1
0

release 6.12.5

This commit is contained in:
2024-12-16 07:12:49 +03:00
parent a78998e6a3
commit efeeb92dda
42 changed files with 570 additions and 433 deletions

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@@ -0,0 +1,55 @@
From e50ffd43b88d64b8063a9fce59f1d03b56f6144c Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:42 -0600
Subject: ntsync: Return the fd from NTSYNC_IOC_CREATE_SEM.
Simplify the user API a bit by returning the fd as return value from the ioctl
instead of through the argument pointer.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 7 ++-----
include/uapi/linux/ntsync.h | 3 +--
2 files changed, 3 insertions(+), 7 deletions(-)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -165,7 +165,6 @@ static int ntsync_obj_get_fd(struct ntsy
static int ntsync_create_sem(struct ntsync_device *dev, void __user *argp)
{
- struct ntsync_sem_args __user *user_args = argp;
struct ntsync_sem_args args;
struct ntsync_obj *sem;
int fd;
@@ -182,12 +181,10 @@ static int ntsync_create_sem(struct ntsy
sem->u.sem.count = args.count;
sem->u.sem.max = args.max;
fd = ntsync_obj_get_fd(sem);
- if (fd < 0) {
+ if (fd < 0)
kfree(sem);
- return fd;
- }
- return put_user(fd, &user_args->sem);
+ return fd;
}
static int ntsync_char_open(struct inode *inode, struct file *file)
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -11,12 +11,11 @@
#include <linux/types.h>
struct ntsync_sem_args {
- __u32 sem;
__u32 count;
__u32 max;
};
-#define NTSYNC_IOC_CREATE_SEM _IOWR('N', 0x80, struct ntsync_sem_args)
+#define NTSYNC_IOC_CREATE_SEM _IOW ('N', 0x80, struct ntsync_sem_args)
#define NTSYNC_IOC_SEM_POST _IOWR('N', 0x81, __u32)

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@@ -0,0 +1,64 @@
From 160e9bf7826da868ae4de261753a03cce2208ff6 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:43 -0600
Subject: ntsync: Rename NTSYNC_IOC_SEM_POST to NTSYNC_IOC_SEM_RELEASE.
Use the more common "release" terminology, which is also the term used by NT,
instead of "post" (which is used by POSIX).
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 10 +++++-----
include/uapi/linux/ntsync.h | 2 +-
2 files changed, 6 insertions(+), 6 deletions(-)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -57,7 +57,7 @@ struct ntsync_device {
* Actually change the semaphore state, returning -EOVERFLOW if it is made
* invalid.
*/
-static int post_sem_state(struct ntsync_obj *sem, __u32 count)
+static int release_sem_state(struct ntsync_obj *sem, __u32 count)
{
__u32 sum;
@@ -71,7 +71,7 @@ static int post_sem_state(struct ntsync_
return 0;
}
-static int ntsync_sem_post(struct ntsync_obj *sem, void __user *argp)
+static int ntsync_sem_release(struct ntsync_obj *sem, void __user *argp)
{
__u32 __user *user_args = argp;
__u32 prev_count;
@@ -87,7 +87,7 @@ static int ntsync_sem_post(struct ntsync
spin_lock(&sem->lock);
prev_count = sem->u.sem.count;
- ret = post_sem_state(sem, args);
+ ret = release_sem_state(sem, args);
spin_unlock(&sem->lock);
@@ -114,8 +114,8 @@ static long ntsync_obj_ioctl(struct file
void __user *argp = (void __user *)parm;
switch (cmd) {
- case NTSYNC_IOC_SEM_POST:
- return ntsync_sem_post(obj, argp);
+ case NTSYNC_IOC_SEM_RELEASE:
+ return ntsync_sem_release(obj, argp);
default:
return -ENOIOCTLCMD;
}
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -17,6 +17,6 @@ struct ntsync_sem_args {
#define NTSYNC_IOC_CREATE_SEM _IOW ('N', 0x80, struct ntsync_sem_args)
-#define NTSYNC_IOC_SEM_POST _IOWR('N', 0x81, __u32)
+#define NTSYNC_IOC_SEM_RELEASE _IOWR('N', 0x81, __u32)
#endif

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@@ -0,0 +1,377 @@
From e855a17ec837cdee9047e6e23e47ed7b4312a265 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:44 -0600
Subject: ntsync: Introduce NTSYNC_IOC_WAIT_ANY.
This corresponds to part of the functionality of the NT syscall
NtWaitForMultipleObjects(). Specifically, it implements the behaviour where
the third argument (wait_any) is TRUE, and it does not handle alertable waits.
Those features have been split out into separate patches to ease review.
This patch therefore implements the wait/wake infrastructure which comprises the
core of ntsync's functionality.
NTSYNC_IOC_WAIT_ANY is a vectored wait function similar to poll(). Unlike
poll(), it "consumes" objects when they are signaled. For semaphores, this means
decreasing one from the internal counter. At most one object can be consumed by
this function.
This wait/wake model is fundamentally different from that used anywhere else in
the kernel, and for that reason ntsync does not use any existing infrastructure,
such as futexes, kernel mutexes or semaphores, or wait_event().
Up to 64 objects can be waited on at once. As soon as one is signaled, the
object with the lowest index is consumed, and that index is returned via the
"index" field.
A timeout is supported. The timeout is passed as a u64 nanosecond value, which
represents absolute time measured against either the MONOTONIC or REALTIME clock
(controlled by the flags argument). If U64_MAX is passed, the ioctl waits
indefinitely.
This ioctl validates that all objects belong to the relevant device. This is not
necessary for any technical reason related to NTSYNC_IOC_WAIT_ANY, but will be
necessary for NTSYNC_IOC_WAIT_ALL introduced in the following patch.
Some padding fields are added for alignment and for fields which will be added
in future patches (split out to ease review).
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 247 +++++++++++++++++++++++++++++++++++-
include/uapi/linux/ntsync.h | 14 ++
2 files changed, 260 insertions(+), 1 deletion(-)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -6,11 +6,16 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/atomic.h>
#include <linux/file.h>
#include <linux/fs.h>
+#include <linux/hrtimer.h>
+#include <linux/ktime.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/overflow.h>
+#include <linux/sched.h>
+#include <linux/sched/signal.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <uapi/linux/ntsync.h>
@@ -30,6 +35,8 @@ enum ntsync_type {
*
* Both rely on struct file for reference counting. Individual
* ntsync_obj objects take a reference to the device when created.
+ * Wait operations take a reference to each object being waited on for
+ * the duration of the wait.
*/
struct ntsync_obj {
@@ -47,12 +54,55 @@ struct ntsync_obj {
__u32 max;
} sem;
} u;
+
+ struct list_head any_waiters;
+};
+
+struct ntsync_q_entry {
+ struct list_head node;
+ struct ntsync_q *q;
+ struct ntsync_obj *obj;
+ __u32 index;
+};
+
+struct ntsync_q {
+ struct task_struct *task;
+
+ /*
+ * Protected via atomic_try_cmpxchg(). Only the thread that wins the
+ * compare-and-swap may actually change object states and wake this
+ * task.
+ */
+ atomic_t signaled;
+
+ __u32 count;
+ struct ntsync_q_entry entries[];
};
struct ntsync_device {
struct file *file;
};
+static void try_wake_any_sem(struct ntsync_obj *sem)
+{
+ struct ntsync_q_entry *entry;
+
+ lockdep_assert_held(&sem->lock);
+
+ list_for_each_entry(entry, &sem->any_waiters, node) {
+ struct ntsync_q *q = entry->q;
+ int signaled = -1;
+
+ if (!sem->u.sem.count)
+ break;
+
+ if (atomic_try_cmpxchg(&q->signaled, &signaled, entry->index)) {
+ sem->u.sem.count--;
+ wake_up_process(q->task);
+ }
+ }
+}
+
/*
* Actually change the semaphore state, returning -EOVERFLOW if it is made
* invalid.
@@ -87,7 +137,9 @@ static int ntsync_sem_release(struct nts
spin_lock(&sem->lock);
prev_count = sem->u.sem.count;
- ret = release_sem_state(sem, args);
+ ret = post_sem_state(sem, args);
+ if (!ret)
+ try_wake_any_sem(sem);
spin_unlock(&sem->lock);
@@ -140,6 +192,7 @@ static struct ntsync_obj *ntsync_alloc_o
obj->dev = dev;
get_file(dev->file);
spin_lock_init(&obj->lock);
+ INIT_LIST_HEAD(&obj->any_waiters);
return obj;
}
@@ -187,6 +240,196 @@ static int ntsync_create_sem(struct ntsy
return fd;
}
+static struct ntsync_obj *get_obj(struct ntsync_device *dev, int fd)
+{
+ struct file *file = fget(fd);
+ struct ntsync_obj *obj;
+
+ if (!file)
+ return NULL;
+
+ if (file->f_op != &ntsync_obj_fops) {
+ fput(file);
+ return NULL;
+ }
+
+ obj = file->private_data;
+ if (obj->dev != dev) {
+ fput(file);
+ return NULL;
+ }
+
+ return obj;
+}
+
+static void put_obj(struct ntsync_obj *obj)
+{
+ fput(obj->file);
+}
+
+static int ntsync_schedule(const struct ntsync_q *q, const struct ntsync_wait_args *args)
+{
+ ktime_t timeout = ns_to_ktime(args->timeout);
+ clockid_t clock = CLOCK_MONOTONIC;
+ ktime_t *timeout_ptr;
+ int ret = 0;
+
+ timeout_ptr = (args->timeout == U64_MAX ? NULL : &timeout);
+
+ if (args->flags & NTSYNC_WAIT_REALTIME)
+ clock = CLOCK_REALTIME;
+
+ do {
+ if (signal_pending(current)) {
+ ret = -ERESTARTSYS;
+ break;
+ }
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (atomic_read(&q->signaled) != -1) {
+ ret = 0;
+ break;
+ }
+ ret = schedule_hrtimeout_range_clock(timeout_ptr, 0, HRTIMER_MODE_ABS, clock);
+ } while (ret < 0);
+ __set_current_state(TASK_RUNNING);
+
+ return ret;
+}
+
+/*
+ * Allocate and initialize the ntsync_q structure, but do not queue us yet.
+ */
+static int setup_wait(struct ntsync_device *dev,
+ const struct ntsync_wait_args *args,
+ struct ntsync_q **ret_q)
+{
+ const __u32 count = args->count;
+ int fds[NTSYNC_MAX_WAIT_COUNT];
+ struct ntsync_q *q;
+ __u32 i, j;
+
+ if (args->pad[0] || args->pad[1] || args->pad[2] || (args->flags & ~NTSYNC_WAIT_REALTIME))
+ return -EINVAL;
+
+ if (args->count > NTSYNC_MAX_WAIT_COUNT)
+ return -EINVAL;
+
+ if (copy_from_user(fds, u64_to_user_ptr(args->objs),
+ array_size(count, sizeof(*fds))))
+ return -EFAULT;
+
+ q = kmalloc(struct_size(q, entries, count), GFP_KERNEL);
+ if (!q)
+ return -ENOMEM;
+ q->task = current;
+ atomic_set(&q->signaled, -1);
+ q->count = count;
+
+ for (i = 0; i < count; i++) {
+ struct ntsync_q_entry *entry = &q->entries[i];
+ struct ntsync_obj *obj = get_obj(dev, fds[i]);
+
+ if (!obj)
+ goto err;
+
+ entry->obj = obj;
+ entry->q = q;
+ entry->index = i;
+ }
+
+ *ret_q = q;
+ return 0;
+
+err:
+ for (j = 0; j < i; j++)
+ put_obj(q->entries[j].obj);
+ kfree(q);
+ return -EINVAL;
+}
+
+static void try_wake_any_obj(struct ntsync_obj *obj)
+{
+ switch (obj->type) {
+ case NTSYNC_TYPE_SEM:
+ try_wake_any_sem(obj);
+ break;
+ }
+}
+
+static int ntsync_wait_any(struct ntsync_device *dev, void __user *argp)
+{
+ struct ntsync_wait_args args;
+ struct ntsync_q *q;
+ int signaled;
+ __u32 i;
+ int ret;
+
+ if (copy_from_user(&args, argp, sizeof(args)))
+ return -EFAULT;
+
+ ret = setup_wait(dev, &args, &q);
+ if (ret < 0)
+ return ret;
+
+ /* queue ourselves */
+
+ for (i = 0; i < args.count; i++) {
+ struct ntsync_q_entry *entry = &q->entries[i];
+ struct ntsync_obj *obj = entry->obj;
+
+ spin_lock(&obj->lock);
+ list_add_tail(&entry->node, &obj->any_waiters);
+ spin_unlock(&obj->lock);
+ }
+
+ /* check if we are already signaled */
+
+ for (i = 0; i < args.count; i++) {
+ struct ntsync_obj *obj = q->entries[i].obj;
+
+ if (atomic_read(&q->signaled) != -1)
+ break;
+
+ spin_lock(&obj->lock);
+ try_wake_any_obj(obj);
+ spin_unlock(&obj->lock);
+ }
+
+ /* sleep */
+
+ ret = ntsync_schedule(q, &args);
+
+ /* and finally, unqueue */
+
+ for (i = 0; i < args.count; i++) {
+ struct ntsync_q_entry *entry = &q->entries[i];
+ struct ntsync_obj *obj = entry->obj;
+
+ spin_lock(&obj->lock);
+ list_del(&entry->node);
+ spin_unlock(&obj->lock);
+
+ put_obj(obj);
+ }
+
+ signaled = atomic_read(&q->signaled);
+ if (signaled != -1) {
+ struct ntsync_wait_args __user *user_args = argp;
+
+ /* even if we caught a signal, we need to communicate success */
+ ret = 0;
+
+ if (put_user(signaled, &user_args->index))
+ ret = -EFAULT;
+ } else if (!ret) {
+ ret = -ETIMEDOUT;
+ }
+
+ kfree(q);
+ return ret;
+}
+
static int ntsync_char_open(struct inode *inode, struct file *file)
{
struct ntsync_device *dev;
@@ -218,6 +461,8 @@ static long ntsync_char_ioctl(struct fil
switch (cmd) {
case NTSYNC_IOC_CREATE_SEM:
return ntsync_create_sem(dev, argp);
+ case NTSYNC_IOC_WAIT_ANY:
+ return ntsync_wait_any(dev, argp);
default:
return -ENOIOCTLCMD;
}
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -15,7 +15,21 @@ struct ntsync_sem_args {
__u32 max;
};
+#define NTSYNC_WAIT_REALTIME 0x1
+
+struct ntsync_wait_args {
+ __u64 timeout;
+ __u64 objs;
+ __u32 count;
+ __u32 index;
+ __u32 flags;
+ __u32 pad[3];
+};
+
+#define NTSYNC_MAX_WAIT_COUNT 64
+
#define NTSYNC_IOC_CREATE_SEM _IOW ('N', 0x80, struct ntsync_sem_args)
+#define NTSYNC_IOC_WAIT_ANY _IOWR('N', 0x82, struct ntsync_wait_args)
#define NTSYNC_IOC_SEM_RELEASE _IOWR('N', 0x81, __u32)

