unsigned id;
};
+/*
+ * We use ki_cancel == KIOCB_CANCELLED to indicate that a kiocb has been either
+ * cancelled or completed (this makes a certain amount of sense because
+ * successful cancellation - io_cancel() - does deliver the completion to
+ * userspace).
+ *
+ * And since most things don't implement kiocb cancellation and we'd really like
+ * kiocb completion to be lockless when possible, we use ki_cancel to
+ * synchronize cancellation and completion - we only set it to KIOCB_CANCELLED
+ * with xchg() or cmpxchg(), see batch_complete_aio() and kiocb_cancel().
+ */
+#define KIOCB_CANCELLED ((void *) (~0ULL))
+
+struct aio_kiocb {
+ struct kiocb common;
+
+ struct kioctx *ki_ctx;
+ kiocb_cancel_fn *ki_cancel;
+
+ struct iocb __user *ki_user_iocb; /* user's aiocb */
+ __u64 ki_user_data; /* user's data for completion */
+
+ struct list_head ki_list; /* the aio core uses this
+ * for cancellation */
+
+ /*
+ * If the aio_resfd field of the userspace iocb is not zero,
+ * this is the underlying eventfd context to deliver events to.
+ */
+ struct eventfd_ctx *ki_eventfd;
+};
+
/*------ sysctl variables----*/
static DEFINE_SPINLOCK(aio_nr_lock);
unsigned long aio_nr; /* current system wide number of aio requests */
if (IS_ERR(aio_mnt))
panic("Failed to create aio fs mount.");
- kiocb_cachep = KMEM_CACHE(kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
+ kiocb_cachep = KMEM_CACHE(aio_kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC);
pr_debug("sizeof(struct page) = %zu\n", sizeof(struct page));
#define AIO_EVENTS_FIRST_PAGE ((PAGE_SIZE - sizeof(struct aio_ring)) / sizeof(struct io_event))
#define AIO_EVENTS_OFFSET (AIO_EVENTS_PER_PAGE - AIO_EVENTS_FIRST_PAGE)
-void kiocb_set_cancel_fn(struct kiocb *req, kiocb_cancel_fn *cancel)
+void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel)
{
+ struct aio_kiocb *req = container_of(iocb, struct aio_kiocb, common);
struct kioctx *ctx = req->ki_ctx;
unsigned long flags;
}
EXPORT_SYMBOL(kiocb_set_cancel_fn);
-static int kiocb_cancel(struct kiocb *kiocb)
+static int kiocb_cancel(struct aio_kiocb *kiocb)
{
kiocb_cancel_fn *old, *cancel;
cancel = cmpxchg(&kiocb->ki_cancel, old, KIOCB_CANCELLED);
} while (cancel != old);
- return cancel(kiocb);
+ return cancel(&kiocb->common);
}
static void free_ioctx(struct work_struct *work)
static void free_ioctx_users(struct percpu_ref *ref)
{
struct kioctx *ctx = container_of(ref, struct kioctx, users);
- struct kiocb *req;
+ struct aio_kiocb *req;
spin_lock_irq(&ctx->ctx_lock);
while (!list_empty(&ctx->active_reqs)) {
req = list_first_entry(&ctx->active_reqs,
- struct kiocb, ki_list);
+ struct aio_kiocb, ki_list);
list_del_init(&req->ki_list);
kiocb_cancel(req);
nr_events *= 2;
/* Prevent overflows */
- if ((nr_events > (0x10000000U / sizeof(struct io_event))) ||
- (nr_events > (0x10000000U / sizeof(struct kiocb)))) {
+ if (nr_events > (0x10000000U / sizeof(struct io_event))) {
pr_debug("ENOMEM: nr_events too high\n");
return ERR_PTR(-EINVAL);
}
return 0;
}
-/* wait_on_sync_kiocb:
- * Waits on the given sync kiocb to complete.
- */
-ssize_t wait_on_sync_kiocb(struct kiocb *req)
-{
- while (!req->ki_ctx) {
- set_current_state(TASK_UNINTERRUPTIBLE);
- if (req->ki_ctx)
- break;
- io_schedule();
- }
- __set_current_state(TASK_RUNNING);
- return req->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 io_* syscalls to be
* Allocate a slot for an aio request.
* Returns NULL if no requests are free.
*/
-static inline struct kiocb *aio_get_req(struct kioctx *ctx)
+static inline struct aio_kiocb *aio_get_req(struct kioctx *ctx)
{
- struct kiocb *req;
+ struct aio_kiocb *req;
if (!get_reqs_available(ctx)) {
user_refill_reqs_available(ctx);
return NULL;
}
-static void kiocb_free(struct kiocb *req)
+static void kiocb_free(struct aio_kiocb *req)
{
- if (req->ki_filp)
- fput(req->ki_filp);
+ if (req->common.ki_filp)
+ fput(req->common.ki_filp);
if (req->ki_eventfd != NULL)
eventfd_ctx_put(req->ki_eventfd);
kmem_cache_free(kiocb_cachep, req);
/* aio_complete
* Called when the io request on the given iocb is complete.
