#include <linux/uio.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
+#include <linux/audit.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
page_cache_release(page);
}
+/**
+ * generic_pipe_buf_map - virtually map a pipe buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer that should be mapped
+ * @atomic: whether to use an atomic map
+ *
+ * Description:
+ * This function returns a kernel virtual address mapping for the
+ * passed in @pipe_buffer. If @atomic is set, an atomic map is provided
+ * and the caller has to be careful not to fault before calling
+ * the unmap function.
+ *
+ * Note that this function occupies KM_USER0 if @atomic != 0.
+ */
void *generic_pipe_buf_map(struct pipe_inode_info *pipe,
struct pipe_buffer *buf, int atomic)
{
return kmap(buf->page);
}
+/**
+ * generic_pipe_buf_unmap - unmap a previously mapped pipe buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer that should be unmapped
+ * @map_data: the data that the mapping function returned
+ *
+ * Description:
+ * This function undoes the mapping that ->map() provided.
+ */
void generic_pipe_buf_unmap(struct pipe_inode_info *pipe,
struct pipe_buffer *buf, void *map_data)
{
kunmap(buf->page);
}
+/**
+ * generic_pipe_buf_steal - attempt to take ownership of a @pipe_buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer to attempt to steal
+ *
+ * Description:
+ * This function attempts to steal the @struct page attached to
+ * @buf. If successful, this function returns 0 and returns with
+ * the page locked. The caller may then reuse the page for whatever
+ * he wishes, the typical use is insertion into a different file
+ * page cache.
+ */
int generic_pipe_buf_steal(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct page *page = buf->page;
+ /*
+ * A reference of one is golden, that means that the owner of this
+ * page is the only one holding a reference to it. lock the page
+ * and return OK.
+ */
if (page_count(page) == 1) {
lock_page(page);
return 0;
return 1;
}
-void generic_pipe_buf_get(struct pipe_inode_info *info, struct pipe_buffer *buf)
+/**
+ * generic_pipe_buf_get - get a reference to a @struct pipe_buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer to get a reference to
+ *
+ * Description:
+ * This function grabs an extra reference to @buf. It's used in
+ * in the tee() system call, when we duplicate the buffers in one
+ * pipe into another.
+ */
+void generic_pipe_buf_get(struct pipe_inode_info *pipe, struct pipe_buffer *buf)
{
page_cache_get(buf->page);
}
-int generic_pipe_buf_pin(struct pipe_inode_info *info, struct pipe_buffer *buf)
+/**
+ * generic_pipe_buf_confirm - verify contents of the pipe buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer to confirm
+ *
+ * Description:
+ * This function does nothing, because the generic pipe code uses
+ * pages that are always good when inserted into the pipe.
+ */
+int generic_pipe_buf_confirm(struct pipe_inode_info *info,
+ struct pipe_buffer *buf)
{
return 0;
}
-static struct pipe_buf_operations anon_pipe_buf_ops = {
+static const struct pipe_buf_operations anon_pipe_buf_ops = {
.can_merge = 1,
.map = generic_pipe_buf_map,
.unmap = generic_pipe_buf_unmap,
- .pin = generic_pipe_buf_pin,
+ .confirm = generic_pipe_buf_confirm,
.release = anon_pipe_buf_release,
.steal = generic_pipe_buf_steal,
.get = generic_pipe_buf_get,
if (bufs) {
int curbuf = pipe->curbuf;
struct pipe_buffer *buf = pipe->bufs + curbuf;
- struct pipe_buf_operations *ops = buf->ops;
+ const struct pipe_buf_operations *ops = buf->ops;
void *addr;
size_t chars = buf->len;
int error, atomic;
if (chars > total_len)
chars = total_len;
- error = ops->pin(pipe, buf);
+ error = ops->confirm(pipe, buf);
if (error) {
if (!ret)
error = ret;
int lastbuf = (pipe->curbuf + pipe->nrbufs - 1) &
(PIPE_BUFFERS-1);
struct pipe_buffer *buf = pipe->bufs + lastbuf;
- struct pipe_buf_operations *ops = buf->ops;
+ const struct pipe_buf_operations *ops = buf->ops;
int offset = buf->offset + buf->len;
if (ops->can_merge && offset + chars <= PAGE_SIZE) {
int error, atomic = 1;
void *addr;
- error = ops->pin(pipe, buf);
+ error = ops->confirm(pipe, buf);
if (error)
goto out;
.fasync = pipe_rdwr_fasync,
};
-static struct file_operations read_pipe_fops = {
+static const struct file_operations read_pipe_fops = {
.llseek = no_llseek,
.read = do_sync_read,
.aio_read = pipe_read,
.fasync = pipe_read_fasync,
};
-static struct file_operations write_pipe_fops = {
+static const struct file_operations write_pipe_fops = {
.llseek = no_llseek,
.read = bad_pipe_r,
.write = do_sync_write,
.fasync = pipe_write_fasync,
};
-static struct file_operations rdwr_pipe_fops = {
+static const struct file_operations rdwr_pipe_fops = {
.llseek = no_llseek,
.read = do_sync_read,
.aio_read = pipe_read,
return 0;
}
+/*
+ * pipefs_dname() is called from d_path().
+ */
+static char *pipefs_dname(struct dentry *dentry, char *buffer, int buflen)
+{
+ return dynamic_dname(dentry, buffer, buflen, "pipe:[%lu]",
+ dentry->d_inode->i_ino);
+}
+
static struct dentry_operations pipefs_dentry_operations = {
.d_delete = pipefs_delete_dentry,
+ .d_dname = pipefs_dname,
};
static struct inode * get_pipe_inode(void)
struct inode *inode;
struct file *f;
struct dentry *dentry;
- char name[32];
- struct qstr this;
+ struct qstr name = { .name = "" };
f = get_empty_filp();
if (!f)
if (!inode)
goto err_file;
- this.len = sprintf(name, "[%lu]", inode->i_ino);
- this.name = name;
- this.hash = 0;
err = -ENOMEM;
- dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &this);
+ dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &name);
if (!dentry)
goto err_inode;
void free_write_pipe(struct file *f)
{
- mntput(f->f_path.mnt);
+ free_pipe_info(f->f_dentry->d_inode);
dput(f->f_path.dentry);
+ mntput(f->f_path.mnt);
put_filp(f);
}
goto err_fdr;
fdw = error;
+ error = audit_fd_pair(fdr, fdw);
+ if (error < 0)
+ goto err_fdw;
+
fd_install(fdr, fr);
fd_install(fdw, fw);
fd[0] = fdr;
return 0;
+ err_fdw:
+ put_unused_fd(fdw);
err_fdr:
put_unused_fd(fdr);
err_read_pipe:
+ dput(fr->f_dentry);
+ mntput(fr->f_vfsmnt);
put_filp(fr);
err_write_pipe:
free_write_pipe(fw);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff