+++ /dev/null
-From 041205afee7e151a0ac10c9b5314186cf65417dc Mon Sep 17 00:00:00 2001
-From: Brian Behlendorf <behlendorf1@llnl.gov>
-Date: Fri, 12 Jul 2019 13:27:24 -0700
-Subject: [PATCH] Linux 5.3 compat: rw_semaphore owner
-
-Commit https://github.com/torvalds/linux/commit/94a9717b updated the
-rwsem's owner field to contain additional flags describing the rwsem's
-state. Rather then update the wrappers to mask out these bits, the
-code no longer relies on the owner stored by the kernel. This does
-increase the size of a krwlock_t but it makes the implementation
-less sensitive to future kernel changes.
-
-Reviewed-by: Tony Hutter <hutter2@llnl.gov>
-Reviewed-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
-Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
-Closes #9029
----
- include/spl/sys/rwlock.h | 68 +++-------------------------------------
- module/spl/spl-rwlock.c | 3 --
- 2 files changed, 5 insertions(+), 66 deletions(-)
-
-diff --git a/include/spl/sys/rwlock.h b/include/spl/sys/rwlock.h
-index 408defac20d..5e052b532a4 100644
---- a/include/spl/sys/rwlock.h
-+++ b/include/spl/sys/rwlock.h
-@@ -78,15 +78,9 @@ typedef enum {
- RW_READER = 2
- } krw_t;
-
--/*
-- * If CONFIG_RWSEM_SPIN_ON_OWNER is defined, rw_semaphore will have an owner
-- * field, so we don't need our own.
-- */
- typedef struct {
- struct rw_semaphore rw_rwlock;
--#ifndef CONFIG_RWSEM_SPIN_ON_OWNER
- kthread_t *rw_owner;
--#endif
- #ifdef CONFIG_LOCKDEP
- krw_type_t rw_type;
- #endif /* CONFIG_LOCKDEP */
-@@ -97,31 +91,19 @@ typedef struct {
- static inline void
- spl_rw_set_owner(krwlock_t *rwp)
- {
--/*
-- * If CONFIG_RWSEM_SPIN_ON_OWNER is defined, down_write, up_write,
-- * downgrade_write and __init_rwsem will set/clear owner for us.
-- */
--#ifndef CONFIG_RWSEM_SPIN_ON_OWNER
- rwp->rw_owner = current;
--#endif
- }
-
- static inline void
- spl_rw_clear_owner(krwlock_t *rwp)
- {
--#ifndef CONFIG_RWSEM_SPIN_ON_OWNER
- rwp->rw_owner = NULL;
--#endif
- }
-
- static inline kthread_t *
- rw_owner(krwlock_t *rwp)
- {
--#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
-- return (SEM(rwp)->owner);
--#else
- return (rwp->rw_owner);
--#endif
- }
-
- #ifdef CONFIG_LOCKDEP
-@@ -148,62 +130,22 @@ spl_rw_lockdep_on_maybe(krwlock_t *rwp) \
- #define spl_rw_lockdep_on_maybe(rwp)
- #endif /* CONFIG_LOCKDEP */
-
--
- static inline int
--RW_WRITE_HELD(krwlock_t *rwp)
-+RW_LOCK_HELD(krwlock_t *rwp)
- {
-- return (rw_owner(rwp) == current);
-+ return (spl_rwsem_is_locked(SEM(rwp)));
- }
-
- static inline int
--RW_LOCK_HELD(krwlock_t *rwp)
-+RW_WRITE_HELD(krwlock_t *rwp)
- {
-- return (spl_rwsem_is_locked(SEM(rwp)));
-+ return (rw_owner(rwp) == current);
- }
-
- static inline int
- RW_READ_HELD(krwlock_t *rwp)
- {
-- if (!RW_LOCK_HELD(rwp))
-- return (0);
--
-- /*
-- * rw_semaphore cheat sheet:
-- *
-- * < 3.16:
-- * There's no rw_semaphore.owner, so use rwp.owner instead.