*/
-void aio_complete(struct kiocb *iocb, long res, long res2)
+static void aio_complete(struct kiocb *kiocb, long res, long res2)
{
+ struct aio_kiocb *iocb = container_of(kiocb, struct aio_kiocb, common);
struct kioctx *ctx = iocb->ki_ctx;
struct aio_ring *ring;
struct io_event *ev_page, *event;
* 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)) {
- iocb->ki_user_data = res;
- smp_wmb();
- iocb->ki_ctx = ERR_PTR(-EXDEV);
- wake_up_process(iocb->ki_obj.tsk);
- return;
- }
+ BUG_ON(is_sync_kiocb(kiocb));
if (iocb->ki_list.next) {
unsigned long flags;
ev_page = kmap_atomic(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]);
event = ev_page + pos % AIO_EVENTS_PER_PAGE;
- event->obj = (u64)(unsigned long)iocb->ki_obj.user;
+ event->obj = (u64)(unsigned long)iocb->ki_user_iocb;
event->data = iocb->ki_user_data;
event->res = res;
event->res2 = res2;
flush_dcache_page(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]);
pr_debug("%p[%u]: %p: %p %Lx %lx %lx\n",
- ctx, tail, iocb, iocb->ki_obj.user, iocb->ki_user_data,
+ ctx, tail, iocb, iocb->ki_user_iocb, iocb->ki_user_data,
res, res2);
/* after flagging the request as done, we
percpu_ref_put(&ctx->reqs);
}
-EXPORT_SYMBOL(aio_complete);
/* aio_read_events_ring
* Pull an event off of the ioctx's event ring. Returns the number of
return -EINVAL;
}
-typedef ssize_t (aio_rw_op)(struct kiocb *, const struct iovec *,
- unsigned long, loff_t);
typedef ssize_t (rw_iter_op)(struct kiocb *, struct iov_iter *);
-static ssize_t aio_setup_vectored_rw(struct kiocb *kiocb,
- int rw, char __user *buf,
- unsigned long *nr_segs,
- struct iovec **iovec,
- bool compat)
+static int aio_setup_vectored_rw(int rw, char __user *buf, size_t len,
+ struct iovec **iovec,
+ bool compat,
+ struct iov_iter *iter)
{
- ssize_t ret;
-
- *nr_segs = kiocb->ki_nbytes;
-
#ifdef CONFIG_COMPAT
if (compat)
- ret = compat_rw_copy_check_uvector(rw,
+ return compat_import_iovec(rw,
(struct compat_iovec __user *)buf,
- *nr_segs, UIO_FASTIOV, *iovec, iovec);
- else
+ len, UIO_FASTIOV, iovec, iter);
#endif
- ret = rw_copy_check_uvector(rw,
- (struct iovec __user *)buf,
- *nr_segs, UIO_FASTIOV, *iovec, iovec);
- if (ret < 0)
- return ret;
-
- /* ki_nbytes now reflect bytes instead of segs */
- kiocb->ki_nbytes = ret;
- return 0;
-}
-
-static ssize_t aio_setup_single_vector(struct kiocb *kiocb,
- int rw, char __user *buf,
- unsigned long *nr_segs,
- struct iovec *iovec)
-{
- if (unlikely(!access_ok(!rw, buf, kiocb->ki_nbytes)))
- return -EFAULT;
-
- iovec->iov_base = buf;
- iovec->iov_len = kiocb->ki_nbytes;
- *nr_segs = 1;
- return 0;
+ return import_iovec(rw, (struct iovec __user *)buf,
+ len, UIO_FASTIOV, iovec, iter);
}
/*
* Performs the initial checks and io submission.
