RPC channel buffer size for slow case (user buffer bigger than
one page) can be converted into dymanic and also allows us to
prescind from queue_io_mutex
Signed-off-by: Roberto Bergantinos Corpas <rbergant@xxxxxxxxxx>
---
net/sunrpc/cache.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index baef5ee43dbb..325393f75e17 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -777,7 +777,6 @@ void cache_clean_deferred(void *owner)
*/
static DEFINE_SPINLOCK(queue_lock);
-static DEFINE_MUTEX(queue_io_mutex);
struct cache_queue {
struct list_head list;
@@ -908,14 +907,18 @@ static ssize_t cache_do_downcall(char *kaddr, const char __user *buf,
static ssize_t cache_slow_downcall(const char __user *buf,
size_t count, struct cache_detail *cd)
{
- static char write_buf[8192]; /* protected by queue_io_mutex */
+ char *write_buf;
ssize_t ret = -EINVAL;
- if (count >= sizeof(write_buf))
+ if (count >= 32768) /* 32k is max userland buffer, lets check anyway */
goto out;
- mutex_lock(&queue_io_mutex);
+
+ write_buf = kvmalloc(count + 1, GFP_KERNEL);
+ if (!write_buf)
+ return -ENOMEM;
+
ret = cache_do_downcall(write_buf, buf, count, cd);
- mutex_unlock(&queue_io_mutex);
+ kvfree(write_buf);
out:
return ret;
}
--
2.21.0