-- * If rwp.owner == NULL then it's a reader
-- *
-- * 3.16 - 4.7:
-- * rw_semaphore.owner added (https://lwn.net/Articles/596656/)
-- * and CONFIG_RWSEM_SPIN_ON_OWNER introduced.
-- * If rw_semaphore.owner == NULL then it's a reader
-- *
-- * 4.8 - 4.16.16:
-- * RWSEM_READER_OWNED added as an internal #define.
-- * (https://lore.kernel.org/patchwork/patch/678590/)
-- * If rw_semaphore.owner == 1 then it's a reader
-- *
-- * 4.16.17 - 4.19:
-- * RWSEM_OWNER_UNKNOWN introduced as ((struct task_struct *)-1L)
-- * (https://do-db2.lkml.org/lkml/2018/5/15/985)
-- * If rw_semaphore.owner == 1 then it's a reader.
-- *
-- * 4.20+:
-- * RWSEM_OWNER_UNKNOWN changed to ((struct task_struct *)-2L)
-- * (https://lkml.org/lkml/2018/9/6/986)
-- * If rw_semaphore.owner & 1 then it's a reader, and also the reader's
-- * task_struct may be embedded in rw_semaphore->owner.
-- */
--#if defined(CONFIG_RWSEM_SPIN_ON_OWNER) && defined(RWSEM_OWNER_UNKNOWN)
-- if (RWSEM_OWNER_UNKNOWN == (struct task_struct *)-2L) {
-- /* 4.20+ kernels with CONFIG_RWSEM_SPIN_ON_OWNER */
-- return ((unsigned long) SEM(rwp)->owner & 1);
-- }
--#endif
--
-- /* < 4.20 kernel or !CONFIG_RWSEM_SPIN_ON_OWNER */
-- return (rw_owner(rwp) == NULL || (unsigned long) rw_owner(rwp) == 1);
-+ return (RW_LOCK_HELD(rwp) && rw_owner(rwp) == NULL);
- }
-
- /*
-diff --git a/module/spl/spl-rwlock.c b/module/spl/spl-rwlock.c
-index 86727ed1957..886e16924e6 100644
---- a/module/spl/spl-rwlock.c
-+++ b/module/spl/spl-rwlock.c
-@@ -119,9 +119,6 @@ rwsem_tryupgrade(struct rw_semaphore *rwsem)
- if (__rwsem_tryupgrade(rwsem)) {
- rwsem_release(&rwsem->dep_map, 1, _RET_IP_);
- rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_);
--#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
-- rwsem->owner = current;
--#endif
- return (1);
- }
- return (0);
-From e7a99dab2b065ac2f8736a65d1b226d21754d771 Mon Sep 17 00:00:00 2001
-From: Brian Behlendorf <behlendorf1@llnl.gov>
-Date: Fri, 12 Jul 2019 14:06:36 -0700
-Subject: [PATCH] Linux 5.3 compat: retire rw_tryupgrade()
-
-The Linux kernel's rwsem's have never provided an interface to
-allow a reader to be upgraded to a writer. Historically, this
-functionality has been implemented by a SPL wrapper function.
-However, this approach depends on internal knowledge of the
-rw_semaphore and is therefore rather brittle.
-
-Since the ZFS code must always be able to fallback to rw_exit()
-and rw_enter() when an rw_tryupgrade() fails; this functionality
-isn't critical. Furthermore, the only potentially performance
-sensitive consumer is dmu_zfetch() and no decrease in performance
-was observed with this change applied. See the PR comments for
-additional testing details.
-
-Therefore, it is being retired to make the build more robust and
-to simplify the rwlock implementation.
