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Diffstat (limited to 'fs/pipe.c')
-rw-r--r--fs/pipe.c52
1 files changed, 41 insertions, 11 deletions
diff --git a/fs/pipe.c b/fs/pipe.c
index 8aada8e426f..109a102c150 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -15,6 +15,7 @@
#include <linux/pipe_fs_i.h>
#include <linux/uio.h>
#include <linux/highmem.h>
+#include <linux/pagemap.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
@@ -94,11 +95,20 @@ static void anon_pipe_buf_release(struct pipe_inode_info *info, struct pipe_buff
{
struct page *page = buf->page;
- if (info->tmp_page) {
- __free_page(page);
+ /*
+ * If nobody else uses this page, and we don't already have a
+ * temporary page, let's keep track of it as a one-deep
+ * allocation cache
+ */
+ if (page_count(page) == 1 && !info->tmp_page) {
+ info->tmp_page = page;
return;
}
- info->tmp_page = page;
+
+ /*
+ * Otherwise just release our reference to it
+ */
+ page_cache_release(page);
}
static void *anon_pipe_buf_map(struct file *file, struct pipe_inode_info *info, struct pipe_buffer *buf)
@@ -111,11 +121,19 @@ static void anon_pipe_buf_unmap(struct pipe_inode_info *info, struct pipe_buffer
kunmap(buf->page);
}
+static int anon_pipe_buf_steal(struct pipe_inode_info *info,
+ struct pipe_buffer *buf)
+{
+ buf->stolen = 1;
+ return 0;
+}
+
static struct pipe_buf_operations anon_pipe_buf_ops = {
.can_merge = 1,
.map = anon_pipe_buf_map,
.unmap = anon_pipe_buf_unmap,
.release = anon_pipe_buf_release,
+ .steal = anon_pipe_buf_steal,
};
static ssize_t
@@ -152,6 +170,11 @@ pipe_readv(struct file *filp, const struct iovec *_iov,
chars = total_len;
addr = ops->map(filp, info, buf);
+ if (IS_ERR(addr)) {
+ if (!ret)
+ ret = PTR_ERR(addr);
+ break;
+ }
error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars);
ops->unmap(info, buf);
if (unlikely(error)) {
@@ -254,8 +277,16 @@ pipe_writev(struct file *filp, const struct iovec *_iov,
struct pipe_buf_operations *ops = buf->ops;
int offset = buf->offset + buf->len;
if (ops->can_merge && offset + chars <= PAGE_SIZE) {
- void *addr = ops->map(filp, info, buf);
- int error = pipe_iov_copy_from_user(offset + addr, iov, chars);
+ void *addr;
+ int error;
+
+ addr = ops->map(filp, info, buf);
+ if (IS_ERR(addr)) {
+ error = PTR_ERR(addr);
+ goto out;
+ }
+ error = pipe_iov_copy_from_user(offset + addr, iov,
+ chars);
ops->unmap(info, buf);
ret = error;
do_wakeup = 1;
@@ -568,7 +599,7 @@ pipe_rdwr_open(struct inode *inode, struct file *filp)
* The file_operations structs are not static because they
* are also used in linux/fs/fifo.c to do operations on FIFOs.
*/
-struct file_operations read_fifo_fops = {
+const struct file_operations read_fifo_fops = {
.llseek = no_llseek,
.read = pipe_read,
.readv = pipe_readv,
@@ -580,7 +611,7 @@ struct file_operations read_fifo_fops = {
.fasync = pipe_read_fasync,
};
-struct file_operations write_fifo_fops = {
+const struct file_operations write_fifo_fops = {
.llseek = no_llseek,
.read = bad_pipe_r,
.write = pipe_write,
@@ -592,7 +623,7 @@ struct file_operations write_fifo_fops = {
.fasync = pipe_write_fasync,
};
-struct file_operations rdwr_fifo_fops = {
+const struct file_operations rdwr_fifo_fops = {
.llseek = no_llseek,
.read = pipe_read,
.readv = pipe_readv,
@@ -662,10 +693,9 @@ struct inode* pipe_new(struct inode* inode)
{
struct pipe_inode_info *info;
- info = kmalloc(sizeof(struct pipe_inode_info), GFP_KERNEL);
+ info = kzalloc(sizeof(struct pipe_inode_info), GFP_KERNEL);
if (!info)
goto fail_page;
- memset(info, 0, sizeof(*info));
inode->i_pipe = info;
init_waitqueue_head(PIPE_WAIT(*inode));
@@ -676,7 +706,7 @@ fail_page:
return NULL;
}
-static struct vfsmount *pipe_mnt;
+static struct vfsmount *pipe_mnt __read_mostly;
static int pipefs_delete_dentry(struct dentry *dentry)
{
return 1;