From e04918dc594669068f5d59d567d08db531167188 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Sun, 2 Mar 2025 15:18:24 +0800 Subject: cred: Fix RCU warnings in override/revert_creds Fix RCU warnings in override_creds and revert_creds by turning the RCU pointer into a normal pointer using rcu_replace_pointer. These warnings were previously private to the cred code, but due to the move into the header file they are now polluting unrelated subsystems. Fixes: 49dffdfde462 ("cred: Add a light version of override/revert_creds()") Signed-off-by: Herbert Xu Link: https://lore.kernel.org/r/Z8QGQGW0IaSklKG7@gondor.apana.org.au Signed-off-by: Christian Brauner --- include/linux/cred.h | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) (limited to 'include/linux') diff --git a/include/linux/cred.h b/include/linux/cred.h index 0c3c4b16b469..5658a3bfe803 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -172,18 +172,12 @@ static inline bool cap_ambient_invariant_ok(const struct cred *cred) static inline const struct cred *override_creds(const struct cred *override_cred) { - const struct cred *old = current->cred; - - rcu_assign_pointer(current->cred, override_cred); - return old; + return rcu_replace_pointer(current->cred, override_cred, 1); } static inline const struct cred *revert_creds(const struct cred *revert_cred) { - const struct cred *override_cred = current->cred; - - rcu_assign_pointer(current->cred, revert_cred); - return override_cred; + return rcu_replace_pointer(current->cred, revert_cred, 1); } /** -- cgit v1.2.3 From 3d252160b818045f3a152b13756f6f37ca34639d Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 4 Mar 2025 13:51:38 +0000 Subject: fs/pipe: Read pipe->{head,tail} atomically outside pipe->mutex pipe_readable(), pipe_writable(), and pipe_poll() can read "pipe->head" and "pipe->tail" outside of "pipe->mutex" critical section. When the head and the tail are read individually in that order, there is a window for interruption between the two reads in which both the head and the tail can be updated by concurrent readers and writers. One of the problematic scenarios observed with hackbench running multiple groups on a large server on a particular pipe inode is as follows: pipe->head = 36 pipe->tail = 36 hackbench-118762 [057] ..... 1029.550548: pipe_write: *wakes up: pipe not full* hackbench-118762 [057] ..... 1029.550548: pipe_write: head: 36 -> 37 [tail: 36] hackbench-118762 [057] ..... 1029.550548: pipe_write: *wake up next reader 118740* hackbench-118762 [057] ..... 1029.550548: pipe_write: *wake up next writer 118768* hackbench-118768 [206] ..... 1029.55055X: pipe_write: *writer wakes up* hackbench-118768 [206] ..... 1029.55055X: pipe_write: head = READ_ONCE(pipe->head) [37] ... CPU 206 interrupted (exact wakeup was not traced but 118768 did read head at 37 in traces) hackbench-118740 [057] ..... 1029.550558: pipe_read: *reader wakes up: pipe is not empty* hackbench-118740 [057] ..... 1029.550558: pipe_read: tail: 36 -> 37 [head = 37] hackbench-118740 [057] ..... 1029.550559: pipe_read: *pipe is empty; wakeup writer 118768* hackbench-118740 [057] ..... 1029.550559: pipe_read: *sleeps* hackbench-118766 [185] ..... 1029.550592: pipe_write: *New writer comes in* hackbench-118766 [185] ..... 1029.550592: pipe_write: head: 37 -> 38 [tail: 37] hackbench-118766 [185] ..... 1029.550592: pipe_write: *wakes up reader 118766* hackbench-118740 [185] ..... 1029.550598: pipe_read: *reader wakes up; pipe not empty* hackbench-118740 [185] ..... 1029.550599: pipe_read: tail: 37 -> 38 [head: 38] hackbench-118740 [185] ..... 1029.550599: pipe_read: *pipe is empty* hackbench-118740 [185] ..... 1029.550599: pipe_read: *reader sleeps; wakeup writer 118768* ... CPU 206 switches back to writer hackbench-118768 [206] ..... 1029.550601: pipe_write: tail = READ_ONCE(pipe->tail) [38] hackbench-118768 [206] ..... 1029.550601: pipe_write: pipe_full()? (u32)(37 - 38) >= 16? Yes hackbench-118768 [206] ..... 1029.550601: pipe_write: *writer goes back to sleep* [ Tasks 118740 and 118768 can then indefinitely wait on each other. ] The unsigned arithmetic in pipe_occupancy() wraps around when "pipe->tail > pipe->head" leading to pipe_full() returning true despite the pipe being empty. The case of genuine wraparound of "pipe->head" is handled since pipe buffer has data allowing readers to make progress until the pipe->tail wraps too after which the reader will wakeup a sleeping writer, however, mistaking the pipe to be full when it is in fact empty can lead to readers and writers waiting on each other indefinitely. This issue became more problematic and surfaced as a hang in hackbench after the optimization in commit aaec5a95d596 ("pipe_read: don't wake up the writer if the pipe is still full") significantly reduced the number of spurious wakeups of writers that had previously helped mask the issue. To avoid missing any updates between the reads of "pipe->head" and "pipe->write", unionize the two with a single unsigned long "pipe->head_tail" member that can be loaded atomically. Using "pipe->head_tail" to read the head and the tail ensures the lockless checks do not miss any updates to the head or the tail and since those two are only updated under "pipe->mutex", it ensures that the head is always ahead of, or equal to the tail resulting in correct calculations. [ prateek: commit log, testing on x86 platforms. ] Reported-and-debugged-by: Swapnil Sapkal Closes: https://lore.kernel.org/lkml/e813814e-7094-4673-bc69-731af065a0eb@amd.com/ Reported-by: Alexey Gladkov Closes: https://lore.kernel.org/all/Z8Wn0nTvevLRG_4m@example.org/ Fixes: 8cefc107ca54 ("pipe: Use head and tail pointers for the ring, not cursor and length") Tested-by: Swapnil Sapkal Reviewed-by: Oleg Nesterov Tested-by: Alexey Gladkov Signed-off-by: K Prateek Nayak Signed-off-by: Linus Torvalds --- fs/pipe.c | 19 ++++++++----------- include/linux/pipe_fs_i.h | 39 +++++++++++++++++++++++++++++++++++++-- 2 files changed, 45 insertions(+), 13 deletions(-) (limited to 'include/linux') diff --git a/fs/pipe.c b/fs/pipe.c index ce1af7592780..e8e6698f3698 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -210,11 +210,10 @@ static const struct pipe_buf_operations anon_pipe_buf_ops = { /* Done while waiting without holding the pipe lock - thus the READ_ONCE() */ static inline bool pipe_readable(const struct pipe_inode_info *pipe) { - unsigned int head = READ_ONCE(pipe->head); - unsigned int tail = READ_ONCE(pipe->tail); + union pipe_index idx = { .head_tail = READ_ONCE(pipe->head_tail) }; unsigned int writers = READ_ONCE(pipe->writers); - return !pipe_empty(head, tail) || !writers; + return !pipe_empty(idx.head, idx.tail) || !writers; } static inline unsigned int pipe_update_tail(struct pipe_inode_info *pipe, @@ -417,11 +416,10 @@ static inline int is_packetized(struct file *file) /* Done while waiting without holding the pipe lock - thus the READ_ONCE() */ static inline bool pipe_writable(const struct pipe_inode_info *pipe) { - unsigned int head = READ_ONCE(pipe->head); - unsigned int tail = READ_ONCE(pipe->tail); + union pipe_index idx = { .head_tail = READ_ONCE(pipe->head_tail) }; unsigned int max_usage = READ_ONCE(pipe->max_usage); - return !pipe_full(head, tail, max_usage) || + return !pipe_full(idx.head, idx.tail, max_usage) || !READ_ONCE(pipe->readers); } @@ -659,7 +657,7 @@ pipe_poll(struct file *filp, poll_table *wait) { __poll_t mask; struct pipe_inode_info *pipe = filp->private_data; - unsigned int head, tail; + union pipe_index idx; /* Epoll has some historical nasty semantics, this enables them */ WRITE_ONCE(pipe->poll_usage, true); @@ -680,19 +678,18 @@ pipe_poll(struct file *filp, poll_table *wait) * if something changes and you got it wrong, the poll * table entry will wake you up and fix it. */ - head = READ_ONCE(pipe->head); - tail = READ_ONCE(pipe->tail); + idx.head_tail = READ_ONCE(pipe->head_tail); mask = 0; if (filp->f_mode & FMODE_READ) { - if (!pipe_empty(head, tail)) + if (!pipe_empty(idx.head, idx.tail)) mask |= EPOLLIN | EPOLLRDNORM; if (!pipe->writers && filp->f_pipe != pipe->w_counter) mask |= EPOLLHUP; } if (filp->f_mode & FMODE_WRITE) { - if (!pipe_full(head, tail, pipe->max_usage)) + if (!pipe_full(idx.head, idx.tail, pipe->max_usage)) mask |= EPOLLOUT | EPOLLWRNORM; /* * Most Unices do not set EPOLLERR for FIFOs but on Linux they diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 8ff23bf5a819..3cc4f8eab853 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -31,6 +31,33 @@ struct pipe_buffer { unsigned long private; }; +/* + * Really only alpha needs 32-bit fields, but + * might as well do it for 64-bit architectures + * since that's what we've historically done, + * and it makes 'head_tail' always be a simple + * 'unsigned long'. + */ +#ifdef CONFIG_64BIT +typedef unsigned int pipe_index_t; +#else +typedef unsigned short pipe_index_t; +#endif + +/* + * We have to declare this outside 'struct pipe_inode_info', + * but then we can't use 'union pipe_index' for an anonymous + * union, so we end up having to duplicate this declaration + * below. Annoying. + */ +union pipe_index { + unsigned long head_tail; + struct { + pipe_index_t head; + pipe_index_t tail; + }; +}; + /** * struct pipe_inode_info - a linux kernel pipe * @mutex: mutex protecting the whole thing @@ -58,8 +85,16 @@ struct pipe_buffer { struct pipe_inode_info { struct mutex mutex; wait_queue_head_t rd_wait, wr_wait; - unsigned int head; - unsigned int tail; + + /* This has to match the 'union pipe_index' above */ + union { + unsigned long head_tail; + struct { + pipe_index_t head; + pipe_index_t tail; + }; + }; + unsigned int max_usage; unsigned int ring_size; unsigned int nr_accounted; -- cgit v1.2.3 From 778b94d7ac17b5800aa857222911f09cc986b509 Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Fri, 28 Feb 2025 11:01:53 -0600 Subject: ACPI: platform_profile: Add support for hidden choices MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When two drivers don't support all the same profiles the legacy interface only exports the common profiles. This causes problems for cases where one driver uses low-power but another uses quiet because the result is that neither is exported to sysfs. To allow two drivers to disagree, add support for "hidden choices". Hidden choices are platform profiles that a driver supports to be compatible with the platform profile of another driver. Fixes: 688834743d67 ("ACPI: platform_profile: Allow multiple handlers") Reported-by: Antheas Kapenekakis Closes: https://lore.kernel.org/platform-driver-x86/e64b771e-3255-42ad-9257-5b8fc6c24ac9@gmx.de/T/#mc068042dd29df36c16c8af92664860fc4763974b Signed-off-by: Mario Limonciello Tested-by: Antheas Kapenekakis Tested-by: Derek J. Clark Acked-by: Ilpo Järvinen Link: https://patch.msgid.link/20250228170155.2623386-2-superm1@kernel.org Signed-off-by: Rafael J. Wysocki --- drivers/acpi/platform_profile.c | 94 +++++++++++++++++++++++++++++++--------- include/linux/platform_profile.h | 3 ++ 2 files changed, 76 insertions(+), 21 deletions(-) (limited to 'include/linux') diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c index 2ad53cc6aae5..ef9444482db1 100644 --- a/drivers/acpi/platform_profile.c +++ b/drivers/acpi/platform_profile.c @@ -21,9 +21,15 @@ struct platform_profile_handler { struct device dev; int minor; unsigned long choices[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)]; + unsigned long hidden_choices[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)]; const struct platform_profile_ops *ops; }; +struct aggregate_choices_data { + unsigned long aggregate[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)]; + int count; +}; + static const char * const profile_names[] = { [PLATFORM_PROFILE_LOW_POWER] = "low-power", [PLATFORM_PROFILE_COOL] = "cool", @@ -73,7 +79,7 @@ static int _store_class_profile(struct device *dev, void *data) lockdep_assert_held(&profile_lock); handler = to_pprof_handler(dev); - if (!test_bit(*bit, handler->choices)) + if (!test_bit(*bit, handler->choices) && !test_bit(*bit, handler->hidden_choices)) return -EOPNOTSUPP; return handler->ops->profile_set(dev, *bit); @@ -239,21 +245,44 @@ static const struct class platform_profile_class = { /** * _aggregate_choices - Aggregate the available profile choices * @dev: The device - * @data: The available profile choices + * @arg: struct aggregate_choices_data * * Return: 0 on success, -errno on failure */ -static int _aggregate_choices(struct device *dev, void *data) +static int _aggregate_choices(struct device *dev, void *arg) { + unsigned long tmp[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)]; + struct aggregate_choices_data *data = arg; struct platform_profile_handler *handler; - unsigned long *aggregate = data; lockdep_assert_held(&profile_lock); handler = to_pprof_handler(dev); - if (test_bit(PLATFORM_PROFILE_LAST, aggregate)) - bitmap_copy(aggregate, handler->choices, PLATFORM_PROFILE_LAST); + bitmap_or(tmp, handler->choices, handler->hidden_choices, PLATFORM_PROFILE_LAST); + if (test_bit(PLATFORM_PROFILE_LAST, data->aggregate)) + bitmap_copy(data->aggregate, tmp, PLATFORM_PROFILE_LAST); else - bitmap_and(aggregate, handler->choices, aggregate, PLATFORM_PROFILE_LAST); + bitmap_and(data->aggregate, tmp, data->aggregate, PLATFORM_PROFILE_LAST); + data->count++; + + return 0; +} + +/** + * _remove_hidden_choices - Remove hidden choices from aggregate data + * @dev: The device + * @arg: struct aggregate_choices_data + * + * Return: 0 on success, -errno on failure + */ +static int _remove_hidden_choices(struct device *dev, void *arg) +{ + struct aggregate_choices_data *data = arg; + struct platform_profile_handler *handler; + + lockdep_assert_held(&profile_lock); + handler = to_pprof_handler(dev); + bitmap_andnot(data->aggregate, handler->choices, + handler->hidden_choices, PLATFORM_PROFILE_LAST); return 0; } @@ -270,22 +299,31 @@ static ssize_t platform_profile_choices_show(struct device *dev, struct device_attribute *attr, char *buf) { - unsigned long aggregate[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)]; + struct aggregate_choices_data data = { + .aggregate = { [0 ... BITS_TO_LONGS(PLATFORM_PROFILE_LAST) - 1] = ~0UL }, + .count = 0, + }; int err; - set_bit(PLATFORM_PROFILE_LAST, aggregate); + set_bit(PLATFORM_PROFILE_LAST, data.aggregate); scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) { err = class_for_each_device(&platform_profile_class, NULL, - aggregate, _aggregate_choices); + &data, _aggregate_choices); if (err) return err; + if (data.count == 1) { + err = class_for_each_device(&platform_profile_class, NULL, + &data, _remove_hidden_choices); + if (err) + return err; + } } /* no profile handler registered any more */ - if (bitmap_empty(aggregate, PLATFORM_PROFILE_LAST)) + if (bitmap_empty(data.aggregate, PLATFORM_PROFILE_LAST)) return -EINVAL; - return _commmon_choices_show(aggregate, buf); + return _commmon_choices_show(data.aggregate, buf); } /** @@ -373,7 +411,10 @@ static ssize_t platform_profile_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { - unsigned long choices[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)]; + struct aggregate_choices_data data = { + .aggregate = { [0 ... BITS_TO_LONGS(PLATFORM_PROFILE_LAST) - 1] = ~0UL }, + .count = 0, + }; int ret; int i; @@ -381,13 +422,13 @@ static ssize_t platform_profile_store(struct device *dev, i = sysfs_match_string(profile_names, buf); if (i < 0 || i == PLATFORM_PROFILE_CUSTOM) return -EINVAL; - set_bit(PLATFORM_PROFILE_LAST, choices); + set_bit(PLATFORM_PROFILE_LAST, data.aggregate); scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) { ret = class_for_each_device(&platform_profile_class, NULL, - choices, _aggregate_choices); + &data, _aggregate_choices); if (ret) return ret; - if (!test_bit(i, choices)) + if (!test_bit(i, data.aggregate)) return -EOPNOTSUPP; ret = class_for_each_device(&platform_profile_class, NULL, &i, @@ -453,12 +494,15 @@ EXPORT_SYMBOL_GPL(platform_profile_notify); */ int platform_profile_cycle(void) { + struct aggregate_choices_data data = { + .aggregate = { [0 ... BITS_TO_LONGS(PLATFORM_PROFILE_LAST) - 1] = ~0UL }, + .count = 0, + }; enum platform_profile_option next = PLATFORM_PROFILE_LAST; enum platform_profile_option profile = PLATFORM_PROFILE_LAST; - unsigned long choices[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)]; int err; - set_bit(PLATFORM_PROFILE_LAST, choices); + set_bit(PLATFORM_PROFILE_LAST, data.aggregate); scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) { err = class_for_each_device(&platform_profile_class, NULL, &profile, _aggregate_profiles); @@ -470,14 +514,14 @@ int platform_profile_cycle(void) return -EINVAL; err = class_for_each_device(&platform_profile_class, NULL, - choices, _aggregate_choices); + &data, _aggregate_choices); if (err) return err; /* never iterate into a custom if all drivers supported it */ - clear_bit(PLATFORM_PROFILE_CUSTOM, choices); + clear_bit(PLATFORM_PROFILE_CUSTOM, data.aggregate); - next = find_next_bit_wrap(choices, + next = find_next_bit_wrap(data.aggregate, PLATFORM_PROFILE_LAST, profile + 1); @@ -532,6 +576,14 @@ struct device *platform_profile_register(struct device *dev, const char *name, return ERR_PTR(-EINVAL); } + if (ops->hidden_choices) { + err = ops->hidden_choices(drvdata, pprof->hidden_choices); + if (err) { + dev_err(dev, "platform_profile hidden_choices failed\n"); + return ERR_PTR(err); + } + } + guard(mutex)(&profile_lock); /* create class interface for individual handler */ diff --git a/include/linux/platform_profile.h b/include/linux/platform_profile.h index 8ab5b0e8eb2c..8c9df7dadd5d 100644 --- a/include/linux/platform_profile.h +++ b/include/linux/platform_profile.h @@ -33,6 +33,8 @@ enum platform_profile_option { * @probe: Callback to setup choices available to the new class device. These * choices will only be enforced when setting a new profile, not when * getting the current one. + * @hidden_choices: Callback to setup choices that are not visible to the user + * but can be set by the driver. * @profile_get: Callback that will be called when showing the current platform * profile in sysfs. * @profile_set: Callback that will be called when storing a new platform @@ -40,6 +42,7 @@ enum platform_profile_option { */ struct platform_profile_ops { int (*probe)(void *drvdata, unsigned long *choices); + int (*hidden_choices)(void *drvdata, unsigned long *choices); int (*profile_get)(struct device *dev, enum platform_profile_option *profile); int (*profile_set)(struct device *dev, enum platform_profile_option profile); }; -- cgit v1.2.3 From c27c66afc449b80f3b4b84d123358c0248f2cf63 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 5 Mar 2025 07:08:09 -1000 Subject: fs/pipe: Fix pipe_occupancy() with 16-bit indexes The pipe_occupancy() logic implicitly relied on the natural unsigned modulo arithmetic in C, but that doesn't work for the new 'pipe_index_t' case, since any arithmetic will be done in 'int' (and here we had also made it 'unsigned int' due to the function call boundary). So make the modulo arithmetic explicit by casting the result to the proper type. Cc: Oleg Nesterov Cc: Mateusz Guzik Cc: Manfred Spraul Cc: Christian Brauner Cc: Swapnil Sapkal Cc: Alexey Gladkov Cc: K Prateek Nayak Link: https://lore.kernel.org/all/CAHk-=wjyHsGLx=rxg6PKYBNkPYAejgo7=CbyL3=HGLZLsAaJFQ@mail.gmail.com/ Fixes: 3d252160b818 ("fs/pipe: Read pipe->{head,tail} atomically outside pipe->mutex") Signed-off-by: Linus Torvalds --- include/linux/pipe_fs_i.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 3cc4f8eab853..1f013ed7577e 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -192,7 +192,7 @@ static inline bool pipe_empty(unsigned int head, unsigned int tail) */ static inline unsigned int pipe_occupancy(unsigned int head, unsigned int tail) { - return head - tail; + return (pipe_index_t)(head - tail); } /** -- cgit v1.2.3 From cfced12f5100e50d56bc587299393fd33c1169a9 Mon Sep 17 00:00:00 2001 From: K Prateek Nayak Date: Wed, 5 Mar 2025 11:23:01 +0000 Subject: include/linux/pipe_fs_i: Add htmldoc annotation for "head_tail" member Add htmldoc annotation for the newly introduced "head_tail" member describing it to be a union of the pipe_inode_info's @head and @tail members. Reported-by: Stephen Rothwell Closes: https://lore.kernel.org/lkml/20250305204609.5e64768e@canb.auug.org.au/ Fixes: 3d252160b818 ("fs/pipe: Read pipe->{head,tail} atomically outside pipe->mutex") Signed-off-by: K Prateek Nayak Signed-off-by: Linus Torvalds --- include/linux/pipe_fs_i.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 1f013ed7577e..05ccbc5d0129 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -65,6 +65,7 @@ union pipe_index { * @wr_wait: writer wait point in case of full pipe * @head: The point of buffer production * @tail: The point of buffer consumption + * @head_tail: unsigned long union of @head and @tail * @note_loss: The next read() should insert a data-lost message * @max_usage: The maximum number of slots that may be used in the ring * @ring_size: total number of buffers (should be a power of 2) -- cgit v1.2.3 From 0d2d0f3d93ddd6556f23c917d910becd9925ddeb Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 5 Mar 2025 07:35:40 -1000 Subject: fs/pipe: remove buggy and unused 'helper' function While looking for incorrect users of the pipe head/tail fields (see commit c27c66afc449: "fs/pipe: Fix pipe_occupancy() with 16-bit indexes"), I found a bug in pipe_discard_from() that looked entirely broken. However, the fix is trivial: this buggy function isn't actually called by anything, so let's just remove it ASAP. Signed-off-by: Linus Torvalds --- include/linux/pipe_fs_i.h | 9 --------- 1 file changed, 9 deletions(-) (limited to 'include/linux') diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 05ccbc5d0129..e572e6fc4f81 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -281,15 +281,6 @@ static inline bool pipe_buf_try_steal(struct pipe_inode_info *pipe, return buf->ops->try_steal(pipe, buf); } -static inline void pipe_discard_from(struct pipe_inode_info *pipe, - unsigned int old_head) -{ - unsigned int mask = pipe->ring_size - 1; - - while (pipe->head > old_head) - pipe_buf_release(pipe, &pipe->bufs[--pipe->head & mask]); -} - /* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual memory allocation, whereas PIPE_BUF makes atomicity guarantees. */ #define PIPE_SIZE PAGE_SIZE -- cgit v1.2.3 From 67bab13307c83fb742c2556b06cdc39dbad27f07 Mon Sep 17 00:00:00 2001 From: Ge Yang Date: Wed, 19 Feb 2025 11:46:44 +0800 Subject: mm/hugetlb: wait for hugetlb folios to be freed Since the introduction of commit c77c0a8ac4c52 ("mm/hugetlb: defer freeing of huge pages if in non-task context"), which supports deferring the freeing of hugetlb pages, the allocation of contiguous memory through cma_alloc() may fail probabilistically. In the CMA allocation process, if it is found that the CMA area is occupied by in-use hugetlb folios, these in-use hugetlb folios need to be migrated to another location. When there are no available hugetlb folios in the free hugetlb pool during the migration of in-use hugetlb folios, new folios are allocated from the buddy system. A temporary state is set on the newly allocated folio. Upon completion of the hugetlb folio migration, the temporary state is transferred from the new folios to the old folios. Normally, when the old folios with the temporary state are freed, it is directly released back to the buddy system. However, due to the deferred freeing of hugetlb pages, the PageBuddy() check fails, ultimately leading to the failure of cma_alloc(). Here is a simplified call trace illustrating the process: cma_alloc() ->__alloc_contig_migrate_range() // Migrate in-use hugetlb folios ->unmap_and_move_huge_page() ->folio_putback_hugetlb() // Free old folios ->test_pages_isolated() ->__test_page_isolated_in_pageblock() ->PageBuddy(page) // Check if the page is in buddy To resolve this issue, we have implemented a function named wait_for_freed_hugetlb_folios(). This function ensures that the hugetlb folios are properly released back to the buddy system after their migration is completed. By invoking wait_for_freed_hugetlb_folios() before calling PageBuddy(), we ensure that PageBuddy() will succeed. Link: https://lkml.kernel.org/r/1739936804-18199-1-git-send-email-yangge1116@126.com Fixes: c77c0a8ac4c5 ("mm/hugetlb: defer freeing of huge pages if in non-task context") Signed-off-by: Ge Yang Reviewed-by: Muchun Song Acked-by: David Hildenbrand Cc: Baolin Wang Cc: Barry Song <21cnbao@gmail.com> Cc: Oscar Salvador Cc: Signed-off-by: Andrew Morton --- include/linux/hugetlb.h | 5 +++++ mm/hugetlb.c | 8 ++++++++ mm/page_isolation.c | 10 ++++++++++ 3 files changed, 23 insertions(+) (limited to 'include/linux') diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index ec8c0ccc8f95..dbe76d4f1bfc 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -682,6 +682,7 @@ struct huge_bootmem_page { int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list); int replace_free_hugepage_folios(unsigned long start_pfn, unsigned long end_pfn); +void wait_for_freed_hugetlb_folios(void); struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, unsigned long addr, bool cow_from_owner); struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid, @@ -1066,6 +1067,10 @@ static inline int replace_free_hugepage_folios(unsigned long start_pfn, return 0; } +static inline void wait_for_freed_hugetlb_folios(void) +{ +} + static inline struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, unsigned long addr, bool cow_from_owner) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 163190e89ea1..811b29f77abf 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2943,6 +2943,14 @@ int replace_free_hugepage_folios(unsigned long start_pfn, unsigned long end_pfn) return ret; } +void wait_for_freed_hugetlb_folios(void) +{ + if (llist_empty(&hpage_freelist)) + return; + + flush_work(&free_hpage_work); +} + typedef enum { /* * For either 0/1: we checked the per-vma resv map, and one resv diff --git a/mm/page_isolation.c b/mm/page_isolation.c index c608e9d72865..a051a29e95ad 100644 --- a/mm/page_isolation.c +++ b/mm/page_isolation.c @@ -607,6 +607,16 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn, struct zone *zone; int ret; + /* + * Due to the deferred freeing of hugetlb folios, the hugepage folios may + * not immediately release to the buddy system. This can cause PageBuddy() + * to fail in __test_page_isolated_in_pageblock(). To ensure that the + * hugetlb folios are properly released back to the buddy system, we + * invoke the wait_for_freed_hugetlb_folios() function to wait for the + * release to complete. + */ + wait_for_freed_hugetlb_folios(); + /* * Note: pageblock_nr_pages != MAX_PAGE_ORDER. Then, chunks of free * pages are not aligned to pageblock_nr_pages. -- cgit v1.2.3 From ce6d9c1c2b5cc785016faa11b48b6cd317eb367e Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Mon, 24 Feb 2025 21:20:02 -0500 Subject: NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback Add PF_KCOMPACTD flag and current_is_kcompactd() helper to check for it so nfs_release_folio() can skip calling nfs_wb_folio() from kcompactd. Otherwise NFS can deadlock waiting for kcompactd enduced writeback which recurses back to NFS (which triggers writeback to NFSD via NFS loopback mount on the same host, NFSD blocks waiting for XFS's call to __filemap_get_folio): 6070.550357] INFO: task kcompactd0:58 blocked for more than 4435 seconds. {--- [58] "kcompactd0" [<0>] folio_wait_bit+0xe8/0x200 [<0>] folio_wait_writeback+0x2b/0x80 [<0>] nfs_wb_folio+0x80/0x1b0 [nfs] [<0>] nfs_release_folio+0x68/0x130 [nfs] [<0>] split_huge_page_to_list_to_order+0x362/0x840 [<0>] migrate_pages_batch+0x43d/0xb90 [<0>] migrate_pages_sync+0x9a/0x240 [<0>] migrate_pages+0x93c/0x9f0 [<0>] compact_zone+0x8e2/0x1030 [<0>] compact_node+0xdb/0x120 [<0>] kcompactd+0x121/0x2e0 [<0>] kthread+0xcf/0x100 [<0>] ret_from_fork+0x31/0x40 [<0>] ret_from_fork_asm+0x1a/0x30 ---} [akpm@linux-foundation.org: fix build] Link: https://lkml.kernel.org/r/20250225022002.26141-1-snitzer@kernel.org Fixes: 96780ca55e3c ("NFS: fix up nfs_release_folio() to try to release the page") Signed-off-by: Mike Snitzer Cc: Anna Schumaker Cc: Trond Myklebust Cc: Signed-off-by: Andrew Morton --- fs/nfs/file.c | 3 ++- include/linux/compaction.h | 5 +++++ include/linux/sched.h | 2 +- mm/compaction.c | 3 +++ 4 files changed, 11 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 1bb646752e46..033feeab8c34 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include @@ -457,7 +458,7 @@ static bool nfs_release_folio(struct folio *folio, gfp_t gfp) /* If the private flag is set, then the folio is not freeable */ if (folio_test_private(folio)) { if ((current_gfp_context(gfp) & GFP_KERNEL) != GFP_KERNEL || - current_is_kswapd()) + current_is_kswapd() || current_is_kcompactd()) return false; if (nfs_wb_folio(folio->mapping->host, folio) < 0) return false; diff --git a/include/linux/compaction.h b/include/linux/compaction.h index e94776496049..7bf0c521db63 100644 --- a/include/linux/compaction.h +++ b/include/linux/compaction.h @@ -80,6 +80,11 @@ static inline unsigned long compact_gap(unsigned int order) return 2UL << order; } +static inline int current_is_kcompactd(void) +{ + return current->flags & PF_KCOMPACTD; +} + #ifdef CONFIG_COMPACTION extern unsigned int extfrag_for_order(struct zone *zone, unsigned int order); diff --git a/include/linux/sched.h b/include/linux/sched.h index 9632e3318e0d..9c15365a30c0 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1701,7 +1701,7 @@ extern struct pid *cad_pid; #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */ #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ -#define PF__HOLE__00010000 0x00010000 +#define PF_KCOMPACTD 0x00010000 /* I am kcompactd */ #define PF_KSWAPD 0x00020000 /* I am kswapd */ #define PF_MEMALLOC_NOFS 0x00040000 /* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */ #define PF_MEMALLOC_NOIO 0x00080000 /* All allocations inherit GFP_NOIO. See memalloc_noio_save() */ diff --git a/mm/compaction.c b/mm/compaction.c index 12ed8425fa17..a3203d97123e 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -3181,6 +3181,7 @@ static int kcompactd(void *p) long default_timeout = msecs_to_jiffies(HPAGE_FRAG_CHECK_INTERVAL_MSEC); long timeout = default_timeout; + current->flags |= PF_KCOMPACTD; set_freezable(); pgdat->kcompactd_max_order = 0; @@ -3237,6 +3238,8 @@ static int kcompactd(void *p) pgdat->proactive_compact_trigger = false; } + current->flags &= ~PF_KCOMPACTD; + return 0; } -- cgit v1.2.3 From c29564d8b46f64f5e6e6f1c9c02f7761b7b90963 Mon Sep 17 00:00:00 2001 From: Su Hui Date: Fri, 21 Feb 2025 15:16:25 +0800 Subject: include/linux/log2.h: mark is_power_of_2() with __always_inline When building kernel with randconfig, there is an error: In function `kvm_is_cr4_bit_set',inlined from `kvm_update_cpuid_runtime' at arch/x86/kvm/cpuid.c:310:9: include/linux/compiler_types.h:542:38: error: call to `__compiletime_assert_380' declared with attribute error: BUILD_BUG_ON failed: !is_power_of_2(cr4_bit). '!is_power_of_2(X86_CR4_OSXSAVE)' is False, but gcc treats is_power_of_2() as non-inline function and a compilation error happens. Fix this by marking is_power_of_2() with __always_inline. Link: https://lkml.kernel.org/r/20250221071624.1356899-1-suhui@nfschina.com Signed-off-by: Su Hui Cc: Binbin Wu Cc: Paolo Bonzini Cc: Sean Christopherson Signed-off-by: Andrew Morton --- include/linux/log2.