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-rw-r--r--fs/pipe.c65
1 files changed, 40 insertions, 25 deletions
diff --git a/fs/pipe.c b/fs/pipe.c
index b1626f2..68090e8 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -207,7 +207,7 @@ int generic_pipe_buf_pin(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,
@@ -222,7 +222,7 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
unsigned long nr_segs, loff_t pos)
{
struct file *filp = iocb->ki_filp;
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
struct pipe_inode_info *pipe;
int do_wakeup;
ssize_t ret;
@@ -243,7 +243,7 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
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;
@@ -335,7 +335,7 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov,
unsigned long nr_segs, loff_t ppos)
{
struct file *filp = iocb->ki_filp;
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
struct pipe_inode_info *pipe;
ssize_t ret;
int do_wakeup;
@@ -365,7 +365,7 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov,
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) {
@@ -520,7 +520,7 @@ static int
pipe_ioctl(struct inode *pino, struct file *filp,
unsigned int cmd, unsigned long arg)
{
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
struct pipe_inode_info *pipe;
int count, buf, nrbufs;
@@ -548,7 +548,7 @@ static unsigned int
pipe_poll(struct file *filp, poll_table *wait)
{
unsigned int mask;
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
struct pipe_inode_info *pipe = inode->i_pipe;
int nrbufs;
@@ -601,7 +601,7 @@ pipe_release(struct inode *inode, int decr, int decw)
static int
pipe_read_fasync(int fd, struct file *filp, int on)
{
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
int retval;
mutex_lock(&inode->i_mutex);
@@ -618,7 +618,7 @@ pipe_read_fasync(int fd, struct file *filp, int on)
static int
pipe_write_fasync(int fd, struct file *filp, int on)
{
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
int retval;
mutex_lock(&inode->i_mutex);
@@ -635,7 +635,7 @@ pipe_write_fasync(int fd, struct file *filp, int on)
static int
pipe_rdwr_fasync(int fd, struct file *filp, int on)
{
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
struct pipe_inode_info *pipe = inode->i_pipe;
int retval;
@@ -756,7 +756,7 @@ const struct file_operations rdwr_fifo_fops = {
.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,
@@ -768,7 +768,7 @@ static struct file_operations read_pipe_fops = {
.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,
@@ -780,7 +780,7 @@ static struct file_operations write_pipe_fops = {
.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,
@@ -830,7 +830,14 @@ void free_pipe_info(struct inode *inode)
static struct vfsmount *pipe_mnt __read_mostly;
static int pipefs_delete_dentry(struct dentry *dentry)
{
- return 1;
+ /*
+ * At creation time, we pretended this dentry was hashed
+ * (by clearing DCACHE_UNHASHED bit in d_flags)
+ * At delete time, we restore the truth : not hashed.
+ * (so that dput() can proceed correctly)
+ */
+ dentry->d_flags |= DCACHE_UNHASHED;
+ return 0;
}
static struct dentry_operations pipefs_dentry_operations = {
@@ -891,19 +898,24 @@ struct file *create_write_pipe(void)
if (!inode)
goto err_file;
- sprintf(name, "[%lu]", inode->i_ino);
+ this.len = sprintf(name, "[%lu]", inode->i_ino);
this.name = name;
- this.len = strlen(name);
- this.hash = inode->i_ino; /* will go */
+ this.hash = 0;
err = -ENOMEM;
dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &this);
if (!dentry)
goto err_inode;
dentry->d_op = &pipefs_dentry_operations;
- d_add(dentry, inode);
- f->f_vfsmnt = mntget(pipe_mnt);
- f->f_dentry = dentry;
+ /*
+ * We dont want to publish this dentry into global dentry hash table.
+ * We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED
+ * This permits a working /proc/$pid/fd/XXX on pipes
+ */
+ dentry->d_flags &= ~DCACHE_UNHASHED;
+ d_instantiate(dentry, inode);
+ f->f_path.mnt = mntget(pipe_mnt);
+ f->f_path.dentry = dentry;
f->f_mapping = inode->i_mapping;
f->f_flags = O_WRONLY;
@@ -923,8 +935,9 @@ struct file *create_write_pipe(void)
void free_write_pipe(struct file *f)
{
- mntput(f->f_vfsmnt);
- dput(f->f_dentry);
+ free_pipe_info(f->f_dentry->d_inode);
+ dput(f->f_path.dentry);
+ mntput(f->f_path.mnt);
put_filp(f);
}
@@ -935,9 +948,9 @@ struct file *create_read_pipe(struct file *wrf)
return ERR_PTR(-ENFILE);
/* Grab pipe from the writer */
- f->f_vfsmnt = mntget(wrf->f_vfsmnt);
- f->f_dentry = dget(wrf->f_dentry);
- f->f_mapping = wrf->f_dentry->d_inode->i_mapping;
+ f->f_path.mnt = mntget(wrf->f_path.mnt);
+ f->f_path.dentry = dget(wrf->f_path.dentry);
+ f->f_mapping = wrf->f_path.dentry->d_inode->i_mapping;
f->f_pos = 0;
f->f_flags = O_RDONLY;
@@ -982,6 +995,8 @@ int do_pipe(int *fd)
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);
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