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@@ -0,0 +1,533 @@
From 6c1dac87ff835a48a067fe75bd0a6965921dac78 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:45 -0600
Subject: ntsync: Introduce NTSYNC_IOC_WAIT_ALL.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
This is similar to NTSYNC_IOC_WAIT_ANY, but waits until all of the objects are
simultaneously signaled, and then acquires all of them as a single atomic
operation.
Because acquisition of multiple objects is atomic, some complex locking is
required. We cannot simply spin-lock multiple objects simultaneously, as that
may disable preëmption for a problematically long time.
Instead, modifying any object which may be involved in a wait-all operation takes
a device-wide sleeping mutex, "wait_all_lock", instead of the normal object
spinlock.
Because wait-for-all is a rare operation, in order to optimize wait-for-any,
this lock is only taken when necessary. "all_hint" is used to mark objects which
are involved in a wait-for-all operation, and if an object is not, only its
spinlock is taken.
The locking scheme used here was written by Peter Zijlstra.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 336 ++++++++++++++++++++++++++++++++++--
include/uapi/linux/ntsync.h | 1 +
2 files changed, 323 insertions(+), 14 deletions(-)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -13,6 +13,7 @@
#include <linux/ktime.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/overflow.h>
#include <linux/sched.h>
#include <linux/sched/signal.h>
@@ -41,6 +42,7 @@ enum ntsync_type {
struct ntsync_obj {
spinlock_t lock;
+ int dev_locked;
enum ntsync_type type;
@@ -55,7 +57,30 @@ struct ntsync_obj {
} sem;
} u;
+ /*
+ * any_waiters is protected by the object lock, but all_waiters is
+ * protected by the device wait_all_lock.
+ */
struct list_head any_waiters;
+ struct list_head all_waiters;
+
+ /*
+ * Hint describing how many tasks are queued on this object in a
+ * wait-all operation.
+ *
+ * Any time we do a wake, we may need to wake "all" waiters as well as
+ * "any" waiters. In order to atomically wake "all" waiters, we must
+ * lock all of the objects, and that means grabbing the wait_all_lock
+ * below (and, due to lock ordering rules, before locking this object).
+ * However, wait-all is a rare operation, and grabbing the wait-all
+ * lock for every wake would create unnecessary contention.
+ * Therefore we first check whether all_hint is zero, and, if it is,
+ * we skip trying to wake "all" waiters.
+ *
+ * Since wait requests must originate from user-space threads, we're
+ * limited here by PID_MAX_LIMIT, so there's no risk of overflow.
+ */
+ atomic_t all_hint;
};
struct ntsync_q_entry {
@@ -75,19 +100,198 @@ struct ntsync_q {
*/
atomic_t signaled;
+ bool all;
__u32 count;
struct ntsync_q_entry entries[];
};
struct ntsync_device {
+ /*
+ * Wait-all operations must atomically grab all objects, and be totally
+ * ordered with respect to each other and wait-any operations.
+ * If one thread is trying to acquire several objects, another thread
+ * cannot touch the object at the same time.
+ *
+ * This device-wide lock is used to serialize wait-for-all
+ * operations, and operations on an object that is involved in a
+ * wait-for-all.
+ */
+ struct mutex wait_all_lock;
+
struct file *file;
};
+/*
+ * Single objects are locked using obj->lock.
+ *
+ * Multiple objects are 'locked' while holding dev->wait_all_lock.
+ * In this case however, individual objects are not locked by holding
+ * obj->lock, but by setting obj->dev_locked.
+ *
+ * This means that in order to lock a single object, the sequence is slightly
+ * more complicated than usual. Specifically it needs to check obj->dev_locked
+ * after acquiring obj->lock, if set, it needs to drop the lock and acquire
+ * dev->wait_all_lock in order to serialize against the multi-object operation.
+ */
+
+static void dev_lock_obj(struct ntsync_device *dev, struct ntsync_obj *obj)
+{
+ lockdep_assert_held(&dev->wait_all_lock);
+ lockdep_assert(obj->dev == dev);
+ spin_lock(&obj->lock);
+ /*
+ * By setting obj->dev_locked inside obj->lock, it is ensured that
+ * anyone holding obj->lock must see the value.
+ */
+ obj->dev_locked = 1;
+ spin_unlock(&obj->lock);
+}
+
+static void dev_unlock_obj(struct ntsync_device *dev, struct ntsync_obj *obj)
+{
+ lockdep_assert_held(&dev->wait_all_lock);
+ lockdep_assert(obj->dev == dev);
+ spin_lock(&obj->lock);
+ obj->dev_locked = 0;
+ spin_unlock(&obj->lock);
+}
+
+static void obj_lock(struct ntsync_obj *obj)
+{
+ struct ntsync_device *dev = obj->dev;
+
+ for (;;) {
+ spin_lock(&obj->lock);
+ if (likely(!obj->dev_locked))
+ break;
+
+ spin_unlock(&obj->lock);
+ mutex_lock(&dev->wait_all_lock);
+ spin_lock(&obj->lock);
+ /*
+ * obj->dev_locked should be set and released under the same
+ * wait_all_lock section, since we now own this lock, it should
+ * be clear.
+ */
+ lockdep_assert(!obj->dev_locked);
+ spin_unlock(&obj->lock);
+ mutex_unlock(&dev->wait_all_lock);
+ }
+}
+
+static void obj_unlock(struct ntsync_obj *obj)
+{
+ spin_unlock(&obj->lock);
+}
+
+static bool ntsync_lock_obj(struct ntsync_device *dev, struct ntsync_obj *obj)
+{
+ bool all;
+
+ obj_lock(obj);
+ all = atomic_read(&obj->all_hint);
+ if (unlikely(all)) {
+ obj_unlock(obj);
+ mutex_lock(&dev->wait_all_lock);
+ dev_lock_obj(dev, obj);
+ }
+
+ return all;
+}
+
+static void ntsync_unlock_obj(struct ntsync_device *dev, struct ntsync_obj *obj, bool all)
+{
+ if (all) {
+ dev_unlock_obj(dev, obj);
+ mutex_unlock(&dev->wait_all_lock);
+ } else {
+ obj_unlock(obj);
+ }
+}
+
+#define ntsync_assert_held(obj) \
+ lockdep_assert((lockdep_is_held(&(obj)->lock) != LOCK_STATE_NOT_HELD) || \
+ ((lockdep_is_held(&(obj)->dev->wait_all_lock) != LOCK_STATE_NOT_HELD) && \
+ (obj)->dev_locked))
+
+static bool is_signaled(struct ntsync_obj *obj)
+{
+ ntsync_assert_held(obj);
+
+ switch (obj->type) {
+ case NTSYNC_TYPE_SEM:
+ return !!obj->u.sem.count;
+ }
+
+ WARN(1, "bad object type %#x\n", obj->type);
+ return false;
+}
+
+/*
+ * "locked_obj" is an optional pointer to an object which is already locked and
+ * should not be locked again. This is necessary so that changing an object's
+ * state and waking it can be a single atomic operation.
+ */
+static void try_wake_all(struct ntsync_device *dev, struct ntsync_q *q,
+ struct ntsync_obj *locked_obj)
+{
+ __u32 count = q->count;
+ bool can_wake = true;
+ int signaled = -1;
+ __u32 i;
+
+ lockdep_assert_held(&dev->wait_all_lock);
+ if (locked_obj)
+ lockdep_assert(locked_obj->dev_locked);
+
+ for (i = 0; i < count; i++) {
+ if (q->entries[i].obj != locked_obj)
+ dev_lock_obj(dev, q->entries[i].obj);
+ }
+
+ for (i = 0; i < count; i++) {
+ if (!is_signaled(q->entries[i].obj)) {
+ can_wake = false;
+ break;
+ }
+ }
+
+ if (can_wake && atomic_try_cmpxchg(&q->signaled, &signaled, 0)) {
