sys-kernel/zfs-dkms : fix kernel 5.5 compat

2 files changed, 35 insertions, 136 deletions

diff --git a/sys-kernel/zfs-dkms/files/2fcab8795c7c493845bfa277d44bc443802000b8.patch b/sys-kernel/zfs-dkms/files/2fcab8795c7c493845bfa277d44bc443802000b8.patch
deleted file mode 100644
index f636e87f..00000000
--- a/sys-kernel/zfs-dkms/files/2fcab8795c7c493845bfa277d44bc443802000b8.patch
+++ /dev/null
@@ -1,136 +0,0 @@
-From 2fcab8795c7c493845bfa277d44bc443802000b8 Mon Sep 17 00:00:00 2001
-From: Brian Behlendorf <behlendorf1@llnl.gov>
-Date: Fri, 28 Feb 2020 08:58:39 -0800
-Subject: [PATCH] Linux 5.5 compat: blkg_tryget()
-
-Commit https://github.com/torvalds/linux/commit/9e8d42a0f accidentally
-converted the static inline function blkg_tryget() to GPL-only for
-kernels built with CONFIG_PREEMPT_RCU=y and CONFIG_BLK_CGROUP=y.
-
-Resolve the build issue by providing our own equivalent functionality
-when needed which uses rcu_read_lock_sched() internally as before.
-
-Reviewed-by: Tony Hutter <hutter2@llnl.gov>
-Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
-Closes #9745
-Closes #10072
----
- config/kernel-blkg-tryget.m4 | 37 ++++++++++++++++++++++++++++++++++++
- config/kernel.m4             |  2 ++
- module/zfs/vdev_disk.c       | 32 ++++++++++++++++++++++++++++++-
- 3 files changed, 70 insertions(+), 1 deletion(-)
- create mode 100644 config/kernel-blkg-tryget.m4
-
-diff --git a/config/kernel-blkg-tryget.m4 b/config/kernel-blkg-tryget.m4
-new file mode 100644
-index 00000000000..fb831ca3b3e
---- /dev/null
-+++ b/config/kernel-blkg-tryget.m4
-@@ -0,0 +1,37 @@
-+dnl #
-+dnl # Linux 5.5 API,
-+dnl #
-+dnl # The Linux 5.5 kernel updated percpu_ref_tryget() which is inlined by
-+dnl # blkg_tryget() to use rcu_read_lock() instead of rcu_read_lock_sched().
-+dnl # As a side effect the function was converted to GPL-only.
-+dnl #
-+AC_DEFUN([ZFS_AC_KERNEL_SRC_BLKG_TRYGET], [
-+	ZFS_LINUX_TEST_SRC([blkg_tryget], [
-+		#include <linux/blk-cgroup.h>
-+		#include <linux/bio.h>
-+		#include <linux/fs.h>
-+	],[
-+		struct blkcg_gq blkg __attribute__ ((unused));
-+		bool rc __attribute__ ((unused));
-+		rc = blkg_tryget(&blkg);
-+	], [], [$ZFS_META_LICENSE])
-+])
-+
-+AC_DEFUN([ZFS_AC_KERNEL_BLKG_TRYGET], [
-+	AC_MSG_CHECKING([whether blkg_tryget() is available])
-+	ZFS_LINUX_TEST_RESULT([blkg_tryget], [
-+		AC_MSG_RESULT(yes)
-+		AC_DEFINE(HAVE_BLKG_TRYGET, 1, [blkg_tryget() is available])
-+
-+		AC_MSG_CHECKING([whether blkg_tryget() is GPL-only])
-+		ZFS_LINUX_TEST_RESULT([blkg_tryget_license], [
-+			AC_MSG_RESULT(no)
-+		],[
-+			AC_MSG_RESULT(yes)
-+			AC_DEFINE(HAVE_BLKG_TRYGET_GPL_ONLY, 1,
-+			    [blkg_tryget() GPL-only])
-+		])
-+	],[
-+		AC_MSG_RESULT(no)
-+	])
-+])
-diff --git a/config/kernel.m4 b/config/kernel.m4
-index dce619729d4..bea6f9b1bbf 100644
---- a/config/kernel.m4
-+++ b/config/kernel.m4
-@@ -70,6 +70,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_SRC], [
- 	ZFS_AC_KERNEL_SRC_BIO_BI_STATUS
- 	ZFS_AC_KERNEL_SRC_BIO_RW_BARRIER
- 	ZFS_AC_KERNEL_SRC_BIO_RW_DISCARD
-+	ZFS_AC_KERNEL_SRC_BLKG_TRYGET
- 	ZFS_AC_KERNEL_SRC_BLK_QUEUE_BDI
- 	ZFS_AC_KERNEL_SRC_BLK_QUEUE_DISCARD
- 	ZFS_AC_KERNEL_SRC_BLK_QUEUE_SECURE_ERASE
-@@ -186,6 +187,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_RESULT], [
- 	ZFS_AC_KERNEL_BIO_BI_STATUS
- 	ZFS_AC_KERNEL_BIO_RW_BARRIER
- 	ZFS_AC_KERNEL_BIO_RW_DISCARD
-+	ZFS_AC_KERNEL_BLKG_TRYGET
- 	ZFS_AC_KERNEL_BLK_QUEUE_BDI
- 	ZFS_AC_KERNEL_BLK_QUEUE_DISCARD
- 	ZFS_AC_KERNEL_BLK_QUEUE_SECURE_ERASE
-diff --git a/module/zfs/vdev_disk.c b/module/zfs/vdev_disk.c
-index 661f0f1b727..8544bb8ffb6 100644
---- a/module/zfs/vdev_disk.c
-+++ b/module/zfs/vdev_disk.c
-@@ -473,6 +473,36 @@ vdev_submit_bio_impl(struct bio *bio)
- 
- #ifdef HAVE_BIO_SET_DEV
- #if defined(CONFIG_BLK_CGROUP) && defined(HAVE_BIO_SET_DEV_GPL_ONLY)
-+/*
-+ * The Linux 5.5 kernel updated percpu_ref_tryget() which is inlined by
-+ * blkg_tryget() to use rcu_read_lock() instead of rcu_read_lock_sched().