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/log2.h b/include/linux/log2.h index 9f30d087a128..1366cb688a6d 100644 --- a/include/linux/log2.h +++ b/include/linux/log2.h @@ -41,7 +41,7 @@ int __ilog2_u64(u64 n) * *not* considered a power of two. * Return: true if @n is a power of 2, otherwise false. */ -static inline __attribute__((const)) +static __always_inline __attribute__((const)) bool is_power_of_2(unsigned long n) { return (n != 0 && ((n & (n - 1)) == 0)); -- cgit v1.2.3 From 74d42bdb3a4673b1c10d1f457184e4d3c9cb0196 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Thu, 6 Mar 2025 07:30:42 -1000 Subject: fs/pipe: express 'pipe_empty()' in terms of 'pipe_occupancy()' That's what 'pipe_full()' does, so it's more consistent. But more importantly it gets the type limits right when the pipe head and tail are no longer necessarily 'unsigned int'. Signed-off-by: Linus Torvalds --- include/linux/pipe_fs_i.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index e572e6fc4f81..4d0a2267e6ef 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -177,23 +177,23 @@ static inline bool pipe_has_watch_queue(const struct pipe_inode_info *pipe) } /** - * pipe_empty - Return true if the pipe is empty + * pipe_occupancy - Return number of slots used in the pipe * @head: The pipe ring head pointer * @tail: The pipe ring tail pointer */ -static inline bool pipe_empty(unsigned int head, unsigned int tail) +static inline unsigned int pipe_occupancy(unsigned int head, unsigned int tail) { - return head == tail; + return (pipe_index_t)(head - tail); } /** - * pipe_occupancy - Return number of slots used in the pipe + * pipe_empty - Return true if the pipe is empty * @head: The pipe ring head pointer * @tail: The pipe ring tail pointer */ -static inline unsigned int pipe_occupancy(unsigned int head, unsigned int tail) +static inline bool pipe_empty(unsigned int head, unsigned int tail) { - return (pipe_index_t)(head - tail); + return !pipe_occupancy(head, tail); } /** -- cgit v1.2.3 From e7112524e5e885181cc5ae4d258f33b9dbe0b907 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Thu, 6 Mar 2025 08:27:51 -0800 Subject: block: Name the RQF flags enum Commit 5f89154e8e9e3445f9b59 ("block: Use enum to define RQF_x bit indexes") converted the RQF flags to an anonymous enum, which was a beneficial change. This patch goes one step further by naming the enum as "rqf_flags". This naming enables exporting these flags to BPF clients, eliminating the need to duplicate these flags in BPF code. Instead, BPF clients can now access the same kernel-side values through CO:RE (Compile Once, Run Everywhere), as shown in this example: rqf_stats = bpf_core_enum_value(enum rqf_flags, __RQF_STATS) Suggested-by: Yonghong Song Signed-off-by: Breno Leitao Link: https://lore.kernel.org/r/20250306-rqf_flags-v1-1-bbd64918b406@debian.org Signed-off-by: Jens Axboe --- include/linux/blk-mq.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index fa2a76cc2f73..71f4f0cc3dac 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -28,7 +28,7 @@ typedef enum rq_end_io_ret (rq_end_io_fn)(struct request *, blk_status_t); typedef __u32 __bitwise req_flags_t; /* Keep rqf_name[] in sync with the definitions below */ -enum { +enum rqf_flags { /* drive already may have started this one */ __RQF_STARTED, /* request for flush sequence */ -- cgit v1.2.3 From 00a7d39898c8010bfd5ff62af31ca5db34421b38 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Thu, 6 Mar 2025 18:25:35 -1000 Subject: fs/pipe: add simpler helpers for common cases The fix to atomically read the pipe head and tail state when not holding the pipe mutex has caused a number of headaches due to the size change of the involved types. It turns out that we don't have _that_ many places that access these fields directly and were affected, but we have more than we strictly should have, because our low-level helper functions have been designed to have intimate knowledge of how the pipes work. And as a result, that random noise of direct 'pipe->head' and 'pipe->tail' accesses makes it harder to pinpoint any actual potential problem spots remaining. For example, we didn't have a "is the pipe full" helper function, but instead had a "given these pipe buffer indexes and this pipe size, is the pipe full". That's because some low-level pipe code does actually want that much more complicated interface. But most other places literally just want a "is the pipe full" helper, and not having it meant that those places ended up being unnecessarily much too aware of this all. It would have been much better if only the very core pipe code that cared had been the one aware of this all. So let's fix it - better late than never. This just introduces the trivial wrappers for "is this pipe full or empty" and to get how many pipe buffers are used, so that instead of writing if (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) the places that literally just want to know if a pipe is full can just say if (pipe_is_full(pipe)) instead. The existing trivial cases were converted with a 'sed' script. This cuts down on the places that access pipe->head and pipe->tail directly outside of the pipe code (and core splice code) quite a lot. The splice code in particular still revels in doing the direct low-level accesses, and the fuse fuse_dev_splice_write() code also seems a bit unnecessarily eager to go very low-level, but it's at least a bit better than it used to be. Signed-off-by: Linus Torvalds --- drivers/char/virtio_console.c | 4 ++-- fs/fuse/dev.c | 2 +- fs/pipe.c | 6 +++--- fs/splice.c | 20 ++++++++++---------- include/linux/pipe_fs_i.h | 27 +++++++++++++++++++++++++++ mm/filemap.c | 7 +++---- mm/shmem.c | 6 +++--- 7 files changed, 49 insertions(+), 23 deletions(-) (limited to 'include/linux') diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 24442485e73e..18f92dd44d45 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -923,14 +923,14 @@ static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe, pipe_lock(pipe); ret = 0; - if (pipe_empty(pipe->head, pipe->tail)) + if (pipe_is_empty(pipe)) goto error_out; ret = wait_port_writable(port, filp->f_flags & O_NONBLOCK); if (ret < 0) goto error_out; - occupancy = pipe_occupancy(pipe->head, pipe->tail); + occupancy = pipe_buf_usage(pipe); buf = alloc_buf(port->portdev->vdev, 0, occupancy); if (!buf) { diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index 3c9caafca9e2..2c3a4d09e500 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -1457,7 +1457,7 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos, if (ret < 0) goto out; - if (pipe_occupancy(pipe->head, pipe->tail) + cs.nr_segs > pipe->max_usage) { + if (pipe_buf_usage(pipe) + cs.nr_segs > pipe->max_usage) { ret = -EIO; goto out; } diff --git a/fs/pipe.c b/fs/pipe.c index 5c872775a6db..4d0799e4e719 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -394,7 +394,7 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to) wake_next_reader = true; mutex_lock(&pipe->mutex); } - if (pipe_empty(pipe->head, pipe->tail)) + if (pipe_is_empty(pipe)) wake_next_reader = false; mutex_unlock(&pipe->mutex); @@ -577,11 +577,11 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from) kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN); wait_event_interruptible_exclusive(pipe->wr_wait, pipe_writable(pipe)); mutex_lock(&pipe->mutex); - was_empty = pipe_empty(pipe->head, pipe->tail); + was_empty = pipe_is_empty(pipe); wake_next_writer = true; } out: - if (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) + if (pipe_is_full(pipe)) wake_next_writer = false; mutex_unlock(&pipe->mutex); diff --git a/fs/splice.c b/fs/splice.c index 28cfa63aa236..23fa5561b944 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -331,7 +331,7 @@ ssize_t copy_splice_read(struct file *in, loff_t *ppos, int i; /* Work out how much data we can actually add into the pipe */ - used = pipe_occupancy(pipe->head, pipe->tail); + used = pipe_buf_usage(pipe); npages = max_t(ssize_t, pipe->max_usage - used, 0); len = min_t(size_t, len, npages * PAGE_SIZE); npages = DIV_ROUND_UP(len, PAGE_SIZE); @@ -527,7 +527,7 @@ static int splice_from_pipe_next(struct pipe_inode_info *pipe, struct splice_des return -ERESTARTSYS; repeat: - while (pipe_empty(pipe->head, pipe->tail)) { + while (pipe_is_empty(pipe)) { if (!pipe->writers) return 0; @@ -820,7 +820,7 @@ ssize_t splice_to_socket(struct pipe_inode_info *pipe, struct file *out, if (signal_pending(current)) break; - while (pipe_empty(pipe->head, pipe->tail)) { + while (pipe_is_empty(pipe)) { ret = 0; if (!pipe->writers) goto out; @@ -968,7 +968,7 @@ static ssize_t do_splice_read(struct file *in, loff_t *ppos, return 0; /* Don't try to read more the pipe has space for. */ - p_space = pipe->max_usage - pipe_occupancy(pipe->head, pipe->tail); + p_space = pipe->max_usage - pipe_buf_usage(pipe); len = min_t(size_t, len, p_space << PAGE_SHIFT); if (unlikely(len > MAX_RW_COUNT)) @@ -1080,7 +1080,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd, more = sd->flags & SPLICE_F_MORE; sd->flags |= SPLICE_F_MORE; - WARN_ON_ONCE(!pipe_empty(pipe->head, pipe->tail)); + WARN_ON_ONCE(!pipe_is_empty(pipe)); while (len) { size_t read_len; @@ -1268,7 +1268,7 @@ static int wait_for_space(struct pipe_inode_info *pipe, unsigned flags) send_sig(SIGPIPE, current, 0); return -EPIPE; } - if (!pipe_full(pipe->head, pipe->tail, pipe->max_usage)) + if (!pipe_is_full(pipe)) return 0; if (flags & SPLICE_F_NONBLOCK) return -EAGAIN; @@ -1652,13 +1652,13 @@ static int ipipe_prep(struct pipe_inode_info *pipe, unsigned int flags) * Check the pipe occupancy without the inode lock first. This function * is speculative anyways, so missing one is ok. */ - if (!pipe_empty(pipe->head, pipe->tail)) + if (!pipe_is_empty(pipe)) return 0; ret = 0; pipe_lock(pipe); - while (pipe_empty(pipe->head, pipe->tail)) { + while (pipe_is_empty(pipe)) { if (signal_pending(current)) { ret = -ERESTARTSYS; break; @@ -1688,13 +1688,13 @@ static int opipe_prep(struct pipe_inode_info *pipe, unsigned int flags) * Check pipe occupancy without the inode lock first. This function * is speculative anyways, so missing one is ok. */ - if (!pipe_full(pipe->head, pipe->tail, pipe->max_usage)) + if (!pipe_is_full(pipe)) return 0; ret = 0; pipe_lock(pipe); - while (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) { + while (pipe_is_full(pipe)) { if (!pipe->readers) { send_sig(SIGPIPE, current, 0); ret = -EPIPE; diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 4d0a2267e6ef..b698758000f8 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -208,6 +208,33 @@ static inline bool pipe_full(unsigned int head, unsigned int tail, return pipe_occupancy(head, tail) >= limit; } +/** + * pipe_is_full - Return true if the pipe is full + * @pipe: the pipe + */ +static inline bool pipe_is_full(const struct pipe_inode_info *pipe) +{ + return pipe_full(pipe->head, pipe->tail, pipe->max_usage); +} + +/** + * pipe_is_empty - Return true if the pipe is empty + * @pipe: the pipe + */ +static inline bool pipe_is_empty(const struct pipe_inode_info *pipe) +{ + return pipe_empty(pipe->head, pipe->tail); +} + +/** + * pipe_buf_usage - Return how many pipe buffers are in use + * @pipe: the pipe + */ +static inline unsigned int pipe_buf_usage(const struct pipe_inode_info *pipe) +{ + return pipe_occupancy(pipe->head, pipe->tail); +} + /** * pipe_buf - Return the pipe buffer for the specified slot in the pipe ring * @pipe: The pipe to access diff --git a/mm/filemap.c b/mm/filemap.c index d4564a79eb35..2974691fdfad 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2897,8 +2897,7 @@ size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, size = min(size, folio_size(folio) - offset); offset %= PAGE_SIZE; - while (spliced < size && - !pipe_full(pipe->head, pipe->tail, pipe->max_usage)) { + while (spliced < size && !pipe_is_full(pipe)) { struct pipe_buffer *buf = pipe_head_buf(pipe); size_t part = min_t(size_t, PAGE_SIZE - offset, size - spliced); @@ -2955,7 +2954,7 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos, iocb.ki_pos = *ppos; /* Work out how much data we can actually add into the pipe */ - used = pipe_occupancy(pipe->head, pipe->tail); + used = pipe_buf_usage(pipe); npages = max_t(ssize_t, pipe->max_usage - used, 0); len = min_t(size_t, len, npages * PAGE_SIZE); @@ -3015,7 +3014,7 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos, total_spliced += n; *ppos += n; in->f_ra.prev_pos = *ppos; - if (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) + if (pipe_is_full(pipe)) goto out; } diff --git a/mm/shmem.c b/mm/shmem.c index 4ea6109a8043..20032a333d80 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -3487,7 +3487,7 @@ static size_t splice_zeropage_into_pipe(struct pipe_inode_info *pipe, size = min_t(size_t, size, PAGE_SIZE - offset); - if (!pipe_full(pipe->head, pipe->tail, pipe->max_usage)) { + if (!pipe_is_full(pipe)) { struct pipe_buffer *buf = pipe_head_buf(pipe); *buf = (struct pipe_buffer) { @@ -3514,7 +3514,7 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos, int error = 0; /* Work out how much data we can actually add into the pipe */ - used = pipe_occupancy(pipe->head, pipe->tail); + used = pipe_buf_usage(pipe); npages = max_t(ssize_t, pipe->max_usage - used, 0); len = min_t(size_t, len, npages * PAGE_SIZE); @@ -3601,7 +3601,7 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos, total_spliced += n; *ppos += n; in->f_ra.prev_pos = *ppos; - if (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) + if (pipe_is_full(pipe)) break; cond_resched(); -- cgit v1.2.3 From 366fef794bd2b7c2e9df933f6828dd9739bfba84 Mon Sep 17 00:00:00 2001 From: Ilpo Järvinen Date: Mon, 10 Mar 2025 14:21:58 +0200 Subject: : Allow the passing of both iomem and non-iomem pointers to no_free_ptr() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Calling no_free_ptr() for an __iomem pointer results in Sparse complaining about the types: warning: incorrect type in argument 1 (different address spaces) expected void const volatile *val got void [noderef] __iomem *__val [ The example is from drivers/platform/x86/intel/pmc/core_ssram.c:283 ] The problem is caused by the signature of __must_check_fn() added in: 85be6d842447 ("cleanup: Make no_free_ptr() __must_check") ... to enforce that the return value is always used. Use __force to allow both iomem and non-iomem pointers to be given for no_free_ptr(). Reported-by: kernel test robot Signed-off-by: Ilpo Järvinen Signed-off-by: Ingo Molnar Reviewed-by: Andy Shevchenko Reviewed-by: Dan Williams Cc: "H. Peter Anvin" Cc: Linus Torvalds Link: https://lore.kernel.org/r/20250310122158.20966-1-ilpo.jarvinen@linux.intel.com Closes: https://lore.kernel.org/oe-kbuild-all/202403050547.qnZtuNlN-lkp@intel.com/ --- include/linux/cleanup.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/cleanup.h b/include/linux/cleanup.h index ec00e3f7af2b..ee2614adb785 100644 --- a/include/linux/cleanup.h +++ b/include/linux/cleanup.h @@ -212,7 +212,7 @@ const volatile void * __must_check_fn(const volatile void *val) { return val; } #define no_free_ptr(p) \ - ((typeof(p)) __must_check_fn(__get_and_null(p, NULL))) + ((typeof(p)) __must_check_fn((__force const volatile void *)__get_and_null(p, NULL))) #define return_ptr(p) return no_free_ptr(p) -- cgit v1.2.3 From 9bce6b5f8987678b9c6c1fe433af6b5fe41feadc Mon Sep 17 00:00:00 2001 From: Shin'ichiro Kawasaki Date: Tue, 11 Mar 2025 19:43:59 +0900 Subject: block: change blk_mq_add_to_batch() third argument type to bool Commit 1f47ed294a2b ("block: cleanup and fix batch completion adding conditions") modified the evaluation criteria for the third argument, 'ioerror', in the blk_mq_add_to_batch() function. Initially, the function had checked if 'ioerror' equals zero. Following the commit, it started checking for negative error values, with the presumption that such values, for instance -EIO, would be passed in. However, blk_mq_add_to_batch() callers do not pass negative error values. Instead, they pass status codes defined in various ways: - NVMe PCI and Apple drivers pass NVMe status code - virtio_blk driver passes the virtblk request header status byte - null_blk driver