#include <linux/aio_abi.h>
#include <linux/module.h>
#include <linux/syscalls.h>
+#include <linux/backing-dev.h>
+#include <linux/uio.h>
#define DEBUG 0
#include <linux/file.h>
#include <linux/mm.h>
#include <linux/mman.h>
+#include <linux/mmu_context.h>
#include <linux/slab.h>
#include <linux/timer.h>
#include <linux/aio.h>
#include <linux/highmem.h>
#include <linux/workqueue.h>
#include <linux/security.h>
+#include <linux/eventfd.h>
+#include <linux/blkdev.h>
+#include <linux/compat.h>
#include <asm/kmap_types.h>
#include <asm/uaccess.h>
-#include <asm/mmu_context.h>
#if DEBUG > 1
#define dprintk printk
#endif
/*------ sysctl variables----*/
-atomic_t aio_nr = ATOMIC_INIT(0); /* current system wide number of aio requests */
-unsigned aio_max_nr = 0x10000; /* system wide maximum number of aio requests */
+static DEFINE_SPINLOCK(aio_nr_lock);
+unsigned long aio_nr; /* current system wide number of aio requests */
+unsigned long aio_max_nr = 0x10000; /* system wide maximum number of aio requests */
/*----end sysctl variables---*/
-static kmem_cache_t *kiocb_cachep;
-static kmem_cache_t *kioctx_cachep;
+static struct kmem_cache *kiocb_cachep;
+static struct kmem_cache *kioctx_cachep;
static struct workqueue_struct *aio_wq;
/* Used for rare fput completion. */
-static void aio_fput_routine(void *);
-static DECLARE_WORK(fput_work, aio_fput_routine, NULL);
+static void aio_fput_routine(struct work_struct *);
+static DECLARE_WORK(fput_work, aio_fput_routine);
static DEFINE_SPINLOCK(fput_lock);
static LIST_HEAD(fput_head);
-static void aio_kick_handler(void *);
+static void aio_kick_handler(struct work_struct *);
static void aio_queue_work(struct kioctx *);
/* aio_setup
*/
static int __init aio_setup(void)
{
- kiocb_cachep = kmem_cache_create("kiocb", sizeof(struct kiocb),
- 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
- kioctx_cachep = kmem_cache_create("kioctx", sizeof(struct kioctx),
- 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
+ kiocb_cachep = KMEM_CACHE(kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
+ kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC);
- aio_wq = create_workqueue("aio");
+ aio_wq = alloc_workqueue("aio", 0, 1); /* used to limit concurrency */
+ BUG_ON(!aio_wq);
pr_debug("aio_setup: sizeof(struct page) = %d\n", (int)sizeof(struct page));
return 0;
}
+__initcall(aio_setup);
static void aio_free_ring(struct kioctx *ctx)
{
info->nr = 0;
info->ring_pages = info->internal_pages;
if (nr_pages > AIO_RING_PAGES) {
- info->ring_pages = kmalloc(sizeof(struct page *) * nr_pages, GFP_KERNEL);
+ info->ring_pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
if (!info->ring_pages)
return -ENOMEM;
- memset(info->ring_pages, 0, sizeof(struct page *) * nr_pages);
}
info->mmap_size = nr_pages * PAGE_SIZE;
dprintk("attempting mmap of %lu bytes\n", info->mmap_size);
down_write(&ctx->mm->mmap_sem);
info->mmap_base = do_mmap(NULL, 0, info->mmap_size,
- PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
+ PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE,
0);
if (IS_ERR((void *)info->mmap_base)) {
up_write(&ctx->mm->mmap_sem);
- printk("mmap err: %ld\n", -info->mmap_base);
info->mmap_size = 0;
aio_free_ring(ctx);
return -EAGAIN;
kunmap_atomic((void *)((unsigned long)__event & PAGE_MASK), km); \
} while(0)
+static void ctx_rcu_free(struct rcu_head *head)
+{
+ struct kioctx *ctx = container_of(head, struct kioctx, rcu_head);
+ unsigned nr_events = ctx->max_reqs;
+
+ kmem_cache_free(kioctx_cachep, ctx);
+
+ if (nr_events) {
+ spin_lock(&aio_nr_lock);
+ BUG_ON(aio_nr - nr_events > aio_nr);
+ aio_nr -= nr_events;
+ spin_unlock(&aio_nr_lock);
+ }
+}
+
+/* __put_ioctx
+ * Called when the last user of an aio context has gone away,
+ * and the struct needs to be freed.
+ */
+static void __put_ioctx(struct kioctx *ctx)
+{
+ BUG_ON(ctx->reqs_active);
+
+ cancel_delayed_work(&ctx->wq);
+ cancel_work_sync(&ctx->wq.work);
+ aio_free_ring(ctx);
+ mmdrop(ctx->mm);
+ ctx->mm = NULL;
+ pr_debug("__put_ioctx: freeing %p\n", ctx);
+ call_rcu(&ctx->rcu_head, ctx_rcu_free);
+}
+
+static inline void get_ioctx(struct kioctx *kioctx)
+{
+ BUG_ON(atomic_read(&kioctx->users) <= 0);
+ atomic_inc(&kioctx->users);
+}
+
+static inline int try_get_ioctx(struct kioctx *kioctx)
+{
+ return atomic_inc_not_zero(&kioctx->users);
+}
+
+static inline void put_ioctx(struct kioctx *kioctx)
+{
+ BUG_ON(atomic_read(&kioctx->users) <= 0);
+ if (unlikely(atomic_dec_and_test(&kioctx->users)))
+ __put_ioctx(kioctx);
+}
+
/* ioctx_alloc
* Allocates and initializes an ioctx. Returns an ERR_PTR if it failed.