-
-Reviewed-by: Tony Hutter <hutter2@llnl.gov>
-Reviewed-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
-Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
-Closes #9029
----
- include/spl/sys/rwlock.h | 60 +++--------------------
- module/spl/spl-rwlock.c | 101 ---------------------------------------
- 2 files changed, 7 insertions(+), 154 deletions(-)
-
-diff --git a/include/spl/sys/rwlock.h b/include/spl/sys/rwlock.h
-index 5e052b532a4..89e02fa8f04 100644
---- a/include/spl/sys/rwlock.h
-+++ b/include/spl/sys/rwlock.h
-@@ -29,43 +29,6 @@
- #include <linux/rwsem.h>
- #include <linux/sched.h>
-
--/* Linux kernel compatibility */
--#if defined(CONFIG_PREEMPT_RT_FULL)
--#define SPL_RWSEM_SINGLE_READER_VALUE (1)
--#define SPL_RWSEM_SINGLE_WRITER_VALUE (0)
--#elif defined(CONFIG_RWSEM_GENERIC_SPINLOCK)
--#define SPL_RWSEM_SINGLE_READER_VALUE (1)
--#define SPL_RWSEM_SINGLE_WRITER_VALUE (-1)
--#elif defined(RWSEM_ACTIVE_MASK)
--#define SPL_RWSEM_SINGLE_READER_VALUE (RWSEM_ACTIVE_READ_BIAS)
--#define SPL_RWSEM_SINGLE_WRITER_VALUE (RWSEM_ACTIVE_WRITE_BIAS)
--#endif
--
--/* Linux 3.16 changed activity to count for rwsem-spinlock */
--#if defined(CONFIG_PREEMPT_RT_FULL)
--#define RWSEM_COUNT(sem) sem->read_depth
--#elif defined(HAVE_RWSEM_ACTIVITY)
--#define RWSEM_COUNT(sem) sem->activity
--/* Linux 4.8 changed count to an atomic_long_t for !rwsem-spinlock */
--#elif defined(HAVE_RWSEM_ATOMIC_LONG_COUNT)
--#define RWSEM_COUNT(sem) atomic_long_read(&(sem)->count)
--#else
--#define RWSEM_COUNT(sem) sem->count
--#endif
--
--#if defined(RWSEM_SPINLOCK_IS_RAW)
--#define spl_rwsem_lock_irqsave(lk, fl) raw_spin_lock_irqsave(lk, fl)
--#define spl_rwsem_unlock_irqrestore(lk, fl) \
-- raw_spin_unlock_irqrestore(lk, fl)
--#define spl_rwsem_trylock_irqsave(lk, fl) raw_spin_trylock_irqsave(lk, fl)
--#else
--#define spl_rwsem_lock_irqsave(lk, fl) spin_lock_irqsave(lk, fl)
--#define spl_rwsem_unlock_irqrestore(lk, fl) spin_unlock_irqrestore(lk, fl)
--#define spl_rwsem_trylock_irqsave(lk, fl) spin_trylock_irqsave(lk, fl)
--#endif /* RWSEM_SPINLOCK_IS_RAW */
--
--#define spl_rwsem_is_locked(rwsem) rwsem_is_locked(rwsem)
--
- typedef enum {
- RW_DRIVER = 2,
- RW_DEFAULT = 4,
-@@ -133,7 +96,7 @@ spl_rw_lockdep_on_maybe(krwlock_t *rwp) \
- static inline int
- RW_LOCK_HELD(krwlock_t *rwp)
- {
-- return (spl_rwsem_is_locked(SEM(rwp)));
-+ return (rwsem_is_locked(SEM(rwp)));
- }
-
- static inline int
-@@ -170,6 +133,12 @@ RW_READ_HELD(krwlock_t *rwp)
- */
- #define rw_destroy(rwp) ((void) 0)
-
-+/*
-+ * Upgrading a rwsem from a reader to a writer is not supported by the
-+ * Linux kernel. The lock must be dropped and reacquired as a writer.