passes blk_status_t These codes are either zero or positive, therefore the revised check fails to function as intended. Specifically, with the NVMe PCI driver, this modification led to the failure of the blktests test case nvme/039. In this test scenario, errors are artificially injected to the NVMe driver, resulting in positive NVMe status codes passed to blk_mq_add_to_batch(), which unexpectedly processes the failed I/O in a batch. Hence the failure. To correct the ioerror check within blk_mq_add_to_batch(), make all callers to uniformly pass the argument as boolean. Modify the callers to check their specific status codes and pass the boolean value 'is_error'. Also describe the arguments of blK_mq_add_to_batch as kerneldoc. Fixes: 1f47ed294a2b ("block: cleanup and fix batch completion adding conditions") Signed-off-by: Shin'ichiro Kawasaki Link: https://lore.kernel.org/r/20250311104359.1767728-3-shinichiro.kawasaki@wdc.com [axboe: fold in documentation update] Signed-off-by: Jens Axboe --- drivers/block/null_blk/main.c | 4 ++-- drivers/block/virtio_blk.c | 5 +++-- drivers/nvme/host/apple.c | 3 ++- drivers/nvme/host/pci.c | 5 +++-- include/linux/blk-mq.h | 16 ++++++++++++---- 5 files changed, 22 insertions(+), 11 deletions(-) (limited to 'include/linux') diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c index d94ef37480bd..fdc7a0b2af10 100644 --- a/drivers/block/null_blk/main.c +++ b/drivers/block/null_blk/main.c @@ -1549,8 +1549,8 @@ static int null_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob) cmd = blk_mq_rq_to_pdu(req); cmd->error = null_process_cmd(cmd, req_op(req), blk_rq_pos(req), blk_rq_sectors(req)); - if (!blk_mq_add_to_batch(req, iob, (__force int) cmd->error, - blk_mq_end_request_batch)) + if (!blk_mq_add_to_batch(req, iob, cmd->error != BLK_STS_OK, + blk_mq_end_request_batch)) blk_mq_end_request(req, cmd->error); nr++; } diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index a4af39fc7ea2..286cab5e5368 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -1207,11 +1207,12 @@ static int virtblk_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob) while ((vbr = virtqueue_get_buf(vq->vq, &len)) != NULL) { struct request *req = blk_mq_rq_from_pdu(vbr); + u8 status = virtblk_vbr_status(vbr); found++; if (!blk_mq_complete_request_remote(req) && - !blk_mq_add_to_batch(req, iob, virtblk_vbr_status(vbr), - virtblk_complete_batch)) + !blk_mq_add_to_batch(req, iob, status != VIRTIO_BLK_S_OK, + virtblk_complete_batch)) virtblk_request_done(req); } diff --git a/drivers/nvme/host/apple.c b/drivers/nvme/host/apple.c index a060f69558e7..8971aca41e63 100644 --- a/drivers/nvme/host/apple.c +++ b/drivers/nvme/host/apple.c @@ -599,7 +599,8 @@ static inline void apple_nvme_handle_cqe(struct apple_nvme_queue *q, } if (!nvme_try_complete_req(req, cqe->status, cqe->result) && - !blk_mq_add_to_batch(req, iob, nvme_req(req)->status, + !blk_mq_add_to_batch(req, iob, + nvme_req(req)->status != NVME_SC_SUCCESS, apple_nvme_complete_batch)) apple_nvme_complete_rq(req); } diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 640590b21728..75de86e235ad 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1130,8 +1130,9 @@ static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, trace_nvme_sq(req, cqe->sq_head, nvmeq->sq_tail); if (!nvme_try_complete_req(req, cqe->status, cqe->result) && - !blk_mq_add_to_batch(req, iob, nvme_req(req)->status, - nvme_pci_complete_batch)) + !blk_mq_add_to_batch(req, iob, + nvme_req(req)->status != NVME_SC_SUCCESS, + nvme_pci_complete_batch)) nvme_pci_complete_rq(req); } diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 71f4f0cc3dac..aba9c24486aa 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -852,12 +852,20 @@ static inline bool blk_mq_is_reserved_rq(struct request *rq) return rq->rq_flags & RQF_RESV; } -/* +/** + * blk_mq_add_to_batch() - add a request to the completion batch + * @req: The request to add to batch + * @iob: The batch to add the request + * @is_error: Specify true if the request failed with an error + * @complete: The completaion handler for the request + * * Batched completions only work when there is no I/O error and no special * ->end_io handler. + * + * Return: true when the request was added to the batch, otherwise false */ static inline bool blk_mq_add_to_batch(struct request *req, - struct io_comp_batch *iob, int ioerror, + struct io_comp_batch *iob, bool is_error, void (*complete)(struct io_comp_batch *)) { /* @@ -865,7 +873,7 @@ static inline bool blk_mq_add_to_batch(struct request *req, * 1) No batch container * 2) Has scheduler data attached * 3) Not a passthrough request and end_io set - * 4) Not a passthrough request and an ioerror + * 4) Not a passthrough request and failed with an error */ if (!iob) return false; @@ -874,7 +882,7 @@ static inline bool blk_mq_add_to_batch(struct request *req, if (!blk_rq_is_passthrough(req)) { if (req->end_io) return false; - if (ioerror < 0) + if (is_error) return false; } -- cgit v1.2.3 From 066e053fe208a3b83ee89dc5a192146add688861 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Wed, 12 Mar 2025 08:38:47 +0100 Subject: fsnotify: add pre-content hooks on mmap() Pre-content hooks in page faults introduces potential deadlock of HSM handler in userspace with filesystem freezing. The requirement with pre-content event is that for every accessed file range an event covering at least this range will be generated at least once before the file data is accesses. In preparation to disabling pre-content event hooks on page faults, add pre-content hooks at mmap() variants for the entire mmaped range, so HSM can fill content when user requests to map a portion of the file. Note that exec() variant also calls vm_mmap_pgoff() internally to map code sections, so pre-content hooks are also generated in this case. Link: https://lore.kernel.org/linux-fsdevel/7ehxrhbvehlrjwvrduoxsao5k3x4aw275patsb3krkwuq573yv@o2hskrfawbnc/ Suggested-by: Josef Bacik Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara Link: https://patch.msgid.link/20250312073852.2123409-2-amir73il@gmail.com --- include/linux/fsnotify.h | 21 +++++++++++++++++++++ mm/util.c | 3 +++ 2 files changed, 24 insertions(+) (limited to 'include/linux') diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h index 6a33288bd6a1..83d3ac97f826 100644 --- a/include/linux/fsnotify.h +++ b/include/linux/fsnotify.h @@ -170,6 +170,21 @@ static inline int fsnotify_file_area_perm(struct file *file, int perm_mask, return fsnotify_path(&file->f_path, FS_ACCESS_PERM); } +/* + * fsnotify_mmap_perm - permission hook before mmap of file range + */ +static inline int fsnotify_mmap_perm(struct file *file, int prot, + const loff_t off, size_t len) +{ + /* + * mmap() generates only pre-content events. + */ + if (!file || likely(!FMODE_FSNOTIFY_HSM(file->f_mode))) + return 0; + + return fsnotify_pre_content(&file->f_path, &off, len); +} + /* * fsnotify_truncate_perm - permission hook before file truncate */ @@ -223,6 +238,12 @@ static inline int fsnotify_file_area_perm(struct file *file, int perm_mask, return 0; } +static inline int fsnotify_mmap_perm(struct file *file, int prot, + const loff_t off, size_t len) +{ + return 0; +} + static inline int fsnotify_truncate_perm(const struct path *path, loff_t length) { return 0; diff --git a/mm/util.c b/mm/util.c index b6b9684a1438..8c965474d329 100644 --- a/mm/util.c +++ b/mm/util.c @@ -23,6 +23,7 @@ #include #include #include +#include #include @@ -569,6 +570,8 @@ unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr, LIST_HEAD(uf); ret = security_mmap_file(file, prot, flag); + if (!ret) + ret = fsnotify_mmap_perm(file, prot, pgoff >> PAGE_SHIFT, len); if (!ret) { if (mmap_write_lock_killable(mm)) return -EINTR; -- cgit v1.2.3 From 955fbe0ef19df4197595a98d0906c94025c4beef Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Wed, 12 Mar 2025 08:38:50 +0100 Subject: Revert "fsnotify: generate pre-content permission