*/
{
struct mm_struct *mm;
struct kioctx *ctx;
+ int did_sync = 0;
/* Prevent overflows */
if ((nr_events > (0x10000000U / sizeof(struct io_event))) ||
return ERR_PTR(-EINVAL);
}
- if (nr_events > aio_max_nr)
+ if ((unsigned long)nr_events > aio_max_nr)
return ERR_PTR(-EAGAIN);
- ctx = kmem_cache_alloc(kioctx_cachep, GFP_KERNEL);
+ ctx = kmem_cache_zalloc(kioctx_cachep, GFP_KERNEL);
if (!ctx)
return ERR_PTR(-ENOMEM);
- memset(ctx, 0, sizeof(*ctx));
ctx->max_reqs = nr_events;
mm = ctx->mm = current->mm;
atomic_inc(&mm->mm_count);
INIT_LIST_HEAD(&ctx->active_reqs);
INIT_LIST_HEAD(&ctx->run_list);
- INIT_WORK(&ctx->wq, aio_kick_handler, ctx);
+ INIT_DELAYED_WORK(&ctx->wq, aio_kick_handler);
if (aio_setup_ring(ctx) < 0)
goto out_freectx;
/* limit the number of system wide aios */
- atomic_add(ctx->max_reqs, &aio_nr); /* undone by __put_ioctx */
- if (unlikely(atomic_read(&aio_nr) > aio_max_nr))
+ do {
+ spin_lock_bh(&aio_nr_lock);
+ if (aio_nr + nr_events > aio_max_nr ||
+ aio_nr + nr_events < aio_nr)
+ ctx->max_reqs = 0;
+ else
+ aio_nr += ctx->max_reqs;
+ spin_unlock_bh(&aio_nr_lock);
+ if (ctx->max_reqs || did_sync)
+ break;
+
+ /* wait for rcu callbacks to have completed before giving up */
+ synchronize_rcu();
+ did_sync = 1;
+ ctx->max_reqs = nr_events;
+ } while (1);
+
+ if (ctx->max_reqs == 0)
goto out_cleanup;
- /* now link into global list. kludge. FIXME */
- write_lock(&mm->ioctx_list_lock);
- ctx->next = mm->ioctx_list;
- mm->ioctx_list = ctx;
- write_unlock(&mm->ioctx_list_lock);
+ /* now link into global list. */
+ spin_lock(&mm->ioctx_lock);
+ hlist_add_head_rcu(&ctx->list, &mm->ioctx_list);
+ spin_unlock(&mm->ioctx_lock);
dprintk("aio: allocated ioctx %p[%ld]: mm=%p mask=0x%x\n",
ctx, ctx->user_id, current->mm, ctx->ring_info.nr);
return ctx;
out_cleanup:
- atomic_sub(ctx->max_reqs, &aio_nr);
- ctx->max_reqs = 0; /* prevent __put_ioctx from sub'ing aio_nr */
__put_ioctx(ctx);
return ERR_PTR(-EAGAIN);
struct task_struct *tsk = current;
DECLARE_WAITQUEUE(wait, tsk);
+ spin_lock_irq(&ctx->ctx_lock);
if (!ctx->reqs_active)
- return;
+ goto out;
add_wait_queue(&ctx->wait, &wait);
set_task_state(tsk, TASK_UNINTERRUPTIBLE);
while (ctx->reqs_active) {
- schedule();
+ spin_unlock_irq(&ctx->ctx_lock);
+ io_schedule();
set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+ spin_lock_irq(&ctx->ctx_lock);
}
__set_task_state(tsk, TASK_RUNNING);
remove_wait_queue(&ctx->wait, &wait);
+
+out:
+ spin_unlock_irq(&ctx->ctx_lock);
}
/* wait_on_sync_kiocb:
* Waits on the given sync kiocb to complete.
*/
-ssize_t fastcall wait_on_sync_kiocb(struct kiocb *iocb)
+ssize_t wait_on_sync_kiocb(struct kiocb *iocb)
{
while (iocb->ki_users) {
set_current_state(TASK_UNINTERRUPTIBLE);
if (!iocb->ki_users)
break;
- schedule();
+ io_schedule();
}
__set_current_state(TASK_RUNNING);
return iocb->ki_user_data;
}
+EXPORT_SYMBOL(wait_on_sync_kiocb);
/* exit_aio: called when the last user of mm goes away. At this point,
* there is no way for any new requests to be submited or any of the
* go away, they will call put_ioctx and release any pinned memory
* associated with the request (held via struct page * references).
*/
-void fastcall exit_aio(struct mm_struct *mm)
+void exit_aio(struct mm_struct *mm)
{
- struct kioctx *ctx = mm->ioctx_list;
- mm->ioctx_list = NULL;
- while (ctx) {
- struct kioctx *next = ctx->next;
- ctx->next = NULL;
+ struct kioctx *ctx;
+
+ while (!hlist_empty(&mm->ioctx_list)) {
+ ctx = hlist_entry(mm->ioctx_list.first, struct kioctx, list);
+ hlist_del_rcu(&ctx->list);
+
aio_cancel_all(ctx);
wait_for_all_aios(ctx);
/*
- * this is an overkill, but ensures we don't leave
- * the ctx on the aio_wq
+ * Ensure we don't leave the ctx on the aio_wq
*/
- flush_workqueue(aio_wq);
+ cancel_work_sync(&ctx->wq.work);
if (1 != atomic_read(&ctx->users))
printk(KERN_DEBUG
atomic_read(&ctx->users), ctx->dead,
ctx->reqs_active);
put_ioctx(ctx);
- ctx = next;
}
}
-/* __put_ioctx
- * Called when the last user of an aio context has gone away,
- * and the struct needs to be freed.
- */
-void fastcall __put_ioctx(struct kioctx *ctx)
-{
- unsigned nr_events = ctx->max_reqs;
-
- if (unlikely(ctx->reqs_active))
- BUG();
-
- cancel_delayed_work(&ctx->wq);
- flush_workqueue(aio_wq);
- aio_free_ring(ctx);
- mmdrop(ctx->mm);
- ctx->mm = NULL;
- pr_debug("__put_ioctx: freeing %p\n", ctx);
- kmem_cache_free(kioctx_cachep, ctx);
-
- atomic_sub(nr_events, &aio_nr);
-}
-
/* aio_get_req
* Allocate a slot for an aio request. Increments the users count
* of the kioctx so that the kioctx stays around until all requests are
* This prevents races between the aio code path referencing the
* req (after submitting it) and aio_complete() freeing the req.
*/
-static struct kiocb *FASTCALL(__aio_get_req(struct kioctx *ctx));
-static struct kiocb fastcall *__aio_get_req(struct kioctx *ctx)
+static struct kiocb *__aio_get_req(struct kioctx *ctx)
{
struct kiocb *req = NULL;
struct aio_ring *ring;
if (unlikely(!req))
return NULL;
- req->ki_flags = 1 << KIF_LOCKED;
+ req->ki_flags = 0;
req->ki_users = 2;
req->ki_key = 0;
req->ki_ctx = ctx;
req->ki_retry = NULL;
req->ki_dtor = NULL;
req->private = NULL;
+ req->ki_iovec = NULL;
INIT_LIST_HEAD(&req->ki_run_list);
+ req->ki_eventfd = NULL;
/* Check if the completion queue has enough free space to
* accept an event from this io.
ring = kmap_atomic(ctx->ring_info.ring_pages[0], KM_USER0);
if (ctx->reqs_active < aio_ring_avail(&ctx->ring_info, ring)) {
list_add(&req->ki_list, &ctx->active_reqs);
- get_ioctx(ctx);
ctx->reqs_active++;
okay = 1;
}
static inline void really_put_req(struct kioctx *ctx, struct kiocb *req)
{
+ assert_spin_locked(&ctx->ctx_lock);
+
+ if (req->ki_eventfd != NULL)
+ eventfd_ctx_put(req->ki_eventfd);
if (req->ki_dtor)
req->ki_dtor(req);
+ if (req->ki_iovec != &req->ki_inline_vec)
+ kfree(req->ki_iovec);
kmem_cache_free(kiocb_cachep, req);
ctx->reqs_active--;
if (unlikely(!ctx->reqs_active && ctx->dead))
- wake_up(&ctx->wait);
+ wake_up_all(&ctx->wait);
}
-static void aio_fput_routine(void *data)
+static void aio_fput_routine(struct work_struct *data)
{
spin_lock_irq(&fput_lock);
while (likely(!list_empty(&fput_head))) {
list_del(&req->ki_list);
spin_unlock_irq(&fput_lock);
- /* Complete the fput */
- __fput(req->ki_filp);
+ /* Complete the fput(s) */
+ if (req->ki_filp != NULL)
+ fput(req->ki_filp);
/* Link the iocb into the context's free list */
spin_lock_irq(&ctx->ctx_lock);
*/
static int __aio_put_req(struct kioctx *ctx, struct kiocb *req)
{
- dprintk(KERN_DEBUG "aio_put(%p): f_count=%d\n",
- req, atomic_read(&req->ki_filp->f_count));
+ dprintk(KERN_DEBUG "aio_put(%p): f_count=%ld\n",
+ req, atomic_long_read(&req->ki_filp->f_count));
+
+ assert_spin_locked(&ctx->ctx_lock);
- req->ki_users --;
- if (unlikely(req->ki_users < 0))
- BUG();
+ req->ki_users--;
+ BUG_ON(req->ki_users < 0);
if (likely(req->ki_users))
return 0;
list_del(&req->ki_list); /* remove from active_reqs */
req->ki_cancel = NULL;
req->ki_retry = NULL;
- /* Must be done under the lock to serialise against cancellation.
- * Call this aio_fput as it duplicates fput via the fput_work.
+ /*
+ * Try to optimize the aio and eventfd file* puts, by avoiding to
+ * schedule work in case it is not final fput() time. In normal cases,
+ * we would not be holding the last reference to the file*, so
+ * this function will be executed w/out any aio kthread wakeup.
*/
- if (unlikely(atomic_dec_and_test(&req->ki_filp->f_count))) {
+ if (unlikely(!fput_atomic(req->ki_filp))) {
get_ioctx(ctx);
spin_lock(&fput_lock);
list_add(&req->ki_list, &fput_head);
spin_unlock(&fput_lock);
- queue_work(aio_wq, &fput_work);
- } else
+ schedule_work(&fput_work);
+ } else {
+ req->ki_filp = NULL;
really_put_req(ctx, req);
+ }
return 1;
}
* Returns true if this put was the last user of the kiocb,
* false if the request is still in use.
*/
-int fastcall aio_put_req(struct kiocb *req)
+int aio_put_req(struct kiocb *req)
{
struct kioctx *ctx = req->ki_ctx;
int ret;
spin_lock_irq(&ctx->ctx_lock);
ret = __aio_put_req(ctx, req);
spin_unlock_irq(&ctx->ctx_lock);
- if (ret)
- put_ioctx(ctx);
return ret;
}
+EXPORT_SYMBOL(aio_put_req);
-/* Lookup an ioctx id. ioctx_list is lockless for reads.
- * FIXME: this is O(n) and is only suitable for development.
- */
-struct kioctx *lookup_ioctx(unsigned long ctx_id)
+static struct kioctx *lookup_ioctx(unsigned long ctx_id)
{
- struct kioctx *ioctx;
- struct mm_struct *mm;
+ struct mm_struct *mm = current->mm;
+ struct kioctx *ctx, *ret = NULL;
+ struct hlist_node *n;
+
+ rcu_read_lock();
- mm = current->mm;
- read_lock(&mm->ioctx_list_lock);
- for (ioctx = mm->ioctx_list; ioctx; ioctx = ioctx->next)
- if (likely(ioctx->user_id == ctx_id && !ioctx->dead)) {
- get_ioctx(ioctx);
+ hlist_for_each_entry_rcu(ctx, n, &mm->ioctx_list, list) {
+ /*
+ * RCU protects us against accessing freed memory but
+ * we have to be careful not to get a reference when the
+ * reference count already dropped to 0 (ctx->dead test
+ * is unreliable because of races).
+ */
+ if (ctx->user_id == ctx_id && !ctx->dead && try_get_ioctx(ctx)){
+ ret = ctx;
break;
}
- read_unlock(&mm->ioctx_list_lock);
-
- return ioctx;
-}
-
-/*
- * use_mm
- * Makes the calling kernel thread take on the specified
- * mm context.
- * Called by the retry thread execute retries within the
- * iocb issuer's mm context, so that copy_from/to_user
- * operations work seamlessly for aio.
- * (Note: this routine is intended to be called only
- * from a kernel thread context)
- */
-static void use_mm(struct mm_struct *mm)
-{
- struct mm_struct *active_mm;
- struct task_struct *tsk = current;
-
- task_lock(tsk);
- tsk->flags |= PF_BORROWED_MM;
- active_mm = tsk->active_mm;
- atomic_inc(&mm->mm_count);
- tsk->mm = mm;
- tsk->active_mm = mm;
- /*
- * Note that on UML this *requires* PF_BORROWED_MM to be set, otherwise
- * it won't work. Update it accordingly if you change it here
- */
- activate_mm(active_mm, mm);
- task_unlock(tsk);
-
- mmdrop(active_mm);
-}
-
-/*
- * unuse_mm
- * Reverses the effect of use_mm, i.e. releases the
- * specified mm context which was earlier taken on
- * by the calling kernel thread
- * (Note: this routine is intended to be called only
- * from a kernel thread context)
- *
- * Comments: Called with ctx->ctx_lock held. This nests
- * task_lock instead ctx_lock.
- */
-static void unuse_mm(struct mm_struct *mm)
-{
- struct task_struct *tsk = current;
+ }
- task_lock(tsk);
- tsk->flags &= ~PF_BORROWED_MM;
- tsk->mm = NULL;
- /* active_mm is still 'mm' */
- enter_lazy_tlb(mm, tsk);
- task_unlock(tsk);
+ rcu_read_unlock();
+ return ret;
}
/*
* the kiocb (to tell the caller to activate the work
* queue to process it), or 0, if it found that it was
* already queued.
