The patch titled
aio: rework compat_sys_io_submit
has been added to the -mm tree. Its filename is
rework-compat_sys_io_submit.patch
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: aio: rework compat_sys_io_submit
From: Sébastien Dugué <sebastien.dugue@xxxxxxxx>
Cleanup compat_sys_io_submit by duplicating some of the native syscall logic
in the compat layer and directly calling io_submit_one() instead of fooling
the syscall into thinking it is called from a native 64-bit caller.
This eliminates:
- the overhead of copying the nr iocb pointers on the userspace stack
- the PAGE_SIZE/(sizeof(void *)) limit on the number of iocbs that
can be submitted.
This is also needed for the completion notification patch to avoid having to
rewrite each iocb on the caller stack for io_submit_one() to find the
sigevents.
Signed-off-by: Sébastien Dugué <sebastien.dugue@xxxxxxxx>
Cc: Bharata B Rao <bharata@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Suparna Bhattacharya <suparna@xxxxxxxxxx>
Cc: Zach Brown <zach.brown@xxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Badari Pulavarty <pbadari@xxxxxxxxxx>
Cc: Benjamin LaHaise <bcrl@xxxxxxxxxxxxxxx>
Cc: Jean Pierre Dion <jean-pierre.dion@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
fs/compat.c | 61 +++++++++++++++++++++++++++-----------------------
1 files changed, 34 insertions(+), 27 deletions(-)
diff -puN fs/compat.c~rework-compat_sys_io_submit fs/compat.c
--- a/fs/compat.c~rework-compat_sys_io_submit
+++ a/fs/compat.c
@@ -644,40 +644,47 @@ out:
return ret;
}
-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 *))
-
asmlinkage long
compat_sys_io_submit(aio_context_t ctx_id, int nr, u32 __user *iocb)
{
- struct iocb __user * __user *iocb64;
- long ret;
+ struct kioctx *ctx;
+ long ret = 0;
+ int i;
if (unlikely(nr < 0))
return -EINVAL;
- 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 = sys_io_submit(ctx_id, nr, iocb64);
- return ret;
+ if (unlikely(!access_ok(VERIFY_READ, iocb, (nr * sizeof(u32)))))
+ return -EFAULT;
+
+ ctx = lookup_ioctx(ctx_id);
+ if (unlikely(!ctx))
+ return -EINVAL;
+
+ for (i=0; i<nr; i++) {
+ compat_uptr_t uptr;
+ struct iocb __user *user_iocb;
+ struct iocb tmp;
+
+ if (unlikely(get_user(uptr, iocb + i))) {
+ ret = -EFAULT;
+ break;
+ }
+
+ user_iocb = compat_ptr(uptr);
+
+ if (unlikely(copy_from_user(&tmp, user_iocb, sizeof(tmp)))) {
+ ret = -EFAULT;
+ break;
+ }
+
+ ret = io_submit_one(ctx, user_iocb, &tmp);
+ if (ret)
+ break;
+ }
+
+ put_ioctx(ctx);
+ return i ? i: ret;
}
struct compat_ncp_mount_data {
_
Patches currently in -mm which might be from sebastien.dugue@xxxxxxxx are
rework-compat_sys_io_submit.patch
fix-aioh-includes.patch
fix-access_ok-checks.patch
make-good_sigevent-non-static.patch
make-__sigqueue_free-and.patch
aio-completion-signal-notification.patch
add-listio-syscall-support.patch
-
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