-+ */
-+#define rw_tryupgrade(rwp) RW_WRITE_HELD(rwp)
-+
- #define rw_tryenter(rwp, rw) \
- ({ \
- int _rc_ = 0; \
-@@ -228,24 +197,9 @@ RW_READ_HELD(krwlock_t *rwp)
- spl_rw_lockdep_on_maybe(rwp); \
- })
-
--#define rw_tryupgrade(rwp) \
--({ \
-- int _rc_ = 0; \
-- \
-- if (RW_WRITE_HELD(rwp)) { \
-- _rc_ = 1; \
-- } else { \
-- spl_rw_lockdep_off_maybe(rwp); \
-- if ((_rc_ = rwsem_tryupgrade(SEM(rwp)))) \
-- spl_rw_set_owner(rwp); \
-- spl_rw_lockdep_on_maybe(rwp); \
-- } \
-- _rc_; \
--})
- /* END CSTYLED */
-
- int spl_rw_init(void);
- void spl_rw_fini(void);
--int rwsem_tryupgrade(struct rw_semaphore *rwsem);
-
- #endif /* _SPL_RWLOCK_H */
-diff --git a/module/spl/spl-rwlock.c b/module/spl/spl-rwlock.c
-index 886e16924e6..10f7c38db4e 100644
---- a/module/spl/spl-rwlock.c
-+++ b/module/spl/spl-rwlock.c
-@@ -24,106 +24,5 @@
- * Solaris Porting Layer (SPL) Reader/Writer Lock Implementation.
- */
-
--#include <sys/rwlock.h>
--#include <linux/module.h>
--
--#if defined(CONFIG_PREEMPT_RT_FULL)
--
--#include <linux/rtmutex.h>
--#define RT_MUTEX_OWNER_MASKALL 1UL
--
--static int
--__rwsem_tryupgrade(struct rw_semaphore *rwsem)
--{
--#if defined(READER_BIAS) && defined(WRITER_BIAS)
-- /*
-- * After the 4.9.20-rt16 kernel the realtime patch series lifted the
-- * single reader restriction. While this could be accommodated by
-- * adding additional compatibility code assume the rwsem can never
-- * be upgraded. All caller must already cleanly handle this case.
-- */
-- return (0);
--#else
-- ASSERT((struct task_struct *)
-- ((unsigned long)rwsem->lock.owner & ~RT_MUTEX_OWNER_MASKALL) ==
-- current);
--
-- /*
-- * Prior to 4.9.20-rt16 kernel the realtime patch series, rwsem is
-- * implemented as a single mutex held by readers and writers alike.
-- * However, this implementation would prevent a thread from taking
-- * a read lock twice, as the mutex would already be locked on
-- * the second attempt. Therefore the implementation allows a
-- * single thread to take a rwsem as read lock multiple times
-- * tracking that nesting as read_depth counter.
-- */
-- if (rwsem->read_depth <= 1) {
-- /*
-- * In case, the current thread has not taken the lock
-- * more than once as read lock, we can allow an
-- * upgrade to a write lock. rwsem_rt.h implements
-- * write locks as read_depth == 0.
-- */
-- rwsem->read_depth = 0;
-- return (1);
-- }
-- return (0);
--#endif
--}
--#elif defined(CONFIG_RWSEM_GENERIC_SPINLOCK)
--static int
--__rwsem_tryupgrade(struct rw_semaphore *rwsem)
--{
-- int ret = 0;
-- unsigned long flags;
-- spl_rwsem_lock_irqsave(&rwsem->wait_lock, flags);
-- if (RWSEM_COUNT(rwsem) == SPL_RWSEM_SINGLE_READER_VALUE &&
-- list_empty(&rwsem->wait_list)) {
-- ret = 1;
-- RWSEM_COUNT(rwsem) = SPL_RWSEM_SINGLE_WRITER_VALUE;
-- }
-- spl_rwsem_unlock_irqrestore(&rwsem->wait_lock, flags);
-- return (ret);
--}
--#elif defined(RWSEM_ACTIVE_MASK)
--#if defined(HAVE_RWSEM_ATOMIC_LONG_COUNT)
--static int
--__rwsem_tryupgrade(struct rw_semaphore *rwsem)
--{
-- long val;
-- val = atomic_long_cmpxchg(&rwsem->count, SPL_RWSEM_SINGLE_READER_VALUE,
-- SPL_RWSEM_SINGLE_WRITER_VALUE);
-- return (val == SPL_RWSEM_SINGLE_READER_VALUE);
--}
--#else
--static int
--__rwsem_tryupgrade(struct rw_semaphore *rwsem)
--{
-- typeof(rwsem->count) val;