- *
- * Should be called with the spin lock iocb->ki_ctx->ctx_lock
- * held
*/
static inline int __queue_kicked_iocb(struct kiocb *iocb)
{
struct kioctx *ctx = iocb->ki_ctx;
+ assert_spin_locked(&ctx->ctx_lock);
+
if (list_empty(&iocb->ki_run_list)) {
list_add_tail(&iocb->ki_run_list,
&ctx->run_list);
* invoked both for initial i/o submission and
* subsequent retries via the aio_kick_handler.
* Expects to be invoked with iocb->ki_ctx->lock
- * already held. The lock is released and reaquired
+ * already held. The lock is released and reacquired
* as needed during processing.
*
* Calls the iocb retry method (already setup for the
ssize_t (*retry)(struct kiocb *);
ssize_t ret;
- if (iocb->ki_retried++ > 1024*1024) {
- printk("Maximal retry count. Bytes done %Zd\n",
- iocb->ki_nbytes - iocb->ki_left);
- return -EAGAIN;
- }
-
- if (!(iocb->ki_retried & 0xff)) {
- pr_debug("%ld retry: %d of %d\n", iocb->ki_retried,
- iocb->ki_nbytes - iocb->ki_left, iocb->ki_nbytes);
- }
-
if (!(retry = iocb->ki_retry)) {
printk("aio_run_iocb: iocb->ki_retry = NULL\n");
return 0;
/*
* Now we are all set to call the retry method in async
- * context. By setting this thread's io_wait context
- * to point to the wait queue entry inside the currently
- * running iocb for the duration of the retry, we ensure
- * that async notification wakeups are queued by the
- * operation instead of blocking waits, and when notified,
- * cause the iocb to be kicked for continuation (through
- * the aio_wake_function callback).
+ * context.
*/
- BUG_ON(current->io_wait != NULL);
- current->io_wait = &iocb->ki_wait;
ret = retry(iocb);
- current->io_wait = NULL;
- if (-EIOCBRETRY != ret) {
- if (-EIOCBQUEUED != ret) {
- BUG_ON(!list_empty(&iocb->ki_wait.task_list));
- aio_complete(iocb, ret, 0);
- /* must not access the iocb after this */
- }
- } else {
+ if (ret != -EIOCBRETRY && ret != -EIOCBQUEUED) {
/*
- * Issue an additional retry to avoid waiting forever if
- * no waits were queued (e.g. in case of a short read).
+ * There's no easy way to restart the syscall since other AIO's
+ * may be already running. Just fail this IO with EINTR.
*/
- if (list_empty(&iocb->ki_wait.task_list))
- kiocbSetKicked(iocb);
+ if (unlikely(ret == -ERESTARTSYS || ret == -ERESTARTNOINTR ||
+ ret == -ERESTARTNOHAND || ret == -ERESTART_RESTARTBLOCK))
+ ret = -EINTR;
+ aio_complete(iocb, ret, 0);
}
out:
spin_lock_irq(&ctx->ctx_lock);
* Process all pending retries queued on the ioctx
* run list.
* Assumes it is operating within the aio issuer's mm
- * context. Expects to be called with ctx->ctx_lock held
+ * context.
*/
static int __aio_run_iocbs(struct kioctx *ctx)
{
struct kiocb *iocb;
- LIST_HEAD(run_list);
+ struct list_head run_list;
- list_splice_init(&ctx->run_list, &run_list);
+ assert_spin_locked(&ctx->ctx_lock);
+
+ list_replace_init(&ctx->run_list, &run_list);
while (!list_empty(&run_list)) {
iocb = list_entry(run_list.next, struct kiocb,
ki_run_list);
*/
iocb->ki_users++; /* grab extra reference */
aio_run_iocb(iocb);
- if (__aio_put_req(ctx, iocb)) /* drop extra ref */
- put_ioctx(ctx);
+ __aio_put_req(ctx, iocb);
}
if (!list_empty(&ctx->run_list))
return 1;
queue_delayed_work(aio_wq, &ctx->wq, timeout);
}
-
-/*
- * aio_run_iocbs:
- * Process all pending retries queued on the ioctx
- * run list.
- * Assumes it is operating within the aio issuer's mm
- * context.
- */
-static inline void aio_run_iocbs(struct kioctx *ctx)
-{
- int requeue;
-
- spin_lock_irq(&ctx->ctx_lock);
-
- requeue = __aio_run_iocbs(ctx);
- spin_unlock_irq(&ctx->ctx_lock);
- if (requeue)
- aio_queue_work(ctx);
-}
-
/*
- * just like aio_run_iocbs, but keeps running them until
- * the list stays empty
+ * aio_run_all_iocbs:
+ * Process all pending retries queued on the ioctx
+ * run list, and keep running them until the list
+ * stays empty.
+ * Assumes it is operating within the aio issuer's mm context.
*/
static inline void aio_run_all_iocbs(struct kioctx *ctx)
{
* space.
* Run on aiod's context.
*/
-static void aio_kick_handler(void *data)
+static void aio_kick_handler(struct work_struct *work)
{
- struct kioctx *ctx = data;
+ struct kioctx *ctx = container_of(work, struct kioctx, wq.work);
mm_segment_t oldfs = get_fs();
+ struct mm_struct *mm;
int requeue;
set_fs(USER_DS);
use_mm(ctx->mm);
spin_lock_irq(&ctx->ctx_lock);
requeue =__aio_run_iocbs(ctx);
- unuse_mm(ctx->mm);
+ mm = ctx->mm;
spin_unlock_irq(&ctx->ctx_lock);
+ unuse_mm(mm);
set_fs(oldfs);
/*
* we're in a worker thread already, don't use queue_delayed_work,
*/
if (requeue)
- queue_work(aio_wq, &ctx->wq);
+ queue_delayed_work(aio_wq, &ctx->wq, 0);
}
* and if required activate the aio work queue to process
* it
*/
-static void queue_kicked_iocb(struct kiocb *iocb)
+static void try_queue_kicked_iocb(struct kiocb *iocb)
{
struct kioctx *ctx = iocb->ki_ctx;
unsigned long flags;
int run = 0;
- WARN_ON((!list_empty(&iocb->ki_wait.task_list)));
-
spin_lock_irqsave(&ctx->ctx_lock, flags);
- run = __queue_kicked_iocb(iocb);
+ /* set this inside the lock so that we can't race with aio_run_iocb()
+ * testing it and putting the iocb on the run list under the lock */
+ if (!kiocbTryKick(iocb))
+ run = __queue_kicked_iocb(iocb);
spin_unlock_irqrestore(&ctx->ctx_lock, flags);
if (run)
aio_queue_work(ctx);
/*
* kick_iocb:
* Called typically from a wait queue callback context
- * (aio_wake_function) to trigger a retry of the iocb.