+ for (i = 0; i < count; i++) {
+ struct ntsync_obj *obj = q->entries[i].obj;
+
+ switch (obj->type) {
+ case NTSYNC_TYPE_SEM:
+ obj->u.sem.count--;
+ break;
+ }
+ }
+ wake_up_process(q->task);
+ }
+
+ for (i = 0; i < count; i++) {
+ if (q->entries[i].obj != locked_obj)
+ dev_unlock_obj(dev, q->entries[i].obj);
+ }
+}
+
+static void try_wake_all_obj(struct ntsync_device *dev, struct ntsync_obj *obj)
+{
+ struct ntsync_q_entry *entry;
+
+ lockdep_assert_held(&dev->wait_all_lock);
+ lockdep_assert(obj->dev_locked);
+
+ list_for_each_entry(entry, &obj->all_waiters, node)
+ try_wake_all(dev, entry->q, obj);
+}
+
static void try_wake_any_sem(struct ntsync_obj *sem)
{
struct ntsync_q_entry *entry;
- lockdep_assert_held(&sem->lock);
+ ntsync_assert_held(sem);
+ lockdep_assert(sem->type == NTSYNC_TYPE_SEM);
list_for_each_entry(entry, &sem->any_waiters, node) {
struct ntsync_q *q = entry->q;
@@ -111,7 +315,7 @@ static int release_sem_state(struct ntsy
{
__u32 sum;
- lockdep_assert_held(&sem->lock);
+ ntsync_assert_held(sem);
if (check_add_overflow(sem->u.sem.count, count, &sum) ||
sum > sem->u.sem.max)
@@ -123,9 +327,11 @@ static int release_sem_state(struct ntsy
static int ntsync_sem_release(struct ntsync_obj *sem, void __user *argp)
{
+ struct ntsync_device *dev = sem->dev;
__u32 __user *user_args = argp;
__u32 prev_count;
__u32 args;
+ bool all;
int ret;
if (copy_from_user(&args, argp, sizeof(args)))
@@ -134,14 +340,17 @@ static int ntsync_sem_release(struct nts
if (sem->type != NTSYNC_TYPE_SEM)
return -EINVAL;
- spin_lock(&sem->lock);
+ all = ntsync_lock_obj(dev, sem);
prev_count = sem->u.sem.count;
- ret = post_sem_state(sem, args);
- if (!ret)
+ ret = release_sem_state(sem, args);
+ if (!ret) {
+ if (all)
+ try_wake_all_obj(dev, sem);
try_wake_any_sem(sem);
+ }
- spin_unlock(&sem->lock);
+ ntsync_unlock_obj(dev, sem, all);
if (!ret && put_user(prev_count, user_args))
ret = -EFAULT;
@@ -193,6 +402,8 @@ static struct ntsync_obj *ntsync_alloc_o
get_file(dev->file);
spin_lock_init(&obj->lock);
INIT_LIST_HEAD(&obj->any_waiters);
+ INIT_LIST_HEAD(&obj->all_waiters);
+ atomic_set(&obj->all_hint, 0);
return obj;
}
@@ -301,7 +512,7 @@ static int ntsync_schedule(const struct
* Allocate and initialize the ntsync_q structure, but do not queue us yet.
*/
static int setup_wait(struct ntsync_device *dev,
- const struct ntsync_wait_args *args,
+ const struct ntsync_wait_args *args, bool all,
struct ntsync_q **ret_q)
{
const __u32 count = args->count;
@@ -324,6 +535,7 @@ static int setup_wait(struct ntsync_devi
return -ENOMEM;
q->task = current;
atomic_set(&q->signaled, -1);
+ q->all = all;
q->count = count;
for (i = 0; i < count; i++) {
@@ -333,6 +545,16 @@ static int setup_wait(struct ntsync_devi
if (!obj)
goto err;
+ if (all) {
+ /* Check that the objects are all distinct. */
+ for (j = 0; j < i; j++) {
+ if (obj == q->entries[j].obj) {
+ put_obj(obj);
+ goto err;
+ }
+ }
+ }
+
entry->obj = obj;
entry->q = q;
entry->index = i;
@@ -362,13 +584,14 @@ static int ntsync_wait_any(struct ntsync
struct ntsync_wait_args args;
struct ntsync_q *q;
int signaled;
+ bool all;
__u32 i;
int ret;
if (copy_from_user(&args, argp, sizeof(args)))
return -EFAULT;
- ret = setup_wait(dev, &args, &q);
+ ret = setup_wait(dev, &args, false, &q);
if (ret < 0)
return ret;
@@ -378,9 +601,9 @@ static int ntsync_wait_any(struct ntsync
struct ntsync_q_entry *entry = &q->entries[i];
struct ntsync_obj *obj = entry->obj;
- spin_lock(&obj->lock);
+ all = ntsync_lock_obj(dev, obj);
list_add_tail(&entry->node, &obj->any_waiters);
- spin_unlock(&obj->lock);
+ ntsync_unlock_obj(dev, obj, all);
}
/* check if we are already signaled */
@@ -391,9 +614,9 @@ static int ntsync_wait_any(struct ntsync
if (atomic_read(&q->signaled) != -1)
break;
- spin_lock(&obj->lock);
+ all = ntsync_lock_obj(dev, obj);
try_wake_any_obj(obj);
- spin_unlock(&obj->lock);
+ ntsync_unlock_obj(dev, obj, all);
}
/* sleep */
@@ -406,13 +629,94 @@ static int ntsync_wait_any(struct ntsync
struct ntsync_q_entry *entry = &q->entries[i];
struct ntsync_obj *obj = entry->obj;
- spin_lock(&obj->lock);
+ all = ntsync_lock_obj(dev, obj);
list_del(&entry->node);
- spin_unlock(&obj->lock);
+ ntsync_unlock_obj(dev, obj, all);
+
+ put_obj(obj);
+ }
+
+ signaled = atomic_read(&q->signaled);
+ if (signaled != -1) {
+ struct ntsync_wait_args __user *user_args = argp;
+
+ /* even if we caught a signal, we need to communicate success */
+ ret = 0;
+
+ if (put_user(signaled, &user_args->index))
+ ret = -EFAULT;
+ } else if (!ret) {
+ ret = -ETIMEDOUT;
+ }
+
+ kfree(q);
+ return ret;
+}
+
+static int ntsync_wait_all(struct ntsync_device *dev, void __user *argp)
+{
+ struct ntsync_wait_args args;
+ struct ntsync_q *q;
+ int signaled;
+ __u32 i;
+ int ret;
+
+ if (copy_from_user(&args, argp, sizeof(args)))
+ return -EFAULT;
+
+ ret = setup_wait(dev, &args, true, &q);
+ if (ret < 0)
+ return ret;
+
+ /* queue ourselves */
+
+ mutex_lock(&dev->wait_all_lock);
+
+ for (i = 0; i < args.count; i++) {
+ struct ntsync_q_entry *entry = &q->entries[i];
+ struct ntsync_obj *obj = entry->obj;
+
+ atomic_inc(&obj->all_hint);
+
+ /*
+ * obj->all_waiters is protected by dev->wait_all_lock rather
+ * than obj->lock, so there is no need to acquire obj->lock
+ * here.
+ */
+ list_add_tail(&entry->node, &obj->all_waiters);
+ }
+
+ /* check if we are already signaled */
+
+ try_wake_all(dev, q, NULL);
+
+ mutex_unlock(&dev->wait_all_lock);
+
+ /* sleep */
+
+ ret = ntsync_schedule(q, &args);
+
+ /* and finally, unqueue */
+
+ mutex_lock(&dev->wait_all_lock);
+
+ for (i = 0; i < args.count; i++) {
+ struct ntsync_q_entry *entry = &q->entries[i];
+ struct ntsync_obj *obj = entry->obj;
+
+ /*
+ * obj->all_waiters is protected by dev->wait_all_lock rather
+ * than obj->lock, so there is no need to acquire it here.
+ */
+ list_del(&entry->node);
+
+ atomic_dec(&obj->all_hint);
put_obj(obj);
}
+ mutex_unlock(&dev->wait_all_lock);
+
signaled = atomic_read(&q->signaled);
if (signaled != -1) {
struct ntsync_wait_args __user *user_args = argp;
@@ -438,6 +742,8 @@ static int ntsync_char_open(struct inode
if (!dev)
return -ENOMEM;
+ mutex_init(&dev->wait_all_lock);
+
file->private_data = dev;
dev->file = file;
return nonseekable_open(inode, file);
@@ -461,6 +767,8 @@ static long ntsync_char_ioctl(struct fil
switch (cmd) {
case NTSYNC_IOC_CREATE_SEM:
return ntsync_create_sem(dev, argp);
+ case NTSYNC_IOC_WAIT_ALL:
+ return ntsync_wait_all(dev, argp);
case NTSYNC_IOC_WAIT_ANY:
return ntsync_wait_any(dev, argp);
default:
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -30,6 +30,7 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_CREATE_SEM _IOW ('N', 0x80, struct ntsync_sem_args)
#define NTSYNC_IOC_WAIT_ANY _IOWR('N', 0x82, struct ntsync_wait_args)
+#define NTSYNC_IOC_WAIT_ALL _IOWR('N', 0x83, struct ntsync_wait_args)
#define NTSYNC_IOC_SEM_RELEASE _IOWR('N', 0x81, __u32)