-- val = cmpxchg(&rwsem->count, SPL_RWSEM_SINGLE_READER_VALUE,
-- SPL_RWSEM_SINGLE_WRITER_VALUE);
-- return (val == SPL_RWSEM_SINGLE_READER_VALUE);
--}
--#endif
--#else
--static int
--__rwsem_tryupgrade(struct rw_semaphore *rwsem)
--{
-- return (0);
--}
--#endif
--
--int
--rwsem_tryupgrade(struct rw_semaphore *rwsem)
--{
-- if (__rwsem_tryupgrade(rwsem)) {
-- rwsem_release(&rwsem->dep_map, 1, _RET_IP_);
-- rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_);
-- return (1);
-- }
-- return (0);
--}
--EXPORT_SYMBOL(rwsem_tryupgrade);
--
- int spl_rw_init(void) { return 0; }
- void spl_rw_fini(void) { }
-From a9ebdfdd43204b8f907c5395cd68b2d745544730 Mon Sep 17 00:00:00 2001
-From: Tony Hutter <hutter2@llnl.gov>
-Date: Wed, 21 Aug 2019 09:29:23 -0700
-Subject: [PATCH] Linux 5.3: Fix switch() fall though compiler errors
-
-Fix some switch() fall-though compiler errors:
-
- abd.c:1504:9: error: this statement may fall through
-
-Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
-Signed-off-by: Tony Hutter <hutter2@llnl.gov>
-Closes #9170
----
- module/lua/llex.c | 9 ++++++---
- module/zfs/abd.c | 4 ++++
- module/zfs/vdev_raidz_math_scalar.c | 1 +
- 3 files changed, 11 insertions(+), 3 deletions(-)
-
-diff --git a/module/lua/llex.c b/module/lua/llex.c
-index 8760155d054..50c301f599f 100644
---- a/module/lua/llex.c
-+++ b/module/lua/llex.c
-@@ -431,9 +431,12 @@ static int llex (LexState *ls, SemInfo *seminfo) {
- if (sep >= 0) {
- read_long_string(ls, seminfo, sep);
- return TK_STRING;
-- }
-- else if (sep == -1) return '[';
-- else lexerror(ls, "invalid long string delimiter", TK_STRING);
-+ } else if (sep == -1) {
-+ return '[';
-+ } else {
-+ lexerror(ls, "invalid long string delimiter", TK_STRING);
-+ break;
-+ }
- }
- case '=': {
- next(ls);
-diff --git a/module/zfs/abd.c b/module/zfs/abd.c
-index 9f688d9bc2b..8b2514404a8 100644
---- a/module/zfs/abd.c
-+++ b/module/zfs/abd.c
-@@ -1408,8 +1408,10 @@ abd_raidz_gen_iterate(abd_t **cabds, abd_t *dabd,
- switch (parity) {
- case 3:
- len = MIN(caiters[2].iter_mapsize, len);
-+ /* falls through */
- case 2:
- len = MIN(caiters[1].iter_mapsize, len);
-+ /* falls through */
- case 1:
- len = MIN(caiters[0].iter_mapsize, len);
- }
-@@ -1499,9 +1501,11 @@ abd_raidz_rec_iterate(abd_t **cabds, abd_t **tabds,
- case 3:
- len = MIN(xiters[2].iter_mapsize, len);
- len = MIN(citers[2].iter_mapsize, len);
-+ /* falls through */
- case 2:
- len = MIN(xiters[1].iter_mapsize, len);
- len = MIN(citers[1].iter_mapsize, len);
-+ /* falls through */
- case 1:
- len = MIN(xiters[0].iter_mapsize, len);
- len = MIN(citers[0].iter_mapsize, len);
-diff --git a/module/zfs/vdev_raidz_math_scalar.c b/module/zfs/vdev_raidz_math_scalar.c
-index a693bff63ff..cd742e146ca 100644
---- a/module/zfs/vdev_raidz_math_scalar.c
-+++ b/module/zfs/vdev_raidz_math_scalar.c
-@@ -142,6 +142,7 @@ static const struct {
- a.b[6] = mul_lt[a.b[6]]; \
- a.b[5] = mul_lt[a.b[5]]; \
- a.b[4] = mul_lt[a.b[4]]; \
-+ /* falls through */ \
- case 4: \
- a.b[3] = mul_lt[a.b[3]]; \
- a.b[2] = mul_lt[a.b[2]]; \
-From ff4b68eedc307e6e9b7f3890b809cbb0e9d73856 Mon Sep 17 00:00:00 2001
-From: Dominic Pearson <dsp@technoanimal.net>
-Date: Tue, 20 Aug 2019 00:22:52 +0200
-Subject: [PATCH] Linux 5.3 compat: Makefile subdir-m no longer supported
-
-Uses obj-m instead, due to kernel changes.