event on page fault" This reverts commit 8392bc2ff8c8bf7c4c5e6dfa71ccd893a3c046f6. In the use case of buffered write whose input buffer is mmapped file on a filesystem with a pre-content mark, the prefaulting of the buffer can happen under the filesystem freeze protection (obtained in vfs_write()) which breaks assumptions of pre-content hook and introduces potential deadlock of HSM handler in userspace with filesystem freezing. Now that we have pre-content hooks at file mmap() time, disable the pre-content event hooks on page fault to avoid the potential deadlock. Reported-by: syzbot+7229071b47908b19d5b7@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-fsdevel/7ehxrhbvehlrjwvrduoxsao5k3x4aw275patsb3krkwuq573yv@o2hskrfawbnc/ Fixes: 8392bc2ff8c8 ("fsnotify: generate pre-content permission event on page fault") Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara Link: https://patch.msgid.link/20250312073852.2123409-5-amir73il@gmail.com --- include/linux/mm.h | 1 - mm/filemap.c | 74 ------------------------------------------------------ mm/nommu.c | 7 ------ 3 files changed, 82 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mm.h b/include/linux/mm.h index 7b1068ddcbb7..8483e09aeb2c 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3420,7 +3420,6 @@ extern vm_fault_t filemap_fault(struct vm_fault *vmf); extern vm_fault_t filemap_map_pages(struct vm_fault *vmf, pgoff_t start_pgoff, pgoff_t end_pgoff); extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf); -extern vm_fault_t filemap_fsnotify_fault(struct vm_fault *vmf); extern unsigned long stack_guard_gap; /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */ diff --git a/mm/filemap.c b/mm/filemap.c index 2974691fdfad..ff5fcdd96136 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -47,7 +47,6 @@ #include #include #include -#include #include #include #include "internal.h" @@ -3336,48 +3335,6 @@ static vm_fault_t filemap_fault_recheck_pte_none(struct vm_fault *vmf) return ret; } -/** - * filemap_fsnotify_fault - maybe emit a pre-content event. - * @vmf: struct vm_fault containing details of the fault. - * - * If we have a pre-content watch on this file we will emit an event for this - * range. If we return anything the fault caller should return immediately, we - * will return VM_FAULT_RETRY if we had to emit an event, which will trigger the - * fault again and then the fault handler will run the second time through. - * - * Return: a bitwise-OR of %VM_FAULT_ codes, 0 if nothing happened. - */ -vm_fault_t filemap_fsnotify_fault(struct vm_fault *vmf) -{ - struct file *fpin = NULL; - int mask = (vmf->flags & FAULT_FLAG_WRITE) ? MAY_WRITE : MAY_ACCESS; - loff_t pos = vmf->pgoff >> PAGE_SHIFT; - size_t count = PAGE_SIZE; - int err; - - /* - * We already did this and now we're retrying with everything locked, - * don't emit the event and continue. - */ - if (vmf->flags & FAULT_FLAG_TRIED) - return 0; - - /* No watches, we're done. */ - if (likely(!FMODE_FSNOTIFY_HSM(vmf->vma->vm_file->f_mode))) - return 0; - - fpin = maybe_unlock_mmap_for_io(vmf, fpin); - if (!fpin) - return VM_FAULT_SIGBUS; - - err = fsnotify_file_area_perm(fpin, mask, &pos, count); - fput(fpin); - if (err) - return VM_FAULT_SIGBUS; - return VM_FAULT_RETRY; -} -EXPORT_SYMBOL_GPL(filemap_fsnotify_fault); - /** * filemap_fault - read in file data for page fault handling * @vmf: struct vm_fault containing details of the fault @@ -3481,37 +3438,6 @@ retry_find: * or because readahead was otherwise unable to retrieve it. */ if (unlikely(!folio_test_uptodate(folio))) { - /* - * If this is a precontent file we have can now emit an event to - * try and populate the folio. - */ - if (!(vmf->flags & FAULT_FLAG_TRIED) && - unlikely(FMODE_FSNOTIFY_HSM(file->f_mode))) { - loff_t pos = folio_pos(folio); - size_t count = folio_size(folio); - - /* We're NOWAIT, we have to retry. */ - if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT) { - folio_unlock(folio); - goto out_retry; - } - - if (mapping_locked) - filemap_invalidate_unlock_shared(mapping); - mapping_locked = false; - - folio_unlock(folio); - fpin = maybe_unlock_mmap_for_io(vmf, fpin); - if (!fpin) - goto out_retry; - - error = fsnotify_file_area_perm(fpin, MAY_ACCESS, &pos, - count); - if (error) - ret = VM_FAULT_SIGBUS; - goto out_retry; - } - /* * If the invalidate lock is not held, the folio was in cache * and uptodate and now it is not. Strange but possible since we diff --git a/mm/nommu.c b/mm/nommu.c index baa79abdaf03..9cb6e99215e2 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1613,13 +1613,6 @@ int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, } EXPORT_SYMBOL(remap_vmalloc_range); -vm_fault_t filemap_fsnotify_fault(struct vm_fault *vmf) -{ - BUG(); - return 0; -} -EXPORT_SYMBOL_GPL(filemap_fsnotify_fault); - vm_fault_t filemap_fault(struct vm_fault *vmf) { BUG(); -- cgit v1.2.3 From fd9582998b9a82ef53a34756de8a1fb86abac972 Mon Sep 17 00:00:00 2001 From: Ernest Van Hoecke Date: Wed, 19 Mar 2025 15:20:55 +0100 Subject: of: Add of_property_read_u16_index There is an of_property_read_u32_index and of_property_read_u64_index. This patch adds a similar helper for u16. Signed-off-by: Ernest Van Hoecke Signed-off-by: Francesco Dolcini Reviewed-by: Rob Herring (Arm) Reviewed-by: Charles Keepax Link: https://patch.msgid.link/20250319142059.46692-2-francesco@dolcini.it Signed-off-by: Mark Brown --- drivers/of/property.c | 33 +++++++++++++++++++++++++++++++++ include/linux/of.h | 9 +++++++++ 2 files changed, 42 insertions(+) (limited to 'include/linux') diff --git a/drivers/of/property.c b/drivers/of/property.c index 208d922cc24c..c1feb631e383 100644 --- a/drivers/of/property.c +++ b/drivers/of/property.c @@ -147,6 +147,39 @@ static void *of_find_property_value_of_size(const struct device_node *np, return prop->value; } +/** + * of_property_read_u16_index - Find and read a u16 from a multi-value property. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @index: index of the u16 in the list of values + * @out_value: pointer to return value, modified only if no error. + * + * Search for a property in a device node and read nth 16-bit value from + * it. + * + * Return: 0 on success, -EINVAL if the property does not exist, + * -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data isn't large enough. + * + * The out_value is modified only if a valid u16 value can be decoded. + */ +int of_property_read_u16_index(const struct device_node *np, + const char *propname, + u32 index, u16 *out_value) +{ + const u16 *val = of_find_property_value_of_size(np, propname, + ((index + 1) * sizeof(*out_value)), + 0, NULL); + + if (IS_ERR(val)) + return PTR_ERR(val); + + *out_value = be16_to_cpup(((__be16 *)val) + index); + return 0; +} +EXPORT_SYMBOL_GPL(of_property_read_u16_index); + /** * of_property_read_u32_index - Find and read a u32 from a multi-value property. * diff --git a/include/linux/of.h b/include/linux/of.h index eaf0e2a2b75c..5e52d90f6408 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -314,6 +314,9 @@ extern struct property *of_find_property(const struct device_node *np, extern bool of_property_read_bool(const struct device_node *np, const char *propname); extern int of_property_count_elems_of_size(const struct device_node *np, const char *propname, int elem_size); +extern int of_property_read_u16_index(const struct device_node *np, + const char *propname, + u32 index, u16 *out_value); extern int of_property_read_u32_index(const struct device_node *np, const char *propname, u32 index, u32 *out_value); @@ -627,6 +630,12 @@ static inline int of_property_count_elems_of_size(const struct device_node *np, return -ENOSYS; } +static inline int of_property_read_u16_index(const struct device_node *np, + const char *propname, u32 index, u16 *out_value) +{ + return -ENOSYS; +} + static inline int of_property_read_u32_index(const struct device_node *np, const char *propname, u32 index, u32 *out_value) { -- cgit v1.2.3