+ * to trigger a retry of the iocb.
* The retry is usually executed by aio workqueue
* threads (See aio_kick_handler).
*/
-void fastcall kick_iocb(struct kiocb *iocb)
+void kick_iocb(struct kiocb *iocb)
{
/* sync iocbs are easy: they can only ever be executing from a
* single context. */
return;
}
- /* If its already kicked we shouldn't queue it again */
- if (!kiocbTryKick(iocb)) {
- queue_kicked_iocb(iocb);
- }
+ try_queue_kicked_iocb(iocb);
}
EXPORT_SYMBOL(kick_iocb);
* Returns true if this is the last user of the request. The
* only other user of the request can be the cancellation code.
*/
-int fastcall aio_complete(struct kiocb *iocb, long res, long res2)
+int aio_complete(struct kiocb *iocb, long res, long res2)
{
struct kioctx *ctx = iocb->ki_ctx;
struct aio_ring_info *info;
unsigned long tail;
int ret;
- /* Special case handling for sync iocbs: events go directly
- * into the iocb for fast handling. Note that this will not
- * work if we allow sync kiocbs to be cancelled. in which
- * case the usage count checks will have to move under ctx_lock
- * for all cases.
+ /*
+ * Special case handling for sync iocbs:
+ * - events go directly into the iocb for fast handling
+ * - the sync task with the iocb in its stack holds the single iocb
+ * ref, no other paths have a way to get another ref
+ * - the sync task helpfully left a reference to itself in the iocb
*/
if (is_sync_kiocb(iocb)) {
- int ret;
-
+ BUG_ON(iocb->ki_users != 1);
iocb->ki_user_data = res;
- if (iocb->ki_users == 1) {
- iocb->ki_users = 0;
- ret = 1;
- } else {
- spin_lock_irq(&ctx->ctx_lock);
- iocb->ki_users--;
- ret = (0 == iocb->ki_users);
- spin_unlock_irq(&ctx->ctx_lock);
- }
- /* sync iocbs put the task here for us */
+ iocb->ki_users = 0;
wake_up_process(iocb->ki_obj.tsk);
- return ret;
+ return 1;
}
info = &ctx->ring_info;
pr_debug("added to ring %p at [%lu]\n", iocb, tail);
- pr_debug("%ld retries: %d of %d\n", iocb->ki_retried,
- iocb->ki_nbytes - iocb->ki_left, iocb->ki_nbytes);
+ /*
+ * Check if the user asked us to deliver the result through an
+ * eventfd. The eventfd_signal() function is safe to be called
+ * from IRQ context.
+ */
+ if (iocb->ki_eventfd != NULL)
+ eventfd_signal(iocb->ki_eventfd, 1);
+
put_rq:
/* everything turned out well, dispose of the aiocb. */
ret = __aio_put_req(ctx, iocb);
- spin_unlock_irqrestore(&ctx->ctx_lock, flags);
+ /*
+ * We have to order our ring_info tail store above and test
+ * of the wait list below outside the wait lock. This is
+ * like in wake_up_bit() where clearing a bit has to be
+ * ordered with the unlocked test.
+ */
+ smp_mb();
if (waitqueue_active(&ctx->wait))
wake_up(&ctx->wait);
- if (ret)
- put_ioctx(ctx);
-
+ spin_unlock_irqrestore(&ctx->ctx_lock, flags);
return ret;
}
+EXPORT_SYMBOL(aio_complete);
/* aio_read_evt
* Pull an event off of the ioctx's event ring. Returns the number of
static inline void init_timeout(struct aio_timeout *to)
{
- init_timer(&to->timer);
- to->timer.data = (unsigned long)to;
- to->timer.function = timeout_func;
+ setup_timer_on_stack(&to->timer, timeout_func, (unsigned long) to);
to->timed_out = 0;
to->p = current;
}
break;
if (min_nr <= i)
break;
- ret = 0;
+ if (unlikely(ctx->dead)) {
+ ret = -EINVAL;
+ break;
+ }
if (to.timed_out) /* Only check after read evt */
break;
- schedule();
+ /* Try to only show up in io wait if there are ops
+ * in flight */
+ if (ctx->reqs_active)
+ io_schedule();
+ else
+ schedule();
if (signal_pending(tsk)) {
ret = -EINTR;
break;
if (timeout)
clear_timeout(&to);
out:
+ destroy_timer_on_stack(&to.timer);
return i ? i : ret;
}
static void io_destroy(struct kioctx *ioctx)
{
struct mm_struct *mm = current->mm;
- struct kioctx **tmp;
int was_dead;
/* delete the entry from the list is someone else hasn't already */
- write_lock(&mm->ioctx_list_lock);
+ spin_lock(&mm->ioctx_lock);
was_dead = ioctx->dead;
ioctx->dead = 1;
- for (tmp = &mm->ioctx_list; *tmp && *tmp != ioctx;
- tmp = &(*tmp)->next)
- ;
- if (*tmp)
- *tmp = ioctx->next;
- write_unlock(&mm->ioctx_list_lock);
+ hlist_del_rcu(&ioctx->list);
+ spin_unlock(&mm->ioctx_lock);
dprintk("aio_release(%p)\n", ioctx);
if (likely(!was_dead))
aio_cancel_all(ioctx);
wait_for_all_aios(ioctx);
+
+ /*
+ * Wake up any waiters. The setting of ctx->dead must be seen
+ * by other CPUs at this point. Right now, we rely on the
+ * locking done by the above calls to ensure this consistency.
+ */
+ wake_up_all(&ioctx->wait);
put_ioctx(ioctx); /* once for the lookup */
}
* pointer is passed for ctxp. Will fail with -ENOSYS if not
* implemented.
*/
-asmlinkage long sys_io_setup(unsigned nr_events, aio_context_t __user *ctxp)
+SYSCALL_DEFINE2(io_setup, unsigned, nr_events, aio_context_t __user *, ctxp)
{
struct kioctx *ioctx = NULL;
unsigned long ctx;
goto out;
ret = -EINVAL;
- if (unlikely(ctx || (int)nr_events <= 0)) {
- pr_debug("EINVAL: io_setup: ctx or nr_events > max\n");
+ if (unlikely(ctx || nr_events == 0)) {
+ pr_debug("EINVAL: io_setup: ctx %lu nr_events %u\n",
+ ctx, nr_events);
goto out;
}
/* sys_io_destroy:
* Destroy the aio_context specified. May cancel any outstanding
* AIOs and block on completion. Will fail with -ENOSYS if not
- * implemented. May fail with -EFAULT if the context pointed to
+ * implemented. May fail with -EINVAL if the context pointed to
* is invalid.