View File

@@ -0,0 +1,222 @@
From bcdeaefdc4b60e7845232c201427717df3a83277 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:46 -0600
Subject: ntsync: Introduce NTSYNC_IOC_CREATE_MUTEX.
This corresponds to the NT syscall NtCreateMutant().
An NT mutex is recursive, with a 32-bit recursion counter. When acquired via
NtWaitForMultipleObjects(), the recursion counter is incremented by one. The OS
records the thread which acquired it.
The OS records the thread which acquired it. However, in order to keep this
driver self-contained, the owning thread ID is managed by user-space, and passed
as a parameter to all relevant ioctls.
The initial owner and recursion count, if any, are specified when the mutex is
created.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 74 +++++++++++++++++++++++++++++++++++--
include/uapi/linux/ntsync.h | 9 ++++-
2 files changed, 79 insertions(+), 4 deletions(-)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -25,6 +25,7 @@
enum ntsync_type {
NTSYNC_TYPE_SEM,
+ NTSYNC_TYPE_MUTEX,
};
/*
@@ -55,6 +56,10 @@ struct ntsync_obj {
__u32 count;
__u32 max;
} sem;
+ struct {
+ __u32 count;
+ pid_t owner;
+ } mutex;
} u;
/*
@@ -92,6 +97,7 @@ struct ntsync_q_entry {
struct ntsync_q {
struct task_struct *task;
+ __u32 owner;
/*
* Protected via atomic_try_cmpxchg(). Only the thread that wins the
@@ -214,13 +220,17 @@ static void ntsync_unlock_obj(struct nts
((lockdep_is_held(&(obj)->dev->wait_all_lock) != LOCK_STATE_NOT_HELD) && \
(obj)->dev_locked))
-static bool is_signaled(struct ntsync_obj *obj)
+static bool is_signaled(struct ntsync_obj *obj, __u32 owner)
{
ntsync_assert_held(obj);
switch (obj->type) {
case NTSYNC_TYPE_SEM:
return !!obj->u.sem.count;
+ case NTSYNC_TYPE_MUTEX:
+ if (obj->u.mutex.owner && obj->u.mutex.owner != owner)
+ return false;
+ return obj->u.mutex.count < UINT_MAX;
}
WARN(1, "bad object type %#x\n", obj->type);
@@ -250,7 +260,7 @@ static void try_wake_all(struct ntsync_d
}
for (i = 0; i < count; i++) {
- if (!is_signaled(q->entries[i].obj)) {
+ if (!is_signaled(q->entries[i].obj, q->owner)) {
can_wake = false;
break;
}
@@ -264,6 +274,10 @@ static void try_wake_all(struct ntsync_d
case NTSYNC_TYPE_SEM:
obj->u.sem.count--;
break;
+ case NTSYNC_TYPE_MUTEX:
+ obj->u.mutex.count++;
+ obj->u.mutex.owner = q->owner;
+ break;
}
}
wake_up_process(q->task);
@@ -307,6 +321,30 @@ static void try_wake_any_sem(struct ntsy
}
}
+static void try_wake_any_mutex(struct ntsync_obj *mutex)
+{
+ struct ntsync_q_entry *entry;
+
+ ntsync_assert_held(mutex);
+ lockdep_assert(mutex->type == NTSYNC_TYPE_MUTEX);
+
+ list_for_each_entry(entry, &mutex->any_waiters, node) {
+ struct ntsync_q *q = entry->q;
+ int signaled = -1;
+
+ if (mutex->u.mutex.count == UINT_MAX)
+ break;
+ if (mutex->u.mutex.owner && mutex->u.mutex.owner != q->owner)
+ continue;
+
+ if (atomic_try_cmpxchg(&q->signaled, &signaled, entry->index)) {
+ mutex->u.mutex.count++;
+ mutex->u.mutex.owner = q->owner;
+ wake_up_process(q->task);
+ }
+ }
+}
+
/*
* Actually change the semaphore state, returning -EOVERFLOW if it is made
* invalid.
@@ -451,6 +489,30 @@ static int ntsync_create_sem(struct ntsy
return fd;
}
+static int ntsync_create_mutex(struct ntsync_device *dev, void __user *argp)
+{
+ struct ntsync_mutex_args args;
+ struct ntsync_obj *mutex;
+ int fd;
+
+ if (copy_from_user(&args, argp, sizeof(args)))
+ return -EFAULT;
+
+ if (!args.owner != !args.count)
+ return -EINVAL;
+
+ mutex = ntsync_alloc_obj(dev, NTSYNC_TYPE_MUTEX);
+ if (!mutex)
+ return -ENOMEM;
+ mutex->u.mutex.count = args.count;
+ mutex->u.mutex.owner = args.owner;
+ fd = ntsync_obj_get_fd(mutex);
+ if (fd < 0)
+ kfree(mutex);
+
+ return fd;
+}
+
static struct ntsync_obj *get_obj(struct ntsync_device *dev, int fd)
{
struct file *file = fget(fd);
@@ -520,7 +582,7 @@ static int setup_wait(struct ntsync_devi
struct ntsync_q *q;
__u32 i, j;
- if (args->pad[0] || args->pad[1] || args->pad[2] || (args->flags & ~NTSYNC_WAIT_REALTIME))
+ if (args->pad[0] || args->pad[1] || (args->flags & ~NTSYNC_WAIT_REALTIME))
return -EINVAL;
if (args->count > NTSYNC_MAX_WAIT_COUNT)
@@ -534,6 +596,7 @@ static int setup_wait(struct ntsync_devi
if (!q)
return -ENOMEM;
q->task = current;
+ q->owner = args->owner;
atomic_set(&q->signaled, -1);
q->all = all;
q->count = count;
@@ -576,6 +639,9 @@ static void try_wake_any_obj(struct ntsy
case NTSYNC_TYPE_SEM:
try_wake_any_sem(obj);
break;
+ case NTSYNC_TYPE_MUTEX:
+ try_wake_any_mutex(obj);
+ break;
}
}
@@ -765,6 +831,8 @@ static long ntsync_char_ioctl(struct fil
void __user *argp = (void __user *)parm;
switch (cmd) {
+ case NTSYNC_IOC_CREATE_MUTEX:
+ return ntsync_create_mutex(dev, argp);
case NTSYNC_IOC_CREATE_SEM:
return ntsync_create_sem(dev, argp);
case NTSYNC_IOC_WAIT_ALL:
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -15,6 +15,11 @@ struct ntsync_sem_args {
__u32 max;
};
+struct ntsync_mutex_args {
+ __u32 owner;
+ __u32 count;
+};
+
#define NTSYNC_WAIT_REALTIME 0x1
struct ntsync_wait_args {
@@ -23,7 +28,8 @@ struct ntsync_wait_args {
__u32 count;
__u32 index;
__u32 flags;
- __u32 pad[3];
+ __u32 owner;
+ __u32 pad[2];
};
#define NTSYNC_MAX_WAIT_COUNT 64
@@ -31,6 +37,7 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_CREATE_SEM _IOW ('N', 0x80, struct ntsync_sem_args)
#define NTSYNC_IOC_WAIT_ANY _IOWR('N', 0x82, struct ntsync_wait_args)
#define NTSYNC_IOC_WAIT_ALL _IOWR('N', 0x83, struct ntsync_wait_args)
+#define NTSYNC_IOC_CREATE_MUTEX _IOW ('N', 0x84, struct ntsync_mutex_args)
#define NTSYNC_IOC_SEM_RELEASE _IOWR('N', 0x81, __u32)

View File

@@ -0,0 +1,95 @@
From e349279c9dc7fc2136a764a16074a90ef3039f38 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:47 -0600
Subject: ntsync: Introduce NTSYNC_IOC_MUTEX_UNLOCK.
This corresponds to the NT syscall NtReleaseMutant().
This syscall decrements the mutex's recursion count by one, and returns the
previous value. If the mutex is not owned by the current task, the function
instead fails and returns -EPERM.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 53 +++++++++++++++++++++++++++++++++++++
include/uapi/linux/ntsync.h | 1 +
2 files changed, 54 insertions(+)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -396,6 +396,57 @@ static int ntsync_sem_release(struct nts
return ret;
}
+/*
+ * Actually change the mutex state, returning -EPERM if not the owner.
+ */
+static int unlock_mutex_state(struct ntsync_obj *mutex,
+ const struct ntsync_mutex_args *args)
+{
+ ntsync_assert_held(mutex);
+
+ if (mutex->u.mutex.owner != args->owner)
+ return -EPERM;
+
+ if (!--mutex->u.mutex.count)
+ mutex->u.mutex.owner = 0;
+ return 0;
+}
+
+static int ntsync_mutex_unlock(struct ntsync_obj *mutex, void __user *argp)
+{
+ struct ntsync_mutex_args __user *user_args = argp;
+ struct ntsync_device *dev = mutex->dev;
+ struct ntsync_mutex_args args;
+ __u32 prev_count;
+ bool all;
+ int ret;
+
+ if (copy_from_user(&args, argp, sizeof(args)))
+ return -EFAULT;
+ if (!args.owner)
+ return -EINVAL;
+
+ if (mutex->type != NTSYNC_TYPE_MUTEX)
+ return -EINVAL;
+
+ all = ntsync_lock_obj(dev, mutex);
+
+ prev_count = mutex->u.mutex.count;
+ ret = unlock_mutex_state(mutex, &args);
+ if (!ret) {
+ if (all)
+ try_wake_all_obj(dev, mutex);
+ try_wake_any_mutex(mutex);
+ }
+
+ ntsync_unlock_obj(dev, mutex, all);
+
+ if (!ret && put_user(prev_count, &user_args->count))
+ ret = -EFAULT;
+
+ return ret;
+}
+
static int ntsync_obj_release(struct inode *inode, struct file *file)
{
struct ntsync_obj *obj = file->private_data;
@@ -415,6 +466,8 @@ static long ntsync_obj_ioctl(struct file
switch (cmd) {
case NTSYNC_IOC_SEM_RELEASE:
return ntsync_sem_release(obj, argp);
+ case NTSYNC_IOC_MUTEX_UNLOCK:
+ return ntsync_mutex_unlock(obj, argp);
default:
return -ENOIOCTLCMD;
}
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -40,5 +40,6 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_CREATE_MUTEX _IOW ('N', 0x84, struct ntsync_mutex_args)
#define NTSYNC_IOC_SEM_RELEASE _IOWR('N', 0x81, __u32)
+#define NTSYNC_IOC_MUTEX_UNLOCK _IOWR('N', 0x85, struct ntsync_mutex_args)
#endif

View File

@@ -0,0 +1,156 @@
From ebb60a10ac3c6b28ba7a46aa67b279d41ad9356d Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:48 -0600
Subject: ntsync: Introduce NTSYNC_IOC_MUTEX_KILL.
This does not correspond to any NT syscall. Rather, when a thread dies, it
should be called by the NT emulator for each mutex, with the TID of the dying
thread.
NT mutexes are robust (in the pthread sense). When an NT thread dies, any
mutexes it owned are immediately released. Acquisition of those mutexes by other
threads will return a special value indicating that the mutex was abandoned,
like EOWNERDEAD returned from pthread_mutex_lock(), and EOWNERDEAD is indeed
used here for that purpose.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 61 +++++++++++++++++++++++++++++++++++--
include/uapi/linux/ntsync.h | 1 +
2 files changed, 60 insertions(+), 2 deletions(-)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -59,6 +59,7 @@ struct ntsync_obj {
struct {
__u32 count;
pid_t owner;
+ bool ownerdead;
} mutex;
} u;
@@ -107,6 +108,7 @@ struct ntsync_q {
atomic_t signaled;
bool all;
+ bool ownerdead;
__u32 count;
struct ntsync_q_entry entries[];
};
@@ -275,6 +277,9 @@ static void try_wake_all(struct ntsync_d
obj->u.sem.count--;
break;
case NTSYNC_TYPE_MUTEX:
+ if (obj->u.mutex.ownerdead)
+ q->ownerdead = true;
+ obj->u.mutex.ownerdead = false;
obj->u.mutex.count++;
obj->u.mutex.owner = q->owner;
break;
@@ -338,6 +343,9 @@ static void try_wake_any_mutex(struct nt
continue;
if (atomic_try_cmpxchg(&q->signaled, &signaled, entry->index)) {
+ if (mutex->u.mutex.ownerdead)
+ q->ownerdead = true;
+ mutex->u.mutex.ownerdead = false;
mutex->u.mutex.count++;
mutex->u.mutex.owner = q->owner;
wake_up_process(q->task);
@@ -447,6 +455,52 @@ static int ntsync_mutex_unlock(struct nt
return ret;
}
+/*
+ * Actually change the mutex state to mark its owner as dead,
+ * returning -EPERM if not the owner.
+ */
+static int kill_mutex_state(struct ntsync_obj *mutex, __u32 owner)
+{
+ ntsync_assert_held(mutex);
+
+ if (mutex->u.mutex.owner != owner)
+ return -EPERM;
+
+ mutex->u.mutex.ownerdead = true;
+ mutex->u.mutex.owner = 0;
+ mutex->u.mutex.count = 0;
+ return 0;
+}
+
+static int ntsync_mutex_kill(struct ntsync_obj *mutex, void __user *argp)
+{
+ struct ntsync_device *dev = mutex->dev;
+ __u32 owner;
+ bool all;
+ int ret;
+
+ if (get_user(owner, (__u32 __user *)argp))
+ return -EFAULT;
+ if (!owner)
+ return -EINVAL;
+
+ if (mutex->type != NTSYNC_TYPE_MUTEX)
+ return -EINVAL;
+
+ all = ntsync_lock_obj(dev, mutex);
+
+ ret = kill_mutex_state(mutex, owner);
+ if (!ret) {
+ if (all)
+ try_wake_all_obj(dev, mutex);
+ try_wake_any_mutex(mutex);
+ }
+
+ ntsync_unlock_obj(dev, mutex, all);
+
+ return ret;
+}
+
static int ntsync_obj_release(struct inode *inode, struct file *file)
{
struct ntsync_obj *obj = file->private_data;
@@ -468,6 +522,8 @@ static long ntsync_obj_ioctl(struct file
return ntsync_sem_release(obj, argp);
case NTSYNC_IOC_MUTEX_UNLOCK:
return ntsync_mutex_unlock(obj, argp);
+ case NTSYNC_IOC_MUTEX_KILL:
+ return ntsync_mutex_kill(obj, argp);
default:
return -ENOIOCTLCMD;
}
@@ -652,6 +708,7 @@ static int setup_wait(struct ntsync_devi
q->owner = args->owner;
atomic_set(&q->signaled, -1);
q->all = all;
+ q->ownerdead = false;
q->count = count;
for (i = 0; i < count; i++) {
@@ -760,7 +817,7 @@ static int ntsync_wait_any(struct ntsync
struct ntsync_wait_args __user *user_args = argp;
/* even if we caught a signal, we need to communicate success */
- ret = 0;
+ ret = q->ownerdead ? -EOWNERDEAD : 0;
if (put_user(signaled, &user_args->index))
ret = -EFAULT;
@@ -841,7 +898,7 @@ static int ntsync_wait_all(struct ntsync
struct ntsync_wait_args __user *user_args = argp;
/* even if we caught a signal, we need to communicate success */
- ret = 0;
+ ret = q->ownerdead ? -EOWNERDEAD : 0;
if (put_user(signaled, &user_args->index))
ret = -EFAULT;
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -41,5 +41,6 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_SEM_RELEASE _IOWR('N', 0x81, __u32)
#define NTSYNC_IOC_MUTEX_UNLOCK _IOWR('N', 0x85, struct ntsync_mutex_args)
+#define NTSYNC_IOC_MUTEX_KILL _IOW ('N', 0x86, __u32)
#endif

