Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
io_uring/rsrc: cleanup io_pin_pages()
This function is overly convoluted with a goto error path, and checks
under the mmap_read_lock() that don't need to be at all. Rearrange it
a bit so the checks and errors fall out naturally, rather than needing
to jump around for it.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
+18
-21
+18
-21
io_uring/rsrc.c
+18
-21
io_uring/rsrc.c
···
1037
1037
{
1038
1038
unsigned long start, end, nr_pages;
1039
1039
struct page **pages = NULL;
1040
-
int pret, ret = -ENOMEM;
1040
+
int ret;
1041
1041
1042
1042
end = (ubuf + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
1043
1043
start = ubuf >> PAGE_SHIFT;
1044
1044
nr_pages = end - start;
1045
+
WARN_ON(!nr_pages);
1045
1046
1046
1047
pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
1047
1048
if (!pages)
1048
-
goto done;
1049
+
return ERR_PTR(-ENOMEM);
1049
1050
1050
-
ret = 0;
1051
1051
mmap_read_lock(current->mm);
1052
-
pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
1053
-
pages);
1054
-
if (pret == nr_pages)
1055
-
*npages = nr_pages;
1056
-
else
1057
-
ret = pret < 0 ? pret : -EFAULT;
1058
-
1052
+
ret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM, pages);
1059
1053
mmap_read_unlock(current->mm);
1060
-
if (ret) {
1054
+
1055
+
/* success, mapped all pages */
1056
+
if (ret == nr_pages) {
1057
+
*npages = nr_pages;
1058
+
return pages;
1059
+
}
1060
+
1061
+
/* partial map, or didn't map anything */
1062
+
if (ret >= 0) {
1061
1063
/* if we did partial map, release any pages we did get */
1062
-
if (pret > 0)
1063
-
unpin_user_pages(pages, pret);
1064
-
goto done;
1064
+
if (ret)
1065
+
unpin_user_pages(pages, ret);
1066
+
ret = -EFAULT;
1065
1067
}
1066
-
ret = 0;
1067
-
done:
1068
-
if (ret < 0) {
1069
-
kvfree(pages);
1070
-
pages = ERR_PTR(ret);
1071
-
}
1072
-
return pages;
1068
+
kvfree(pages);
1069
+
return ERR_PTR(ret);
1073
1070
}
1074
1071
1075
1072
static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,