-
-See LKML: Masahiro Yamada, Tue, 6 Aug 2019 19:03:23 +0900
-
-Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
-Reviewed-by: Tony Hutter <hutter2@llnl.gov>
-Signed-off-by: Dominic Pearson <dsp@technoanimal.net>
-Closes #9169
----
- .gitignore | 11 +++++++++++
- module/Makefile.in | 24 ++++++++++++------------
- 2 files changed, 23 insertions(+), 12 deletions(-)
-
-diff --git a/.gitignore b/.gitignore
-index 549fa59f382..ae9e22dfa7b 100644
---- a/.gitignore
-+++ b/.gitignore
-@@ -63,3 +63,14 @@ cscope.*
- *.log
- venv
-
-+#
-+# Module leftovers
-+#
-+/module/avl/zavl.mod
-+/module/icp/icp.mod
-+/module/lua/zlua.mod
-+/module/nvpair/znvpair.mod
-+/module/spl/spl.mod
-+/module/unicode/zunicode.mod
-+/module/zcommon/zcommon.mod
-+/module/zfs/zfs.mod
-diff --git a/module/Makefile.in b/module/Makefile.in
-index eca7691aedb..7477dbe5650 100644
---- a/module/Makefile.in
-+++ b/module/Makefile.in
-@@ -1,11 +1,11 @@
--subdir-m += avl
--subdir-m += icp
--subdir-m += lua
--subdir-m += nvpair
--subdir-m += spl
--subdir-m += unicode
--subdir-m += zcommon
--subdir-m += zfs
-+obj-m += avl/
-+obj-m += icp/
-+obj-m += lua/
-+obj-m += nvpair/
-+obj-m += spl/
-+obj-m += unicode/
-+obj-m += zcommon/
-+obj-m += zfs/
-
- INSTALL_MOD_DIR ?= extra
-
-@@ -60,14 +60,15 @@ modules_install:
- modules_uninstall:
- @# Uninstall the kernel modules
- kmoddir=$(DESTDIR)$(INSTALL_MOD_PATH)/lib/modules/@LINUX_VERSION@
-- list='$(subdir-m)'; for subdir in $$list; do \
-- $(RM) -R $$kmoddir/$(INSTALL_MOD_DIR)/$$subdir; \
-+ list='$(obj-m)'; for objdir in $$list; do \
-+ $(RM) -R $$kmoddir/$(INSTALL_MOD_DIR)/$$objdir; \
- done
-
- distdir:
-- list='$(subdir-m)'; for subdir in $$list; do \
-- (cd @top_srcdir@/module && find $$subdir -name '*.c' -o -name '*.h' -o -name '*.S' |\
-- xargs cp --parents -t $$distdir); \
-+ list='$(obj-m)'; for objdir in $$list; do \
-+ (cd @top_srcdir@/module && find $$objdir \
-+ -name '*.c' -o -name '*.h' -o -name '*.S' | \
-+ xargs cp --parents -t @abs_top_builddir@/module/$$distdir); \
- done
-
- distclean maintainer-clean: clean
projects / packages / zfs.git / blobdiff