	$(top_srcdir)/config/kernel-blkdev-get.m4 \
 	$(top_srcdir)/config/kernel-check-disk-size-change.m4 \
 	$(top_srcdir)/config/kernel-create-umode-t.m4 \
 	$(top_srcdir)/config/kernel-d-make-root.m4 \
@@ -73,6 +74,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-fmode-t.m4 \
 	$(top_srcdir)/config/kernel-fsync.m4 \
 	$(top_srcdir)/config/kernel-get-disk-ro.m4 \
+	$(top_srcdir)/config/kernel-get-gendisk.m4 \
 	$(top_srcdir)/config/kernel-insert-inode-locked.m4 \
 	$(top_srcdir)/config/kernel-invalidate-bdev-args.m4 \
 	$(top_srcdir)/config/kernel-kobj-name-len.m4 \
diff --git a/lib/libspl/include/sys/Makefile.in b/lib/libspl/include/sys/Makefile.in
index 71fee1785..09d03e99c 100644
--- a/lib/libspl/include/sys/Makefile.in
+++ b/lib/libspl/include/sys/Makefile.in
@@ -64,6 +64,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-blk-rq-pos.m4 \
 	$(top_srcdir)/config/kernel-blk-rq-sectors.m4 \
 	$(top_srcdir)/config/kernel-blkdev-get-by-path.m4 \
+	$(top_srcdir)/config/kernel-blkdev-get.m4 \
 	$(top_srcdir)/config/kernel-check-disk-size-change.m4 \
 	$(top_srcdir)/config/kernel-create-umode-t.m4 \
 	$(top_srcdir)/config/kernel-d-make-root.m4 \
@@ -73,6 +74,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-fmode-t.m4 \
 	$(top_srcdir)/config/kernel-fsync.m4 \
 	$(top_srcdir)/config/kernel-get-disk-ro.m4 \
+	$(top_srcdir)/config/kernel-get-gendisk.m4 \
 	$(top_srcdir)/config/kernel-insert-inode-locked.m4 \
 	$(top_srcdir)/config/kernel-invalidate-bdev-args.m4 \
 	$(top_srcdir)/config/kernel-kobj-name-len.m4 \
diff --git a/lib/libspl/include/sys/dktp/Makefile.in b/lib/libspl/include/sys/dktp/Makefile.in
index e3eeee4ba..30263687f 100644
--- a/lib/libspl/include/sys/dktp/Makefile.in
+++ b/lib/libspl/include/sys/dktp/Makefile.in
@@ -64,6 +64,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-blk-rq-pos.m4 \
 	$(top_srcdir)/config/kernel-blk-rq-sectors.m4 \
 	$(top_srcdir)/config/kernel-blkdev-get-by-path.m4 \
+	$(top_srcdir)/config/kernel-blkdev-get.m4 \
 	$(top_srcdir)/config/kernel-check-disk-size-change.m4 \
 	$(top_srcdir)/config/kernel-create-umode-t.m4 \
 	$(top_srcdir)/config/kernel-d-make-root.m4 \
@@ -73,6 +74,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-fmode-t.m4 \
 	$(top_srcdir)/config/kernel-fsync.m4 \
 	$(top_srcdir)/config/kernel-get-disk-ro.m4 \
+	$(top_srcdir)/config/kernel-get-gendisk.m4 \
 	$(top_srcdir)/config/kernel-insert-inode-locked.m4 \
 	$(top_srcdir)/config/kernel-invalidate-bdev-args.m4 \
 	$(top_srcdir)/config/kernel-kobj-name-len.m4 \
diff --git a/lib/libspl/include/sys/sysevent/Makefile.in b/lib/libspl/include/sys/sysevent/Makefile.in
index d09a7edfd..7106d85df 100644
--- a/lib/libspl/include/sys/sysevent/Makefile.in
+++ b/lib/libspl/include/sys/sysevent/Makefile.in
@@ -64,6 +64,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-blk-rq-pos.m4 \
 	$(top_srcdir)/config/kernel-blk-rq-sectors.m4 \
 	$(top_srcdir)/config/kernel-blkdev-get-by-path.m4 \
+	$(top_srcdir)/config/kernel-blkdev-get.m4 \
 	$(top_srcdir)/config/kernel-check-disk-size-change.m4 \
 	$(top_srcdir)/config/kernel-create-umode-t.m4 \
 	$(top_srcdir)/config/kernel-d-make-root.m4 \
@@ -73,6 +74,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-fmode-t.m4 \
 	$(top_srcdir)/config/kernel-fsync.m4 \
 	$(top_srcdir)/config/kernel-get-disk-ro.m4 \
+	$(top_srcdir)/config/kernel-get-gendisk.m4 \
 	$(top_srcdir)/config/kernel-insert-inode-locked.m4 \
 	$(top_srcdir)/config/kernel-invalidate-bdev-args.m4 \
 	$(top_srcdir)/config/kernel-kobj-name-len.m4 \
diff --git a/lib/libspl/include/util/Makefile.in b/lib/libspl/include/util/Makefile.in
index 6b0cafe76..49f579a64 100644
--- a/lib/libspl/include/util/Makefile.in
+++ b/lib/libspl/include/util/Makefile.in
@@ -64,6 +64,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-blk-rq-pos.m4 \
 	$(top_srcdir)/config/kernel-blk-rq-sectors.m4 \
 	$(top_srcdir)/config/kernel-blkdev-get-by-path.m4 \
+	$(top_srcdir)/config/kernel-blkdev-get.m4 \
 	$(top_srcdir)/config/kernel-check-disk-size-change.m4 \
 	$(top_srcdir)/config/kernel-create-umode-t.m4 \
 	$(top_srcdir)/config/kernel-d-make-root.m4 \
@@ -73,6 +74,7 @@ am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/kernel-fmode-t.m4 \
 	$(top_srcdir)/config/kernel-fsync.m4 \
 	$(top_srcdir)/config/kernel-get-disk-ro.m4 \
+	$(top_srcdir)/config/kernel-get-gendisk.m4 \
 	$(top_srcdir)/config/kernel-insert-inode-locked.m4 \
 	$(top_srcdir)/config/kernel-invalidate-bdev-args.m4 \
 	$(top_srcdir)/config/kernel-kobj-name-len.m4 \