*/
-asmlinkage long sys_io_destroy(aio_context_t ctx)
+SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx)
{
struct kioctx *ioctx = lookup_ioctx(ctx);
if (likely(NULL != ioctx)) {
return -EINVAL;
}
-/*
- * Default retry method for aio_read (also used for first time submit)
- * Responsible for updating iocb state as retries progress
- */
-static ssize_t aio_pread(struct kiocb *iocb)
+static void aio_advance_iovec(struct kiocb *iocb, ssize_t ret)
{
- struct file *file = iocb->ki_filp;
- struct address_space *mapping = file->f_mapping;
- struct inode *inode = mapping->host;
- ssize_t ret = 0;
-
- ret = file->f_op->aio_read(iocb, iocb->ki_buf,
- iocb->ki_left, iocb->ki_pos);
-
- /*
- * Can't just depend on iocb->ki_left to determine
- * whether we are done. This may have been a short read.
- */
- if (ret > 0) {
- iocb->ki_buf += ret;
- iocb->ki_left -= ret;
- /*
- * For pipes and sockets we return once we have
- * some data; for regular files we retry till we
- * complete the entire read or find that we can't
- * read any more data (e.g short reads).
- */
- if (!S_ISFIFO(inode->i_mode) && !S_ISSOCK(inode->i_mode))
- ret = -EIOCBRETRY;
+ struct iovec *iov = &iocb->ki_iovec[iocb->ki_cur_seg];
+
+ BUG_ON(ret <= 0);
+
+ while (iocb->ki_cur_seg < iocb->ki_nr_segs && ret > 0) {
+ ssize_t this = min((ssize_t)iov->iov_len, ret);
+ iov->iov_base += this;
+ iov->iov_len -= this;
+ iocb->ki_left -= this;
+ ret -= this;
+ if (iov->iov_len == 0) {
+ iocb->ki_cur_seg++;
+ iov++;
+ }
}
- /* This means we must have transferred all that we could */
- /* No need to retry anymore */
- if ((ret == 0) || (iocb->ki_left == 0))
- ret = iocb->ki_nbytes - iocb->ki_left;
-
- return ret;
+ /* the caller should not have done more io than what fit in
+ * the remaining iovecs */
+ BUG_ON(ret > 0 && iocb->ki_left == 0);
}
-/*
- * Default retry method for aio_write (also used for first time submit)
- * Responsible for updating iocb state as retries progress
- */
-static ssize_t aio_pwrite(struct kiocb *iocb)
+static ssize_t aio_rw_vect_retry(struct kiocb *iocb)
{
struct file *file = iocb->ki_filp;
+ struct address_space *mapping = file->f_mapping;
+ struct inode *inode = mapping->host;
+ ssize_t (*rw_op)(struct kiocb *, const struct iovec *,
+ unsigned long, loff_t);
ssize_t ret = 0;
+ unsigned short opcode;
- ret = file->f_op->aio_write(iocb, iocb->ki_buf,
- iocb->ki_left, iocb->ki_pos);
+ if ((iocb->ki_opcode == IOCB_CMD_PREADV) ||
+ (iocb->ki_opcode == IOCB_CMD_PREAD)) {
+ rw_op = file->f_op->aio_read;
+ opcode = IOCB_CMD_PREADV;
+ } else {
+ rw_op = file->f_op->aio_write;
+ opcode = IOCB_CMD_PWRITEV;
+ }
- if (ret > 0) {
- iocb->ki_buf += ret;
- iocb->ki_left -= ret;
+ /* This matches the pread()/pwrite() logic */
+ if (iocb->ki_pos < 0)
+ return -EINVAL;
- ret = -EIOCBRETRY;
- }
+ do {
+ ret = rw_op(iocb, &iocb->ki_iovec[iocb->ki_cur_seg],
+ iocb->ki_nr_segs - iocb->ki_cur_seg,
+ iocb->ki_pos);
+ if (ret > 0)
+ aio_advance_iovec(iocb, ret);
+
+ /* retry all partial writes. retry partial reads as long as its a
+ * regular file. */
+ } while (ret > 0 && iocb->ki_left > 0 &&
+ (opcode == IOCB_CMD_PWRITEV ||
+ (!S_ISFIFO(inode->i_mode) && !S_ISSOCK(inode->i_mode))));
/* This means we must have transferred all that we could */
/* No need to retry anymore */
if ((ret == 0) || (iocb->ki_left == 0))
ret = iocb->ki_nbytes - iocb->ki_left;
+ /* If we managed to write some out we return that, rather than
+ * the eventual error. */
+ if (opcode == IOCB_CMD_PWRITEV
+ && ret < 0 && ret != -EIOCBQUEUED && ret != -EIOCBRETRY
+ && iocb->ki_nbytes - iocb->ki_left)
+ ret = iocb->ki_nbytes - iocb->ki_left;
+
return ret;
}
return ret;
}
+static ssize_t aio_setup_vectored_rw(int type, struct kiocb *kiocb, bool compat)
+{
+ ssize_t ret;
+
+#ifdef CONFIG_COMPAT
+ if (compat)
+ ret = compat_rw_copy_check_uvector(type,
+ (struct compat_iovec __user *)kiocb->ki_buf,
+ kiocb->ki_nbytes, 1, &kiocb->ki_inline_vec,
+ &kiocb->ki_iovec);
+ else
+#endif
+ ret = rw_copy_check_uvector(type,
+ (struct iovec __user *)kiocb->ki_buf,
+ kiocb->ki_nbytes, 1, &kiocb->ki_inline_vec,
+ &kiocb->ki_iovec);
+ if (ret < 0)
+ goto out;
+
+ kiocb->ki_nr_segs = kiocb->ki_nbytes;
+ kiocb->ki_cur_seg = 0;
+ /* ki_nbytes/left now reflect bytes instead of segs */
+ kiocb->ki_nbytes = ret;
+ kiocb->ki_left = ret;
+
+ ret = 0;
+out:
+ return ret;
+}
+
+static ssize_t aio_setup_single_vector(struct kiocb *kiocb)
+{
+ kiocb->ki_iovec = &kiocb->ki_inline_vec;
+ kiocb->ki_iovec->iov_base = kiocb->ki_buf;
+ kiocb->ki_iovec->iov_len = kiocb->ki_left;
+ kiocb->ki_nr_segs = 1;
+ kiocb->ki_cur_seg = 0;
+ return 0;
+}
+
/*
* aio_setup_iocb:
* Performs the initial checks and aio retry method
* setup for the kiocb at the time of io submission.