View File

@@ -0,0 +1,162 @@
From f74c8259d49ea4c0e679902da9c7c95ec06ae65c Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:49 -0600
Subject: ntsync: Introduce NTSYNC_IOC_CREATE_EVENT.
This correspond to the NT syscall NtCreateEvent().
An NT event holds a single bit of state denoting whether it is signaled or
unsignaled.
There are two types of events: manual-reset and automatic-reset. When an
automatic-reset event is acquired via a wait function, its state is reset to
unsignaled. Manual-reset events are not affected by wait functions.
Whether the event is manual-reset, and its initial state, are specified at
creation time.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 59 +++++++++++++++++++++++++++++++++++++
include/uapi/linux/ntsync.h | 6 ++++
2 files changed, 65 insertions(+)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -26,6 +26,7 @@
enum ntsync_type {
NTSYNC_TYPE_SEM,
NTSYNC_TYPE_MUTEX,
+ NTSYNC_TYPE_EVENT,
};
/*
@@ -61,6 +62,10 @@ struct ntsync_obj {
pid_t owner;
bool ownerdead;
} mutex;
+ struct {
+ bool manual;
+ bool signaled;
+ } event;
} u;
/*
@@ -233,6 +238,8 @@ static bool is_signaled(struct ntsync_ob
if (obj->u.mutex.owner && obj->u.mutex.owner != owner)
return false;
return obj->u.mutex.count < UINT_MAX;
+ case NTSYNC_TYPE_EVENT:
+ return obj->u.event.signaled;
}
WARN(1, "bad object type %#x\n", obj->type);
@@ -283,6 +290,10 @@ static void try_wake_all(struct ntsync_d
obj->u.mutex.count++;
obj->u.mutex.owner = q->owner;
break;
+ case NTSYNC_TYPE_EVENT:
+ if (!obj->u.event.manual)
+ obj->u.event.signaled = false;
+ break;
}
}
wake_up_process(q->task);
@@ -353,6 +364,28 @@ static void try_wake_any_mutex(struct nt
}
}
+static void try_wake_any_event(struct ntsync_obj *event)
+{
+ struct ntsync_q_entry *entry;
+
+ ntsync_assert_held(event);
+ lockdep_assert(event->type == NTSYNC_TYPE_EVENT);
+
+ list_for_each_entry(entry, &event->any_waiters, node) {
+ struct ntsync_q *q = entry->q;
+ int signaled = -1;
+
+ if (!event->u.event.signaled)
+ break;
+
+ if (atomic_try_cmpxchg(&q->signaled, &signaled, entry->index)) {
+ if (!event->u.event.manual)
+ event->u.event.signaled = false;
+ wake_up_process(q->task);
+ }
+ }
+}
+
/*
* Actually change the semaphore state, returning -EOVERFLOW if it is made
* invalid.
@@ -622,6 +655,27 @@ static int ntsync_create_mutex(struct nt
return fd;
}
+static int ntsync_create_event(struct ntsync_device *dev, void __user *argp)
+{
+ struct ntsync_event_args args;
+ struct ntsync_obj *event;
+ int fd;
+
+ if (copy_from_user(&args, argp, sizeof(args)))
+ return -EFAULT;
+
+ event = ntsync_alloc_obj(dev, NTSYNC_TYPE_EVENT);
+ if (!event)
+ return -ENOMEM;
+ event->u.event.manual = args.manual;
+ event->u.event.signaled = args.signaled;
+ fd = ntsync_obj_get_fd(event);
+ if (fd < 0)
+ kfree(event);
+
+ return fd;
+}
+
static struct ntsync_obj *get_obj(struct ntsync_device *dev, int fd)
{
struct file *file = fget(fd);
@@ -752,6 +806,9 @@ static void try_wake_any_obj(struct ntsy
case NTSYNC_TYPE_MUTEX:
try_wake_any_mutex(obj);
break;
+ case NTSYNC_TYPE_EVENT:
+ try_wake_any_event(obj);
+ break;
}
}
@@ -941,6 +998,8 @@ static long ntsync_char_ioctl(struct fil
void __user *argp = (void __user *)parm;
switch (cmd) {
+ case NTSYNC_IOC_CREATE_EVENT:
+ return ntsync_create_event(dev, argp);
case NTSYNC_IOC_CREATE_MUTEX:
return ntsync_create_mutex(dev, argp);
case NTSYNC_IOC_CREATE_SEM:
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -20,6 +20,11 @@ struct ntsync_mutex_args {
__u32 count;
};
+struct ntsync_event_args {
+ __u32 manual;
+ __u32 signaled;
+};
+
#define NTSYNC_WAIT_REALTIME 0x1
struct ntsync_wait_args {
@@ -38,6 +43,7 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_WAIT_ANY _IOWR('N', 0x82, struct ntsync_wait_args)
#define NTSYNC_IOC_WAIT_ALL _IOWR('N', 0x83, struct ntsync_wait_args)
#define NTSYNC_IOC_CREATE_MUTEX _IOW ('N', 0x84, struct ntsync_mutex_args)
+#define NTSYNC_IOC_CREATE_EVENT _IOW ('N', 0x87, struct ntsync_event_args)
#define NTSYNC_IOC_SEM_RELEASE _IOWR('N', 0x81, __u32)
#define NTSYNC_IOC_MUTEX_UNLOCK _IOWR('N', 0x85, struct ntsync_mutex_args)

View File

@@ -0,0 +1,67 @@
From bf60db9cfeccc8f92636b6dcf2eccd7fcd8d84f3 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:50 -0600
Subject: ntsync: Introduce NTSYNC_IOC_EVENT_SET.
This corresponds to the NT syscall NtSetEvent().
This sets the event to the signaled state, and returns its previous state.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 27 +++++++++++++++++++++++++++
include/uapi/linux/ntsync.h | 1 +
2 files changed, 28 insertions(+)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -534,6 +534,31 @@ static int ntsync_mutex_kill(struct ntsy
return ret;
}
+static int ntsync_event_set(struct ntsync_obj *event, void __user *argp)
+{
+ struct ntsync_device *dev = event->dev;
+ __u32 prev_state;
+ bool all;
+
+ if (event->type != NTSYNC_TYPE_EVENT)
+ return -EINVAL;
+
+ all = ntsync_lock_obj(dev, event);
+
+ prev_state = event->u.event.signaled;
+ event->u.event.signaled = true;
+ if (all)
+ try_wake_all_obj(dev, event);
+ try_wake_any_event(event);
+
+ ntsync_unlock_obj(dev, event, all);
+
+ if (put_user(prev_state, (__u32 __user *)argp))
+ return -EFAULT;
+
+ return 0;
+}
+
static int ntsync_obj_release(struct inode *inode, struct file *file)
{
struct ntsync_obj *obj = file->private_data;
@@ -557,6 +582,8 @@ static long ntsync_obj_ioctl(struct file
return ntsync_mutex_unlock(obj, argp);
case NTSYNC_IOC_MUTEX_KILL:
return ntsync_mutex_kill(obj, argp);
+ case NTSYNC_IOC_EVENT_SET:
+ return ntsync_event_set(obj, argp);
default:
return -ENOIOCTLCMD;
}
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -48,5 +48,6 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_SEM_RELEASE _IOWR('N', 0x81, __u32)
#define NTSYNC_IOC_MUTEX_UNLOCK _IOWR('N', 0x85, struct ntsync_mutex_args)
#define NTSYNC_IOC_MUTEX_KILL _IOW ('N', 0x86, __u32)
+#define NTSYNC_IOC_EVENT_SET _IOR ('N', 0x88, __u32)
#endif

View File

@@ -0,0 +1,64 @@
From f2de3c99a840cac45446515dd268cb9d64f9f892 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:51 -0600
Subject: ntsync: Introduce NTSYNC_IOC_EVENT_RESET.
This corresponds to the NT syscall NtResetEvent().
This sets the event to the unsignaled state, and returns its previous state.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 24 ++++++++++++++++++++++++
include/uapi/linux/ntsync.h | 1 +
2 files changed, 25 insertions(+)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -559,6 +559,28 @@ static int ntsync_event_set(struct ntsyn
return 0;
}
+static int ntsync_event_reset(struct ntsync_obj *event, void __user *argp)
+{
+ struct ntsync_device *dev = event->dev;
+ __u32 prev_state;
+ bool all;
+
+ if (event->type != NTSYNC_TYPE_EVENT)
+ return -EINVAL;
+
+ all = ntsync_lock_obj(dev, event);
+
+ prev_state = event->u.event.signaled;
+ event->u.event.signaled = false;
+
+ ntsync_unlock_obj(dev, event, all);
+
+ if (put_user(prev_state, (__u32 __user *)argp))
+ return -EFAULT;
+
+ return 0;
+}
+
static int ntsync_obj_release(struct inode *inode, struct file *file)
{
struct ntsync_obj *obj = file->private_data;
@@ -584,6 +606,8 @@ static long ntsync_obj_ioctl(struct file
return ntsync_mutex_kill(obj, argp);
case NTSYNC_IOC_EVENT_SET:
return ntsync_event_set(obj, argp);
+ case NTSYNC_IOC_EVENT_RESET:
+ return ntsync_event_reset(obj, argp);
default:
return -ENOIOCTLCMD;
}
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -49,5 +49,6 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_MUTEX_UNLOCK _IOWR('N', 0x85, struct ntsync_mutex_args)
#define NTSYNC_IOC_MUTEX_KILL _IOW ('N', 0x86, __u32)
#define NTSYNC_IOC_EVENT_SET _IOR ('N', 0x88, __u32)
+#define NTSYNC_IOC_EVENT_RESET _IOR ('N', 0x89, __u32)
#endif

