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>

1 files changed, 45 insertions, 54 deletions

diff --git a/fs/aio.c b/fs/aio.c
index 90b46560f0ce..da859574c953 100644
--- 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