aio: fold do_io_submit() into callers

get rid of insane "copy array of 32bit pointers into an array of
native ones" glue.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/aio.c b/fs/aio.c
index 90b4656..da85957 100644 (file)
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1818,8 +1818,20 @@ out_put_req:
        return ret;
 }
 
-static long do_io_submit(aio_context_t ctx_id, long nr,
-                         struct iocb __user *__user *iocbpp, bool compat)
+/* 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)
 {
        struct kioctx *ctx;
        long ret = 0;
@@ -1832,9 +1844,6 @@ static long do_io_submit(aio_context_t ctx_id, long nr,
        if (unlikely(nr > LONG_MAX/sizeof(*iocbpp)))
                nr = LONG_MAX/sizeof(*iocbpp);
 
-       if (unlikely(!access_ok(VERIFY_READ, iocbpp, (nr*sizeof(*iocbpp)))))
-               return -EFAULT;
-
        ctx = lookup_ioctx(ctx_id);
        if (unlikely(!ctx)) {
                pr_debug("EINVAL: invalid context id\n");
@@ -1842,20 +1851,15 @@ static long do_io_submit(aio_context_t ctx_id, long nr,
        }
 
        blk_start_plug(&plug);
-
-       /*
-        * AKPM: should this return a partial result if some of the IOs were
-        * successfully submitted?
-        */
-       for (i=0; i<nr; i++) {
+       for (i = 0; i < nr; i++) {
                struct iocb __user *user_iocb;
 
-               if (unlikely(__get_user(user_iocb, iocbpp + i))) {
+               if (unlikely(get_user(user_iocb, iocbpp + i))) {
                        ret = -EFAULT;
                        break;
                }
 
-               ret = io_submit_one(ctx, user_iocb, compat);
+               ret = io_submit_one(ctx, user_iocb, false);
                if (ret)
                        break;
        }
@@ -1865,47 +1869,16 @@ static long do_io_submit(aio_context_t ctx_id, long nr,
        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);
-}
-
 #ifdef CONFIG_COMPAT
-static inline long
-copy_iocb(long nr, u32 __user *ptr32, struct iocb __user * __user *ptr64)
-{
-       compat_uptr_t uptr;
-       int i;
-
-       for (i = 0; i < nr; ++i) {
-               if (get_user(uptr, ptr32 + i))
-                       return -EFAULT;
-               if (put_user(compat_ptr(uptr), ptr64 + i))
-                       return -EFAULT;
-       }
-       return 0;
-}
-
 #define MAX_AIO_SUBMITS        (PAGE_SIZE/sizeof(struct iocb *))
 
 COMPAT_SYSCALL_DEFINE3(io_submit, compat_aio_context_t, ctx_id,
-                      int, nr, u32 __user *, iocb)
+                      int, nr, compat_uptr_t __user *, iocbpp)
 {
-       struct iocb __user * __user *iocb64;
-       long ret;
+       struct kioctx *ctx;
+       long ret = 0;
+       int i = 0;
+       struct blk_plug plug;
 
        if (unlikely(nr < 0))
                return -EINVAL;
@@ -1913,11 +1886,29 @@ COMPAT_SYSCALL_DEFINE3(io_submit, compat_aio_context_t, ctx_id,
        if (nr > MAX_AIO_SUBMITS)
                nr = MAX_AIO_SUBMITS;
 
-       iocb64 = compat_alloc_user_space(nr * sizeof(*iocb64));
-       ret = copy_iocb(nr, iocb, iocb64);
-       if (!ret)
-               ret = do_io_submit(ctx_id, nr, iocb64, 1);
-       return ret;
+       ctx = lookup_ioctx(ctx_id);
+       if (unlikely(!ctx)) {
+               pr_debug("EINVAL: invalid context id\n");
+               return -EINVAL;
+       }
+
+       blk_start_plug(&plug);
+       for (i = 0; i < nr; i++) {
+               compat_uptr_t user_iocb;
+
+               if (unlikely(get_user(user_iocb, iocbpp + i))) {
+                       ret = -EFAULT;
+                       break;
+               }
+
+               ret = io_submit_one(ctx, compat_ptr(user_iocb), true);
+               if (ret)
+                       break;
+       }
+       blk_finish_plug(&plug);
+
+       percpu_ref_put(&ctx->users);
+       return i ? i : ret;
 }
 #endif