*/
static ssize_t aio_run_iocb(struct kiocb *req, unsigned opcode,
- char __user *buf, bool compat)
+ char __user *buf, size_t len, bool compat)
{
struct file *file = req->ki_filp;
ssize_t ret;
- unsigned long nr_segs;
int rw;
fmode_t mode;
- aio_rw_op *rw_op;
rw_iter_op *iter_op;
struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
struct iov_iter iter;
case IOCB_CMD_PREADV:
mode = FMODE_READ;
rw = READ;
- rw_op = file->f_op->aio_read;
iter_op = file->f_op->read_iter;
goto rw_common;
case IOCB_CMD_PWRITEV:
mode = FMODE_WRITE;
rw = WRITE;
- rw_op = file->f_op->aio_write;
iter_op = file->f_op->write_iter;
goto rw_common;
rw_common:
if (unlikely(!(file->f_mode & mode)))
return -EBADF;
- if (!rw_op && !iter_op)
+ if (!iter_op)
return -EINVAL;
- ret = (opcode == IOCB_CMD_PREADV ||
- opcode == IOCB_CMD_PWRITEV)
- ? aio_setup_vectored_rw(req, rw, buf, &nr_segs,
- &iovec, compat)
- : aio_setup_single_vector(req, rw, buf, &nr_segs,
- iovec);
+ if (opcode == IOCB_CMD_PREADV || opcode == IOCB_CMD_PWRITEV)
+ ret = aio_setup_vectored_rw(rw, buf, len,
+ &iovec, compat, &iter);
+ else {
+ ret = import_single_range(rw, buf, len, iovec, &iter);
+ iovec = NULL;
+ }
if (!ret)
- ret = rw_verify_area(rw, file, &req->ki_pos, req->ki_nbytes);
+ ret = rw_verify_area(rw, file, &req->ki_pos,
+ iov_iter_count(&iter));
if (ret < 0) {
- if (iovec != inline_vecs)
- kfree(iovec);
+ kfree(iovec);
return ret;
}
- req->ki_nbytes = ret;
-
- /* XXX: move/kill - rw_verify_area()? */
- /* This matches the pread()/pwrite() logic */
- if (req->ki_pos < 0) {
- ret = -EINVAL;
- break;
- }
+ len = ret;
if (rw == WRITE)
file_start_write(file);
- if (iter_op) {
- iov_iter_init(&iter, rw, iovec, nr_segs, req->ki_nbytes);
- ret = iter_op(req, &iter);
- } else {
- ret = rw_op(req, iovec, nr_segs, req->ki_pos);
- }
+ ret = iter_op(req, &iter);
if (rw == WRITE)
file_end_write(file);
+ kfree(iovec);
break;
case IOCB_CMD_FDSYNC:
return -EINVAL;
}
- if (iovec != inline_vecs)
- kfree(iovec);
-
if (ret != -EIOCBQUEUED) {
/*
* There's no easy way to restart the syscall since other AIO's
static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
struct iocb *iocb, bool compat)
{
- struct kiocb *req;
+ struct aio_kiocb *req;
ssize_t ret;
/* enforce forwards compatibility on users */
if (unlikely(!req))
return -EAGAIN;
- req->ki_filp = fget(iocb->aio_fildes);
- if (unlikely(!req->ki_filp)) {
+ req->common.ki_filp = fget(iocb->aio_fildes);
+ if (unlikely(!req->common.ki_filp)) {
ret = -EBADF;
goto out_put_req;
}
+ req->common.ki_pos = iocb->aio_offset;
+ req->common.ki_complete = aio_complete;
+ req->common.ki_flags = 0;
if (iocb->aio_flags & IOCB_FLAG_RESFD) {
/*
req->ki_eventfd = NULL;
goto out_put_req;
}
+
+ req->common.ki_flags |= IOCB_EVENTFD;
}
ret = put_user(KIOCB_KEY, &user_iocb->aio_key);
goto out_put_req;
}
- req->ki_obj.user = user_iocb;
+ req->ki_user_iocb = user_iocb;
req->ki_user_data = iocb->aio_data;
- req->ki_pos = iocb->aio_offset;
- req->ki_nbytes = iocb->aio_nbytes;
- ret = aio_run_iocb(req, iocb->aio_lio_opcode,
+ ret = aio_run_iocb(&req->common, iocb->aio_lio_opcode,
(char __user *)(unsigned long)iocb->aio_buf,
+ iocb->aio_nbytes,
compat);
if (ret)
goto out_put_req;
/* lookup_kiocb
* Finds a given iocb for cancellation.
*/
-static struct kiocb *lookup_kiocb(struct kioctx *ctx, struct iocb __user *iocb,
- u32 key)
+static struct aio_kiocb *
+lookup_kiocb(struct kioctx *ctx, struct iocb __user *iocb, u32 key)
{
- struct list_head *pos;
+ struct aio_kiocb *kiocb;
assert_spin_locked(&ctx->ctx_lock);
return NULL;
/* TODO: use a hash or array, this sucks. */
- list_for_each(pos, &ctx->active_reqs) {
- struct kiocb *kiocb = list_kiocb(pos);
- if (kiocb->ki_obj.user == iocb)
+ list_for_each_entry(kiocb, &ctx->active_reqs, ki_list) {
+ if (kiocb->ki_user_iocb == iocb)
return kiocb;
}
return NULL;
struct io_event __user *, result)
{
struct kioctx *ctx;
- struct kiocb *kiocb;
+ struct aio_kiocb *kiocb;
u32 key;
int ret;
projects / linux-2.6-block.git / blobdiff