*/
-static ssize_t aio_setup_iocb(struct kiocb *kiocb)
+static ssize_t aio_setup_iocb(struct kiocb *kiocb, bool compat)
{
struct file *file = kiocb->ki_filp;
ssize_t ret = 0;
if (unlikely(!access_ok(VERIFY_WRITE, kiocb->ki_buf,
kiocb->ki_left)))
break;
+ ret = security_file_permission(file, MAY_READ);
+ if (unlikely(ret))
+ break;
+ ret = aio_setup_single_vector(kiocb);
+ if (ret)
+ break;
ret = -EINVAL;
if (file->f_op->aio_read)
- kiocb->ki_retry = aio_pread;
+ kiocb->ki_retry = aio_rw_vect_retry;
break;
case IOCB_CMD_PWRITE:
ret = -EBADF;
if (unlikely(!access_ok(VERIFY_READ, kiocb->ki_buf,
kiocb->ki_left)))
break;
+ ret = security_file_permission(file, MAY_WRITE);
+ if (unlikely(ret))
+ break;
+ ret = aio_setup_single_vector(kiocb);
+ if (ret)
+ break;
ret = -EINVAL;
if (file->f_op->aio_write)
- kiocb->ki_retry = aio_pwrite;
+ kiocb->ki_retry = aio_rw_vect_retry;
+ break;
+ case IOCB_CMD_PREADV:
+ ret = -EBADF;
+ if (unlikely(!(file->f_mode & FMODE_READ)))
+ break;
+ ret = security_file_permission(file, MAY_READ);
+ if (unlikely(ret))
+ break;
+ ret = aio_setup_vectored_rw(READ, kiocb, compat);
+ if (ret)
+ break;
+ ret = -EINVAL;
+ if (file->f_op->aio_read)
+ kiocb->ki_retry = aio_rw_vect_retry;
+ break;
+ case IOCB_CMD_PWRITEV:
+ ret = -EBADF;
+ if (unlikely(!(file->f_mode & FMODE_WRITE)))
+ break;
+ ret = security_file_permission(file, MAY_WRITE);
+ if (unlikely(ret))
+ break;
+ ret = aio_setup_vectored_rw(WRITE, kiocb, compat);
+ if (ret)
+ break;
+ ret = -EINVAL;
+ if (file->f_op->aio_write)
+ kiocb->ki_retry = aio_rw_vect_retry;
break;
case IOCB_CMD_FDSYNC:
ret = -EINVAL;
return 0;
}
-/*
- * aio_wake_function:
- * wait queue callback function for aio notification,
- * Simply triggers a retry of the operation via kick_iocb.
- *
- * This callback is specified in the wait queue entry in
- * a kiocb (current->io_wait points to this wait queue
- * entry when an aio operation executes; it is used
- * instead of a synchronous wait when an i/o blocking
- * condition is encountered during aio).
- *
- * Note:
- * This routine is executed with the wait queue lock held.
- * Since kick_iocb acquires iocb->ctx->ctx_lock, it nests
- * the ioctx lock inside the wait queue lock. This is safe
- * because this callback isn't used for wait queues which
- * are nested inside ioctx lock (i.e. ctx->wait)
- */
-static int aio_wake_function(wait_queue_t *wait, unsigned mode,
- int sync, void *key)
-{
- struct kiocb *iocb = container_of(wait, struct kiocb, ki_wait);
-
- list_del_init(&wait->task_list);
- kick_iocb(iocb);
- return 1;
-}
-
-int fastcall io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
- struct iocb *iocb)
+static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
+ struct iocb *iocb, bool compat)
{
struct kiocb *req;
struct file *file;
ssize_t ret;
/* enforce forwards compatibility on users */
- if (unlikely(iocb->aio_reserved1 || iocb->aio_reserved2 ||
- iocb->aio_reserved3)) {
+ if (unlikely(iocb->aio_reserved1 || iocb->aio_reserved2)) {
pr_debug("EINVAL: io_submit: reserve field set\n");
return -EINVAL;
}
fput(file);
return -EAGAIN;
}
-
req->ki_filp = file;
+ if (iocb->aio_flags & IOCB_FLAG_RESFD) {
+ /*
+ * If the IOCB_FLAG_RESFD flag of aio_flags is set, get an
+ * instance of the file* now. The file descriptor must be
+ * an eventfd() fd, and will be signaled for each completed
+ * event using the eventfd_signal() function.
+ */
+ req->ki_eventfd = eventfd_ctx_fdget((int) iocb->aio_resfd);
+ if (IS_ERR(req->ki_eventfd)) {
+ ret = PTR_ERR(req->ki_eventfd);
+ req->ki_eventfd = NULL;
+ goto out_put_req;
+ }
+ }
+
ret = put_user(req->ki_key, &user_iocb->aio_key);
if (unlikely(ret)) {
dprintk("EFAULT: aio_key\n");
req->ki_buf = (char __user *)(unsigned long)iocb->aio_buf;
req->ki_left = req->ki_nbytes = iocb->aio_nbytes;
req->ki_opcode = iocb->aio_lio_opcode;
- init_waitqueue_func_entry(&req->ki_wait, aio_wake_function);
- INIT_LIST_HEAD(&req->ki_wait.task_list);
- req->ki_retried = 0;
- ret = aio_setup_iocb(req);
+ ret = aio_setup_iocb(req, compat);
if (ret)
goto out_put_req;
spin_lock_irq(&ctx->ctx_lock);
- if (likely(list_empty(&ctx->run_list))) {
- aio_run_iocb(req);
- } else {
- list_add_tail(&req->ki_run_list, &ctx->run_list);
+ /*
+ * We could have raced with io_destroy() and are currently holding a
+ * reference to ctx which should be destroyed. We cannot submit IO
+ * since ctx gets freed as soon as io_submit() puts its reference. The
+ * check here is reliable: io_destroy() sets ctx->dead before waiting
+ * for outstanding IO and the barrier between these two is realized by
+ * unlock of mm->ioctx_lock and lock of ctx->ctx_lock. Analogously we
+ * increment ctx->reqs_active before checking for ctx->dead and the
+ * barrier is realized by unlock and lock of ctx->ctx_lock. Thus if we
+ * don't see ctx->dead set here, io_destroy() waits for our IO to
+ * finish.
