lkml.org 
[lkml]   [2020]   [Nov]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[PATCH 27/29] iov_iter: Split dup_iter()
From
Date
Split dup_iter() by type.

Signed-off-by: David Howells <dhowells@redhat.com>
---

lib/iov_iter.c | 49 +++++++++++++++++++++++++++++--------------------
1 file changed, 29 insertions(+), 20 deletions(-)

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index d8ef6c81c55f..ca0e94596eda 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -2078,26 +2078,35 @@ static int discard_npages(const struct iov_iter *i, int maxpages)
return 0;
}

-static const void *xxx_dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags)
+static const void *iovec_kvec_dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags)
{
*new = *old;
- if (unlikely(iov_iter_is_pipe(new))) {
- WARN_ON(1);
- return NULL;
- }
- if (unlikely(iov_iter_is_discard(new)))
- return NULL;
- if (iov_iter_is_bvec(new))
- return new->bvec = kmemdup(new->bvec,
- new->nr_segs * sizeof(struct bio_vec),
- flags);
- else
- /* iovec and kvec have identical layout */
- return new->iov = kmemdup(new->iov,
- new->nr_segs * sizeof(struct iovec),
+ /* iovec and kvec have identical layout */
+ return new->iov = kmemdup(new->iov,
+ new->nr_segs * sizeof(struct iovec),
+ flags);
+}
+
+static const void *bvec_dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags)
+{
+ *new = *old;
+ return new->bvec = kmemdup(new->bvec,
+ new->nr_segs * sizeof(struct bio_vec),
flags);
}

+static const void *discard_dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags)
+{
+ *new = *old;
+ return NULL;
+}
+
+static const void *no_dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags)
+{
+ WARN_ON(1);
+ return NULL;
+}
+
static int copy_compat_iovec_from_user(struct iovec *iov,
const struct iovec __user *uvec, unsigned long nr_segs)
{
@@ -2324,7 +2333,7 @@ static const struct iov_iter_ops iovec_iter_ops = {
.get_pages = iovec_get_pages,
.get_pages_alloc = iovec_get_pages_alloc,
.npages = iovec_npages,
- .dup_iter = xxx_dup_iter,
+ .dup_iter = iovec_kvec_dup_iter,
.for_each_range = xxx_for_each_range,
};

@@ -2358,7 +2367,7 @@ static const struct iov_iter_ops kvec_iter_ops = {
.get_pages = no_get_pages,
.get_pages_alloc = no_get_pages_alloc,
.npages = kvec_npages,
- .dup_iter = xxx_dup_iter,
+ .dup_iter = iovec_kvec_dup_iter,
.for_each_range = xxx_for_each_range,
};

@@ -2392,7 +2401,7 @@ static const struct iov_iter_ops bvec_iter_ops = {
.get_pages = bvec_get_pages,
.get_pages_alloc = bvec_get_pages_alloc,
.npages = bvec_npages,
- .dup_iter = xxx_dup_iter,
+ .dup_iter = bvec_dup_iter,
.for_each_range = xxx_for_each_range,
};

@@ -2426,7 +2435,7 @@ static const struct iov_iter_ops pipe_iter_ops = {
.get_pages = pipe_get_pages,
.get_pages_alloc = pipe_get_pages_alloc,
.npages = pipe_npages,
- .dup_iter = xxx_dup_iter,
+ .dup_iter = no_dup_iter,
.for_each_range = xxx_for_each_range,
};

@@ -2460,6 +2469,6 @@ static const struct iov_iter_ops discard_iter_ops = {
.get_pages = no_get_pages,
.get_pages_alloc = no_get_pages_alloc,
.npages = discard_npages,
- .dup_iter = xxx_dup_iter,
+ .dup_iter = discard_dup_iter,
.for_each_range = xxx_for_each_range,
};

\
 
 \ /
  Last update: 2020-11-21 15:21    [W:0.242 / U:31.428 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site