View File

@@ -0,0 +1,60 @@
From 50c791dde217f9fdc1785de77fa2ae888d6bdb4e Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:52 -0600
Subject: ntsync: Introduce NTSYNC_IOC_EVENT_PULSE.
This corresponds to the NT syscall NtPulseEvent().
This wakes up any waiters as if the event had been set, but does not set the
event, instead resetting it if it had been signalled. Thus, for a manual-reset
event, all waiters are woken, whereas for an auto-reset event, at most one
waiter is woken.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 8 ++++++--
include/uapi/linux/ntsync.h | 1 +
2 files changed, 7 insertions(+), 2 deletions(-)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -534,7 +534,7 @@ static int ntsync_mutex_kill(struct ntsy
return ret;
}
-static int ntsync_event_set(struct ntsync_obj *event, void __user *argp)
+static int ntsync_event_set(struct ntsync_obj *event, void __user *argp, bool pulse)
{
struct ntsync_device *dev = event->dev;
__u32 prev_state;
@@ -550,6 +550,8 @@ static int ntsync_event_set(struct ntsyn
if (all)
try_wake_all_obj(dev, event);
try_wake_any_event(event);
+ if (pulse)
+ event->u.event.signaled = false;
ntsync_unlock_obj(dev, event, all);
@@ -605,9 +607,11 @@ static long ntsync_obj_ioctl(struct file
case NTSYNC_IOC_MUTEX_KILL:
return ntsync_mutex_kill(obj, argp);
case NTSYNC_IOC_EVENT_SET:
- return ntsync_event_set(obj, argp);
+ return ntsync_event_set(obj, argp, false);
case NTSYNC_IOC_EVENT_RESET:
return ntsync_event_reset(obj, argp);
+ case NTSYNC_IOC_EVENT_PULSE:
+ return ntsync_event_set(obj, argp, true);
default:
return -ENOIOCTLCMD;
}
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -50,5 +50,6 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_MUTEX_KILL _IOW ('N', 0x86, __u32)
#define NTSYNC_IOC_EVENT_SET _IOR ('N', 0x88, __u32)
#define NTSYNC_IOC_EVENT_RESET _IOR ('N', 0x89, __u32)
+#define NTSYNC_IOC_EVENT_PULSE _IOR ('N', 0x8a, __u32)
#endif

View File

@@ -0,0 +1,64 @@
From 248013d9877d47dc5219344268c10b62de1f52f2 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:53 -0600
Subject: ntsync: Introduce NTSYNC_IOC_SEM_READ.
This corresponds to the NT syscall NtQuerySemaphore().
This returns the current count and maximum count of the semaphore.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 24 ++++++++++++++++++++++++
include/uapi/linux/ntsync.h | 1 +
2 files changed, 25 insertions(+)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -583,6 +583,28 @@ static int ntsync_event_reset(struct nts
return 0;
}
+static int ntsync_sem_read(struct ntsync_obj *sem, void __user *argp)
+{
+ struct ntsync_sem_args __user *user_args = argp;
+ struct ntsync_device *dev = sem->dev;
+ struct ntsync_sem_args args;
+ bool all;
+
+ if (sem->type != NTSYNC_TYPE_SEM)
+ return -EINVAL;
+
+ all = ntsync_lock_obj(dev, sem);
+
+ args.count = sem->u.sem.count;
+ args.max = sem->u.sem.max;
+
+ ntsync_unlock_obj(dev, sem, all);
+
+ if (copy_to_user(user_args, &args, sizeof(args)))
+ return -EFAULT;
+ return 0;
+}
+
static int ntsync_obj_release(struct inode *inode, struct file *file)
{
struct ntsync_obj *obj = file->private_data;
@@ -602,6 +624,8 @@ static long ntsync_obj_ioctl(struct file
switch (cmd) {
case NTSYNC_IOC_SEM_RELEASE:
return ntsync_sem_release(obj, argp);
+ case NTSYNC_IOC_SEM_READ:
+ return ntsync_sem_read(obj, argp);
case NTSYNC_IOC_MUTEX_UNLOCK:
return ntsync_mutex_unlock(obj, argp);
case NTSYNC_IOC_MUTEX_KILL:
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -51,5 +51,6 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_EVENT_SET _IOR ('N', 0x88, __u32)
#define NTSYNC_IOC_EVENT_RESET _IOR ('N', 0x89, __u32)
#define NTSYNC_IOC_EVENT_PULSE _IOR ('N', 0x8a, __u32)
+#define NTSYNC_IOC_SEM_READ _IOR ('N', 0x8b, struct ntsync_sem_args)
#endif

View File

@@ -0,0 +1,66 @@
From 8fc7a993fd8bc6b1a09b4b965bee7d16bb2156cc Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:54 -0600
Subject: ntsync: Introduce NTSYNC_IOC_MUTEX_READ.
This corresponds to the NT syscall NtQueryMutant().
This returns the recursion count, owner, and abandoned state of the mutex.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 26 ++++++++++++++++++++++++++
include/uapi/linux/ntsync.h | 1 +
2 files changed, 27 insertions(+)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -605,6 +605,30 @@ static int ntsync_sem_read(struct ntsync
return 0;
}
+static int ntsync_mutex_read(struct ntsync_obj *mutex, void __user *argp)
+{
+ struct ntsync_mutex_args __user *user_args = argp;
+ struct ntsync_device *dev = mutex->dev;
+ struct ntsync_mutex_args args;
+ bool all;
+ int ret;
+
+ if (mutex->type != NTSYNC_TYPE_MUTEX)
+ return -EINVAL;
+
+ all = ntsync_lock_obj(dev, mutex);
+
+ args.count = mutex->u.mutex.count;
+ args.owner = mutex->u.mutex.owner;
+ ret = mutex->u.mutex.ownerdead ? -EOWNERDEAD : 0;
+
+ ntsync_unlock_obj(dev, mutex, all);
+
+ if (copy_to_user(user_args, &args, sizeof(args)))
+ return -EFAULT;
+ return ret;
+}
+
static int ntsync_obj_release(struct inode *inode, struct file *file)
{
struct ntsync_obj *obj = file->private_data;
@@ -630,6 +654,8 @@ static long ntsync_obj_ioctl(struct file
return ntsync_mutex_unlock(obj, argp);
case NTSYNC_IOC_MUTEX_KILL:
return ntsync_mutex_kill(obj, argp);
+ case NTSYNC_IOC_MUTEX_READ:
+ return ntsync_mutex_read(obj, argp);
case NTSYNC_IOC_EVENT_SET:
return ntsync_event_set(obj, argp, false);
case NTSYNC_IOC_EVENT_RESET:
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -52,5 +52,6 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_EVENT_RESET _IOR ('N', 0x89, __u32)
#define NTSYNC_IOC_EVENT_PULSE _IOR ('N', 0x8a, __u32)
#define NTSYNC_IOC_SEM_READ _IOR ('N', 0x8b, struct ntsync_sem_args)
+#define NTSYNC_IOC_MUTEX_READ _IOR ('N', 0x8c, struct ntsync_mutex_args)
#endif

View File

@@ -0,0 +1,64 @@
From aed34cc9c28dba5e3735d7c59e1970a32eefc5f4 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:55 -0600
Subject: ntsync: Introduce NTSYNC_IOC_EVENT_READ.
This corresponds to the NT syscall NtQueryEvent().
This returns the signaled state of the event and whether it is manual-reset.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 24 ++++++++++++++++++++++++
include/uapi/linux/ntsync.h | 1 +
2 files changed, 25 insertions(+)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -629,6 +629,28 @@ static int ntsync_mutex_read(struct ntsy
return ret;
}
+static int ntsync_event_read(struct ntsync_obj *event, void __user *argp)
+{
+ struct ntsync_event_args __user *user_args = argp;
+ struct ntsync_device *dev = event->dev;
+ struct ntsync_event_args args;
+ bool all;
+
+ if (event->type != NTSYNC_TYPE_EVENT)
+ return -EINVAL;
+
+ all = ntsync_lock_obj(dev, event);
+
+ args.manual = event->u.event.manual;
+ args.signaled = event->u.event.signaled;
+
+ ntsync_unlock_obj(dev, event, all);
+
+ if (copy_to_user(user_args, &args, sizeof(args)))
+ return -EFAULT;
+ return 0;
+}
+
static int ntsync_obj_release(struct inode *inode, struct file *file)
{
struct ntsync_obj *obj = file->private_data;
@@ -662,6 +684,8 @@ static long ntsync_obj_ioctl(struct file
return ntsync_event_reset(obj, argp);
case NTSYNC_IOC_EVENT_PULSE:
return ntsync_event_set(obj, argp, true);
+ case NTSYNC_IOC_EVENT_READ:
+ return ntsync_event_read(obj, argp);
default:
return -ENOIOCTLCMD;
}
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -53,5 +53,6 @@ struct ntsync_wait_args {
#define NTSYNC_IOC_EVENT_PULSE _IOR ('N', 0x8a, __u32)
#define NTSYNC_IOC_SEM_READ _IOR ('N', 0x8b, struct ntsync_sem_args)
#define NTSYNC_IOC_MUTEX_READ _IOR ('N', 0x8c, struct ntsync_mutex_args)
+#define NTSYNC_IOC_EVENT_READ _IOR ('N', 0x8d, struct ntsync_event_args)
#endif