+ */
+ if (ctx->dead) {
+ spin_unlock_irq(&ctx->ctx_lock);
+ ret = -EINVAL;
+ goto out_put_req;
+ }
+ aio_run_iocb(req);
+ if (!list_empty(&ctx->run_list)) {
/* drain the run list */
while (__aio_run_iocbs(ctx))
;
}
spin_unlock_irq(&ctx->ctx_lock);
+
aio_put_req(req); /* drop extra ref to req */
return 0;
return ret;
}
-/* sys_io_submit:
- * Queue the nr iocbs pointed to by iocbpp for processing. Returns
- * the number of iocbs queued. May return -EINVAL if the aio_context
- * specified by ctx_id is invalid, if nr is < 0, if the iocb at
- * *iocbpp[0] is not properly initialized, if the operation specified
- * is invalid for the file descriptor in the iocb. May fail with
- * -EFAULT if any of the data structures point to invalid data. May
- * fail with -EBADF if the file descriptor specified in the first
- * iocb is invalid. May fail with -EAGAIN if insufficient resources
- * are available to queue any iocbs. Will return 0 if nr is 0. Will
- * fail with -ENOSYS if not implemented.
- */
-asmlinkage long sys_io_submit(aio_context_t ctx_id, long nr,
- struct iocb __user * __user *iocbpp)
+long do_io_submit(aio_context_t ctx_id, long nr,
+ struct iocb __user *__user *iocbpp, bool compat)
{
struct kioctx *ctx;
long ret = 0;
int i;
+ struct blk_plug plug;
if (unlikely(nr < 0))
return -EINVAL;
+ if (unlikely(nr > LONG_MAX/sizeof(*iocbpp)))
+ nr = LONG_MAX/sizeof(*iocbpp);
+
if (unlikely(!access_ok(VERIFY_READ, iocbpp, (nr*sizeof(*iocbpp)))))
return -EFAULT;
return -EINVAL;
}
+ blk_start_plug(&plug);
+
/*
* AKPM: should this return a partial result if some of the IOs were
* successfully submitted?
break;
}
- ret = io_submit_one(ctx, user_iocb, &tmp);
+ ret = io_submit_one(ctx, user_iocb, &tmp, compat);
if (ret)
break;
}
+ blk_finish_plug(&plug);
put_ioctx(ctx);
return i ? i : ret;
}
+/* sys_io_submit:
+ * Queue the nr iocbs pointed to by iocbpp for processing. Returns
+ * the number of iocbs queued. May return -EINVAL if the aio_context
+ * specified by ctx_id is invalid, if nr is < 0, if the iocb at
+ * *iocbpp[0] is not properly initialized, if the operation specified
+ * is invalid for the file descriptor in the iocb. May fail with
+ * -EFAULT if any of the data structures point to invalid data. May
+ * fail with -EBADF if the file descriptor specified in the first
+ * iocb is invalid. May fail with -EAGAIN if insufficient resources
+ * are available to queue any iocbs. Will return 0 if nr is 0. Will
+ * fail with -ENOSYS if not implemented.
+ */
+SYSCALL_DEFINE3(io_submit, aio_context_t, ctx_id, long, nr,
+ struct iocb __user * __user *, iocbpp)
+{
+ return do_io_submit(ctx_id, nr, iocbpp, 0);
+}
+
/* lookup_kiocb
* Finds a given iocb for cancellation.
- * MUST be called with ctx->ctx_lock held.
*/
static struct kiocb *lookup_kiocb(struct kioctx *ctx, struct iocb __user *iocb,
u32 key)
{
struct list_head *pos;
+
+ assert_spin_locked(&ctx->ctx_lock);
+
/* TODO: use a hash or array, this sucks. */
list_for_each(pos, &ctx->active_reqs) {
struct kiocb *kiocb = list_kiocb(pos);
* invalid. May fail with -EAGAIN if the iocb specified was not
* cancelled. Will fail with -ENOSYS if not implemented.
*/
-asmlinkage long sys_io_cancel(aio_context_t ctx_id, struct iocb __user *iocb,
- struct io_event __user *result)
+SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb,
+ struct io_event __user *, result)
{
int (*cancel)(struct kiocb *iocb, struct io_event *res);
struct kioctx *ctx;
ret = -EFAULT;
}
} else
- printk(KERN_DEBUG "iocb has no cancel operation\n");
+ ret = -EINVAL;
put_ioctx(ctx);
/* io_getevents:
* Attempts to read at least min_nr events and up to nr events from
- * the completion queue for the aio_context specified by ctx_id. May
- * fail with -EINVAL if ctx_id is invalid, if min_nr is out of range,
- * if nr is out of range, if when is out of range. May fail with
- * -EFAULT if any of the memory specified to is invalid. May return
- * 0 or < min_nr if no events are available and the timeout specified
- * by when has elapsed, where when == NULL specifies an infinite
- * timeout. Note that the timeout pointed to by when is relative and
- * will be updated if not NULL and the operation blocks. Will fail
- * with -ENOSYS if not implemented.
+ * the completion queue for the aio_context specified by ctx_id. If
+ * it succeeds, the number of read events is returned. May fail with
+ * -EINVAL if ctx_id is invalid, if min_nr is out of range, if nr is
+ * out of range, if timeout is out of range. May fail with -EFAULT
+ * if any of the memory specified is invalid. May return 0 or
+ * < min_nr if the timeout specified by timeout has elapsed
+ * before sufficient events are available, where timeout == NULL
+ * specifies an infinite timeout. Note that the timeout pointed to by
+ * timeout is relative and will be updated if not NULL and the
+ * operation blocks. Will fail with -ENOSYS if not implemented.
*/
-asmlinkage long sys_io_getevents(aio_context_t ctx_id,
- long min_nr,
- long nr,
- struct io_event __user *events,
- struct timespec __user *timeout)
+SYSCALL_DEFINE5(io_getevents, aio_context_t, ctx_id,
+ long, min_nr,
+ long, nr,
+ struct io_event __user *, events,
+ struct timespec __user *, timeout)
{
struct kioctx *ioctx = lookup_ioctx(ctx_id);
long ret = -EINVAL;
if (likely(ioctx)) {
- if (likely(min_nr <= nr && min_nr >= 0 && nr >= 0))
+ if (likely(min_nr <= nr && min_nr >= 0))
ret = read_events(ioctx, min_nr, nr, events, timeout);
put_ioctx(ioctx);
}
+ asmlinkage_protect(5, ret, ctx_id, min_nr, nr, events, timeout);
return ret;
}
-
-__initcall(aio_setup);
-
-EXPORT_SYMBOL(aio_complete);
-EXPORT_SYMBOL(aio_put_req);
-EXPORT_SYMBOL(wait_on_sync_kiocb);
Code Review / linux-2.6.git / blobdiff