summaryrefslogtreecommitdiff
path: root/net/sunrpc/cache.c
diff options
context:
space:
mode:
authorRoberto Bergantinos Corpas <rbergant@redhat.com>2020-11-27 21:38:31 +0300
committerChuck Lever <chuck.lever@oracle.com>2020-12-09 17:38:34 +0300
commit4b5cff7ed8afcdd35bfff39ab503342900ec80c6 (patch)
tree13ef5d7ed5efeb40b0fe7c61120703f49cb1761b /net/sunrpc/cache.c
parent4420440c57892779f265108f46f83832a88ca795 (diff)
downloadlinux-4b5cff7ed8afcdd35bfff39ab503342900ec80c6.tar.xz
sunrpc: clean-up cache downcall
We can simplify code around cache_downcall unifying memory allocations using kvmalloc. This has the benefit of getting rid of cache_slow_downcall (and queue_io_mutex), and also matches userland allocation size and limits. Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Diffstat (limited to 'net/sunrpc/cache.c')
-rw-r--r--net/sunrpc/cache.c41
1 files changed, 11 insertions, 30 deletions
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 20c93b68505e..1a2c1c44bb00 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -778,7 +778,6 @@ void cache_clean_deferred(void *owner)
*/
static DEFINE_SPINLOCK(queue_lock);
-static DEFINE_MUTEX(queue_io_mutex);
struct cache_queue {
struct list_head list;
@@ -906,44 +905,26 @@ static ssize_t cache_do_downcall(char *kaddr, const char __user *buf,
return ret;
}
-static ssize_t cache_slow_downcall(const char __user *buf,
- size_t count, struct cache_detail *cd)
-{
- static char write_buf[32768]; /* protected by queue_io_mutex */
- ssize_t ret = -EINVAL;
-
- if (count >= sizeof(write_buf))
- goto out;
- mutex_lock(&queue_io_mutex);
- ret = cache_do_downcall(write_buf, buf, count, cd);
- mutex_unlock(&queue_io_mutex);
-out:
- return ret;
-}
-
static ssize_t cache_downcall(struct address_space *mapping,
const char __user *buf,
size_t count, struct cache_detail *cd)
{
- struct page *page;
- char *kaddr;
+ char *write_buf;
ssize_t ret = -ENOMEM;
- if (count >= PAGE_SIZE)
- goto out_slow;
+ if (count >= 32768) { /* 32k is max userland buffer, lets check anyway */
+ ret = -EINVAL;
+ goto out;
+ }
- page = find_or_create_page(mapping, 0, GFP_KERNEL);
- if (!page)
- goto out_slow;
+ write_buf = kvmalloc(count + 1, GFP_KERNEL);
+ if (!write_buf)
+ goto out;
- kaddr = kmap(page);
- ret = cache_do_downcall(kaddr, buf, count, cd);
- kunmap(page);
- unlock_page(page);
- put_page(page);
+ ret = cache_do_downcall(write_buf, buf, count, cd);
+ kvfree(write_buf);
+out:
return ret;
-out_slow:
- return cache_slow_downcall(buf, count, cd);
}
static ssize_t cache_write(struct file *filp, const char __user *buf,