View File

@@ -0,0 +1,187 @@
From 361a7fb848ba9cac87855cb68f9ab000ed1027be Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:34:56 -0600
Subject: ntsync: Introduce alertable waits.
NT waits can optionally be made "alertable". This is a special channel for
thread wakeup that is mildly similar to SIGIO. A thread has an internal single
bit of "alerted" state, and if a thread is alerted while an alertable wait, the
wait will return a special value, consume the "alerted" state, and will not
consume any of its objects.
Alerts are implemented using events; the user-space NT emulator is expected to
create an internal ntsync event for each thread and pass that event to wait
functions.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/ntsync.c | 70 ++++++++++++++++++++++++++++++++-----
include/uapi/linux/ntsync.h | 3 +-
2 files changed, 63 insertions(+), 10 deletions(-)
--- a/drivers/misc/ntsync.c
+++ b/drivers/misc/ntsync.c
@@ -869,22 +869,29 @@ static int setup_wait(struct ntsync_devi
const struct ntsync_wait_args *args, bool all,
struct ntsync_q **ret_q)
{
+ int fds[NTSYNC_MAX_WAIT_COUNT + 1];
const __u32 count = args->count;
- int fds[NTSYNC_MAX_WAIT_COUNT];
struct ntsync_q *q;
+ __u32 total_count;
__u32 i, j;
- if (args->pad[0] || args->pad[1] || (args->flags & ~NTSYNC_WAIT_REALTIME))
+ if (args->pad || (args->flags & ~NTSYNC_WAIT_REALTIME))
return -EINVAL;
if (args->count > NTSYNC_MAX_WAIT_COUNT)
return -EINVAL;
+ total_count = count;
+ if (args->alert)
+ total_count++;
+
if (copy_from_user(fds, u64_to_user_ptr(args->objs),
array_size(count, sizeof(*fds))))
return -EFAULT;
+ if (args->alert)
+ fds[count] = args->alert;
- q = kmalloc(struct_size(q, entries, count), GFP_KERNEL);
+ q = kmalloc(struct_size(q, entries, total_count), GFP_KERNEL);
if (!q)
return -ENOMEM;
q->task = current;
@@ -894,7 +901,7 @@ static int setup_wait(struct ntsync_devi
q->ownerdead = false;
q->count = count;
- for (i = 0; i < count; i++) {
+ for (i = 0; i < total_count; i++) {
struct ntsync_q_entry *entry = &q->entries[i];
struct ntsync_obj *obj = get_obj(dev, fds[i]);
@@ -944,10 +951,10 @@ static void try_wake_any_obj(struct ntsy
static int ntsync_wait_any(struct ntsync_device *dev, void __user *argp)
{
struct ntsync_wait_args args;
+ __u32 i, total_count;
struct ntsync_q *q;
int signaled;
bool all;
- __u32 i;
int ret;
if (copy_from_user(&args, argp, sizeof(args)))
@@ -957,9 +964,13 @@ static int ntsync_wait_any(struct ntsync
if (ret < 0)
return ret;
+ total_count = args.count;
+ if (args.alert)
+ total_count++;
+
/* queue ourselves */
- for (i = 0; i < args.count; i++) {
+ for (i = 0; i < total_count; i++) {
struct ntsync_q_entry *entry = &q->entries[i];
struct ntsync_obj *obj = entry->obj;
@@ -968,9 +979,15 @@ static int ntsync_wait_any(struct ntsync
ntsync_unlock_obj(dev, obj, all);
}
- /* check if we are already signaled */
+ /*
+ * Check if we are already signaled.
+ *
+ * Note that the API requires that normal objects are checked before
+ * the alert event. Hence we queue the alert event last, and check
+ * objects in order.
+ */
- for (i = 0; i < args.count; i++) {
+ for (i = 0; i < total_count; i++) {
struct ntsync_obj *obj = q->entries[i].obj;
if (atomic_read(&q->signaled) != -1)
@@ -987,7 +1004,7 @@ static int ntsync_wait_any(struct ntsync
/* and finally, unqueue */
- for (i = 0; i < args.count; i++) {
+ for (i = 0; i < total_count; i++) {
struct ntsync_q_entry *entry = &q->entries[i];
struct ntsync_obj *obj = entry->obj;
@@ -1047,6 +1064,14 @@ static int ntsync_wait_all(struct ntsync
*/
list_add_tail(&entry->node, &obj->all_waiters);
}
+ if (args.alert) {
+ struct ntsync_q_entry *entry = &q->entries[args.count];
+ struct ntsync_obj *obj = entry->obj;
+
+ dev_lock_obj(dev, obj);
+ list_add_tail(&entry->node, &obj->any_waiters);
+ dev_unlock_obj(dev, obj);
+ }
/* check if we are already signaled */
@@ -1054,6 +1079,21 @@ static int ntsync_wait_all(struct ntsync
mutex_unlock(&dev->wait_all_lock);
+ /*
+ * Check if the alert event is signaled, making sure to do so only
+ * after checking if the other objects are signaled.
+ */
+
+ if (args.alert) {
+ struct ntsync_obj *obj = q->entries[args.count].obj;
+
+ if (atomic_read(&q->signaled) == -1) {
+ bool all = ntsync_lock_obj(dev, obj);
+ try_wake_any_obj(obj);
+ ntsync_unlock_obj(dev, obj, all);
+ }
+ }
+
/* sleep */
ret = ntsync_schedule(q, &args);
@@ -1079,6 +1119,18 @@ static int ntsync_wait_all(struct ntsync
mutex_unlock(&dev->wait_all_lock);
+ if (args.alert) {
+ struct ntsync_q_entry *entry = &q->entries[args.count];
+ struct ntsync_obj *obj = entry->obj;
+ bool all;
+
+ all = ntsync_lock_obj(dev, obj);
+ list_del(&entry->node);
+ ntsync_unlock_obj(dev, obj, all);
+
+ put_obj(obj);
+ }
+
signaled = atomic_read(&q->signaled);
if (signaled != -1) {
struct ntsync_wait_args __user *user_args = argp;
--- a/include/uapi/linux/ntsync.h
+++ b/include/uapi/linux/ntsync.h
@@ -34,7 +34,8 @@ struct ntsync_wait_args {
__u32 index;
__u32 flags;
__u32 owner;
- __u32 pad[2];
+ __u32 alert;
+ __u32 pad;
};
#define NTSYNC_MAX_WAIT_COUNT 64

View File

@@ -0,0 +1,30 @@
From b240b27e5348d38acbc4a12f1dc762dd1845f391 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:35:09 -0600
Subject: maintainers: Add an entry for ntsync.
Add myself as maintainer, supported by CodeWeavers.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
MAINTAINERS | 9 +++++++++
1 file changed, 9 insertions(+)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -16486,6 +16486,15 @@ T: git https://github.com/Paragon-Softwa
F: Documentation/filesystems/ntfs3.rst
F: fs/ntfs3/
+NTSYNC SYNCHRONIZATION PRIMITIVE DRIVER
+M: Elizabeth Figura <zfigura@codeweavers.com>
+L: wine-devel@winehq.org
+S: Supported
+F: Documentation/userspace-api/ntsync.rst
+F: drivers/misc/ntsync.c
+F: include/uapi/linux/ntsync.h
+F: tools/testing/selftests/drivers/ntsync/
+
NUBUS SUBSYSTEM
M: Finn Thain <fthain@linux-m68k.org>
L: linux-m68k@lists.linux-m68k.org