-+ * As a side effect the function was converted to GPL-only.  Define our
-+ * own version when needed which uses rcu_read_lock_sched().
-+ */
-+#if defined(HAVE_BLKG_TRYGET_GPL_ONLY)
-+static inline bool
-+vdev_blkg_tryget(struct blkcg_gq *blkg)
-+{
-+	struct percpu_ref *ref = &blkg->refcnt;
-+	unsigned long __percpu *count;
-+	bool rc;
-+
-+	rcu_read_lock_sched();
-+
-+	if (__ref_is_percpu(ref, &count)) {
-+		this_cpu_inc(*count);
-+		rc = true;
-+	} else {
-+		rc = atomic_long_inc_not_zero(&ref->count);
-+	}
-+
-+	rcu_read_unlock_sched();
-+
-+	return (rc);
-+}
-+#elif defined(HAVE_BLKG_TRYGET)
-+#define	vdev_blkg_tryget(bg)	blkg_tryget(bg)
-+#endif
- /*
-  * The Linux 5.0 kernel updated the bio_set_dev() macro so it calls the
-  * GPL-only bio_associate_blkg() symbol thus inadvertently converting
-@@ -487,7 +517,7 @@ vdev_bio_associate_blkg(struct bio *bio)
- 	ASSERT3P(q, !=, NULL);
- 	ASSERT3P(bio->bi_blkg, ==, NULL);
- 
--	if (q->root_blkg && blkg_tryget(q->root_blkg))
-+	if (q->root_blkg && vdev_blkg_tryget(q->root_blkg))
- 		bio->bi_blkg = q->root_blkg;
- }
- #define	bio_associate_blkg vdev_bio_associate_blkg
diff --git a/sys-kernel/zfs-dkms/files/kernel-5.5.patch b/sys-kernel/zfs-dkms/files/kernel-5.5.patch
new file mode 100644
index 00000000..8d2a950f
--- /dev/null
+++ b/sys-kernel/zfs-dkms/files/kernel-5.5.patch
@@ -0,0 +1,35 @@
+diff --git a/module/zfs/vdev_disk.c b/module/zfs/vdev_disk.c
+index 4ffc41cca34..cbe9e18316e 100644
+--- a/module/zfs/vdev_disk.c
++++ b/module/zfs/vdev_disk.c
+@@ -473,6 +473,30 @@
+ 
+ #ifdef HAVE_BIO_SET_DEV
+ #if defined(CONFIG_BLK_CGROUP) && defined(HAVE_BIO_SET_DEV_GPL_ONLY)
++static inline bool vdev_percpu_ref_tryget(struct percpu_ref *ref)
++{
++	unsigned long __percpu *percpu_count;
++	bool ret;
++
++	rcu_read_lock_sched();
++
++	if (__ref_is_percpu(ref, &percpu_count)) {
++		this_cpu_inc(*percpu_count);
++		ret = true;
++	} else {
++		ret = atomic_long_inc_not_zero(&ref->count);
++	}
++
++	rcu_read_unlock_sched();
++
++	return ret;
++}
++#define percpu_ref_tryget vdev_percpu_ref_tryget
++static inline bool vdev_blkg_tryget(struct blkcg_gq *blkg)
++{
++	return blkg && vdev_percpu_ref_tryget(&blkg->refcnt);
++}
++#define blkg_tryget vdev_blkg_tryget
+ /*
+  * The Linux 5.0 kernel updated the bio_set_dev() macro so it calls the
+  * GPL-only bio_associate_blkg() symbol thus inadvertently converting