View File

@@ -0,0 +1,413 @@
From 733e310bb840117593a0eb4726fa63b34fea9cc3 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:35:10 -0600
Subject: docs: ntsync: Add documentation for the ntsync uAPI.
Add an overall explanation of the driver architecture, and complete and precise
specification for its intended behaviour.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
Documentation/userspace-api/index.rst | 1 +
Documentation/userspace-api/ntsync.rst | 385 +++++++++++++++++++++++++
2 files changed, 386 insertions(+)
create mode 100644 Documentation/userspace-api/ntsync.rst
--- a/Documentation/userspace-api/index.rst
+++ b/Documentation/userspace-api/index.rst
@@ -63,6 +63,7 @@ Everything else
vduse
futex2
perf_ring_buffer
+ ntsync
.. only:: subproject and html
--- /dev/null
+++ b/Documentation/userspace-api/ntsync.rst
@@ -0,0 +1,385 @@
+===================================
+NT synchronization primitive driver
+===================================
+
+This page documents the user-space API for the ntsync driver.
+
+ntsync is a support driver for emulation of NT synchronization
+primitives by user-space NT emulators. It exists because implementation
+in user-space, using existing tools, cannot match Windows performance
+while offering accurate semantics. It is implemented entirely in
+software, and does not drive any hardware device.
+
+This interface is meant as a compatibility tool only, and should not
+be used for general synchronization. Instead use generic, versatile
+interfaces such as futex(2) and poll(2).
+
+Synchronization primitives
+==========================
+
+The ntsync driver exposes three types of synchronization primitives:
+semaphores, mutexes, and events.
+
+A semaphore holds a single volatile 32-bit counter, and a static 32-bit
+integer denoting the maximum value. It is considered signaled (that is,
+can be acquired without contention, or will wake up a waiting thread)
+when the counter is nonzero. The counter is decremented by one when a
+wait is satisfied. Both the initial and maximum count are established
+when the semaphore is created.
+
+A mutex holds a volatile 32-bit recursion count, and a volatile 32-bit
+identifier denoting its owner. A mutex is considered signaled when its
+owner is zero (indicating that it is not owned). The recursion count is
+incremented when a wait is satisfied, and ownership is set to the given
+identifier.
+
+A mutex also holds an internal flag denoting whether its previous owner
+has died; such a mutex is said to be abandoned. Owner death is not
+tracked automatically based on thread death, but rather must be
+communicated using ``NTSYNC_IOC_MUTEX_KILL``. An abandoned mutex is
+inherently considered unowned.
+
+Except for the "unowned" semantics of zero, the actual value of the
+owner identifier is not interpreted by the ntsync driver at all. The
+intended use is to store a thread identifier; however, the ntsync
+driver does not actually validate that a calling thread provides
+consistent or unique identifiers.
+
+An event is similar to a semaphore with a maximum count of one. It holds
+a volatile boolean state denoting whether it is signaled or not. There
+are two types of events, auto-reset and manual-reset. An auto-reset
+event is designaled when a wait is satisfied; a manual-reset event is
+not. The event type is specified when the event is created.
+
+Unless specified otherwise, all operations on an object are atomic and
+totally ordered with respect to other operations on the same object.
+
+Objects are represented by files. When all file descriptors to an
+object are closed, that object is deleted.
+
+Char device
+===========
+
+The ntsync driver creates a single char device /dev/ntsync. Each file
+description opened on the device represents a unique instance intended
+to back an individual NT virtual machine. Objects created by one ntsync
+instance may only be used with other objects created by the same
+instance.
+
+ioctl reference
+===============
+
+All operations on the device are done through ioctls. There are four
+structures used in ioctl calls::
+
+ struct ntsync_sem_args {
+ __u32 count;
+ __u32 max;
+ };
+
+ struct ntsync_mutex_args {
+ __u32 owner;
+ __u32 count;
+ };
+
+ struct ntsync_event_args {
+ __u32 signaled;
+ __u32 manual;
+ };
+
+ struct ntsync_wait_args {
+ __u64 timeout;
+ __u64 objs;
+ __u32 count;
+ __u32 owner;
+ __u32 index;
+ __u32 alert;
+ __u32 flags;
+ __u32 pad;
+ };
+
+Depending on the ioctl, members of the structure may be used as input,
+output, or not at all.
+
+The ioctls on the device file are as follows:
+
+.. c:macro:: NTSYNC_IOC_CREATE_SEM
+
+ Create a semaphore object. Takes a pointer to struct
+ :c:type:`ntsync_sem_args`, which is used as follows:
+
+ .. list-table::
+
+ * - ``count``
+ - Initial count of the semaphore.
+ * - ``max``
+ - Maximum count of the semaphore.
+
+ Fails with ``EINVAL`` if ``count`` is greater than ``max``.
+ On success, returns a file descriptor the created semaphore.
+
+.. c:macro:: NTSYNC_IOC_CREATE_MUTEX
+
+ Create a mutex object. Takes a pointer to struct
+ :c:type:`ntsync_mutex_args`, which is used as follows:
+
+ .. list-table::
+
+ * - ``count``
+ - Initial recursion count of the mutex.
+ * - ``owner``
+ - Initial owner of the mutex.
+
+ If ``owner`` is nonzero and ``count`` is zero, or if ``owner`` is
+ zero and ``count`` is nonzero, the function fails with ``EINVAL``.
+ On success, returns a file descriptor the created mutex.
+
+.. c:macro:: NTSYNC_IOC_CREATE_EVENT
+
+ Create an event object. Takes a pointer to struct
+ :c:type:`ntsync_event_args`, which is used as follows:
+
+ .. list-table::
+
+ * - ``signaled``
+ - If nonzero, the event is initially signaled, otherwise
+ nonsignaled.
+ * - ``manual``
+ - If nonzero, the event is a manual-reset event, otherwise
+ auto-reset.
+
+ On success, returns a file descriptor the created event.
+
+The ioctls on the individual objects are as follows:
+
+.. c:macro:: NTSYNC_IOC_SEM_POST
+
+ Post to a semaphore object. Takes a pointer to a 32-bit integer,
+ which on input holds the count to be added to the semaphore, and on
+ output contains its previous count.
+
+ If adding to the semaphore's current count would raise the latter
+ past the semaphore's maximum count, the ioctl fails with
+ ``EOVERFLOW`` and the semaphore is not affected. If raising the
+ semaphore's count causes it to become signaled, eligible threads
+ waiting on this semaphore will be woken and the semaphore's count
+ decremented appropriately.
+
+.. c:macro:: NTSYNC_IOC_MUTEX_UNLOCK
+
+ Release a mutex object. Takes a pointer to struct
+ :c:type:`ntsync_mutex_args`, which is used as follows:
+
+ .. list-table::
+
+ * - ``owner``
+ - Specifies the owner trying to release this mutex.
+ * - ``count``
+ - On output, contains the previous recursion count.
+
+ If ``owner`` is zero, the ioctl fails with ``EINVAL``. If ``owner``
+ is not the current owner of the mutex, the ioctl fails with
+ ``EPERM``.
+
+ The mutex's count will be decremented by one. If decrementing the
+ mutex's count causes it to become zero, the mutex is marked as
+ unowned and signaled, and eligible threads waiting on it will be
+ woken as appropriate.
+
+.. c:macro:: NTSYNC_IOC_SET_EVENT
+
+ Signal an event object. Takes a pointer to a 32-bit integer, which on
+ output contains the previous state of the event.
+
+ Eligible threads will be woken, and auto-reset events will be
+ designaled appropriately.
+
+.. c:macro:: NTSYNC_IOC_RESET_EVENT
+
+ Designal an event object. Takes a pointer to a 32-bit integer, which
+ on output contains the previous state of the event.
+
+.. c:macro:: NTSYNC_IOC_PULSE_EVENT
+
+ Wake threads waiting on an event object while leaving it in an
+ unsignaled state. Takes a pointer to a 32-bit integer, which on
+ output contains the previous state of the event.
+
+ A pulse operation can be thought of as a set followed by a reset,
+ performed as a single atomic operation. If two threads are waiting on
+ an auto-reset event which is pulsed, only one will be woken. If two
+ threads are waiting a manual-reset event which is pulsed, both will
+ be woken. However, in both cases, the event will be unsignaled
+ afterwards, and a simultaneous read operation will always report the
+ event as unsignaled.
+
+.. c:macro:: NTSYNC_IOC_READ_SEM
+
+ Read the current state of a semaphore object. Takes a pointer to
+ struct :c:type:`ntsync_sem_args`, which is used as follows:
+
+ .. list-table::
+
+ * - ``count``
+ - On output, contains the current count of the semaphore.
+ * - ``max``
+ - On output, contains the maximum count of the semaphore.
+
+.. c:macro:: NTSYNC_IOC_READ_MUTEX
+
+ Read the current state of a mutex object. Takes a pointer to struct
+ :c:type:`ntsync_mutex_args`, which is used as follows:
+
+ .. list-table::
+
+ * - ``owner``
+ - On output, contains the current owner of the mutex, or zero
+ if the mutex is not currently owned.
+ * - ``count``
+ - On output, contains the current recursion count of the mutex.
+
+ If the mutex is marked as abandoned, the function fails with
+ ``EOWNERDEAD``. In this case, ``count`` and ``owner`` are set to
+ zero.
+
+.. c:macro:: NTSYNC_IOC_READ_EVENT
+
+ Read the current state of an event object. Takes a pointer to struct
+ :c:type:`ntsync_event_args`, which is used as follows:
+
+ .. list-table::
+
+ * - ``signaled``
+ - On output, contains the current state of the event.
+ * - ``manual``
+ - On output, contains 1 if the event is a manual-reset event,
+ and 0 otherwise.
+
+.. c:macro:: NTSYNC_IOC_KILL_OWNER
+
+ Mark a mutex as unowned and abandoned if it is owned by the given
+ owner. Takes an input-only pointer to a 32-bit integer denoting the
+ owner. If the owner is zero, the ioctl fails with ``EINVAL``. If the
+ owner does not own the mutex, the function fails with ``EPERM``.
+
+ Eligible threads waiting on the mutex will be woken as appropriate
+ (and such waits will fail with ``EOWNERDEAD``, as described below).
+
+.. c:macro:: NTSYNC_IOC_WAIT_ANY
+
+ Poll on any of a list of objects, atomically acquiring at most one.
+ Takes a pointer to struct :c:type:`ntsync_wait_args`, which is
+ used as follows:
+
+ .. list-table::
+
+ * - ``timeout``
+ - Absolute timeout in nanoseconds. If ``NTSYNC_WAIT_REALTIME``
+ is set, the timeout is measured against the REALTIME clock;
+ otherwise it is measured against the MONOTONIC clock. If the
+ timeout is equal to or earlier than the current time, the
+ function returns immediately without sleeping. If ``timeout``
+ is U64_MAX, the function will sleep until an object is
+ signaled, and will not fail with ``ETIMEDOUT``.
+ * - ``objs``
+ - Pointer to an array of ``count`` file descriptors
+ (specified as an integer so that the structure has the same
+ size regardless of architecture). If any object is
+ invalid, the function fails with ``EINVAL``.
+ * - ``count``
+ - Number of objects specified in the ``objs`` array.
+ If greater than ``NTSYNC_MAX_WAIT_COUNT``, the function fails
+ with ``EINVAL``.
+ * - ``owner``
+ - Mutex owner identifier. If any object in ``objs`` is a mutex,
+ the ioctl will attempt to acquire that mutex on behalf of
+ ``owner``. If ``owner`` is zero, the ioctl fails with
+ ``EINVAL``.
+ * - ``index``
+ - On success, contains the index (into ``objs``) of the object
+ which was signaled. If ``alert`` was signaled instead,
+ this contains ``count``.
+ * - ``alert``
+ - Optional event object file descriptor. If nonzero, this
+ specifies an "alert" event object which, if signaled, will
+ terminate the wait. If nonzero, the identifier must point to a
+ valid event.
+ * - ``flags``
+ - Zero or more flags. Currently the only flag is
+ ``NTSYNC_WAIT_REALTIME``, which causes the timeout to be
+ measured against the REALTIME clock instead of MONOTONIC.
+ * - ``pad``
+ - Unused, must be set to zero.
+
+ This function attempts to acquire one of the given objects. If unable
+ to do so, it sleeps until an object becomes signaled, subsequently
+ acquiring it, or the timeout expires. In the latter case the ioctl
+ fails with ``ETIMEDOUT``. The function only acquires one object, even
+ if multiple objects are signaled.
+
+ A semaphore is considered to be signaled if its count is nonzero, and
+ is acquired by decrementing its count by one. A mutex is considered
+ to be signaled if it is unowned or if its owner matches the ``owner``
+ argument, and is acquired by incrementing its recursion count by one
+ and setting its owner to the ``owner`` argument. An auto-reset event
+ is acquired by designaling it; a manual-reset event is not affected
+ by acquisition.
+
+ Acquisition is atomic and totally ordered with respect to other
+ operations on the same object. If two wait operations (with different
+ ``owner`` identifiers) are queued on the same mutex, only one is
+ signaled. If two wait operations are queued on the same semaphore,
+ and a value of one is posted to it, only one is signaled.
+
+ If an abandoned mutex is acquired, the ioctl fails with
+ ``EOWNERDEAD``. Although this is a failure return, the function may
+ otherwise be considered successful. The mutex is marked as owned by
+ the given owner (with a recursion count of 1) and as no longer
+ abandoned, and ``index`` is still set to the index of the mutex.
+
+ The ``alert`` argument is an "extra" event which can terminate the
+ wait, independently of all other objects.
+
+ It is valid to pass the same object more than once, including by
+ passing the same event in the ``objs`` array and in ``alert``. If a
+ wakeup occurs due to that object being signaled, ``index`` is set to
+ the lowest index corresponding to that object.
+
+ The function may fail with ``EINTR`` if a signal is received.
+
+.. c:macro:: NTSYNC_IOC_WAIT_ALL
+
+ Poll on a list of objects, atomically acquiring all of them. Takes a
+ pointer to struct :c:type:`ntsync_wait_args`, which is used
+ identically to ``NTSYNC_IOC_WAIT_ANY``, except that ``index`` is
+ always filled with zero on success if not woken via alert.
+
+ This function attempts to simultaneously acquire all of the given
+ objects. If unable to do so, it sleeps until all objects become
+ simultaneously signaled, subsequently acquiring them, or the timeout
+ expires. In the latter case the ioctl fails with ``ETIMEDOUT`` and no
+ objects are modified.
+
+ Objects may become signaled and subsequently designaled (through
+ acquisition by other threads) while this thread is sleeping. Only
+ once all objects are simultaneously signaled does the ioctl acquire
+ them and return. The entire acquisition is atomic and totally ordered
+ with respect to other operations on any of the given objects.
+
+ If an abandoned mutex is acquired, the ioctl fails with
+ ``EOWNERDEAD``. Similarly to ``NTSYNC_IOC_WAIT_ANY``, all objects are
+ nevertheless marked as acquired. Note that if multiple mutex objects
+ are specified, there is no way to know which were marked as
+ abandoned.
+
+ As with "any" waits, the ``alert`` argument is an "extra" event which
+ can terminate the wait. Critically, however, an "all" wait will
+ succeed if all members in ``objs`` are signaled, *or* if ``alert`` is
+ signaled. In the latter case ``index`` will be set to ``count``. As
+ with "any" waits, if both conditions are filled, the former takes
+ priority, and objects in ``objs`` will be acquired.
+
+ Unlike ``NTSYNC_IOC_WAIT_ANY``, it is not valid to pass the same
+ object more than once, nor is it valid to pass the same object in
+ ``objs`` and in ``alert``. If this is attempted, the function fails
+ with ``EINVAL``.

View File

@@ -0,0 +1,25 @@
From 4871bb89577d78a3d55b44e47c3a4f677dbdc89b Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Fri, 13 Dec 2024 13:35:11 -0600
Subject: ntsync: No longer depend on BROKEN.
f5b335dc025cfee90957efa90dc72fada0d5abb4 ("misc: ntsync: mark driver as "broken"
to prevent from building") was committed to avoid the driver being used while
only part of its functionality was released. Since the rest of the functionality
has now been committed, revert this.
Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
drivers/misc/Kconfig | 1 -
1 file changed, 1 deletion(-)
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -517,7 +517,6 @@ config OPEN_DICE
config NTSYNC
tristate "NT synchronization primitive emulation"
- depends on BROKEN
help
This module provides kernel support for emulation of Windows NT
synchronization primitives. It is not a hardware driver.