udf: limit the maximum number of indirect extents in a row

[pandora-kernel.git] / fs / pipe.c

diff --git a/fs/pipe.c b/fs/pipe.c
index 4065f07..d2cbeff 100644 (file)
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -103,25 +103,27 @@ void pipe_wait(struct pipe_inode_info *pipe)
 }
 
 static int
-pipe_iov_copy_from_user(void *to, struct iovec *iov, unsigned long len,
-                       int atomic)
+pipe_iov_copy_from_user(void *addr, int *offset, struct iovec *iov,
+                       size_t *remaining, int atomic)
 {
        unsigned long copy;
 
-       while (len > 0) {
+       while (*remaining > 0) {
                while (!iov->iov_len)
                        iov++;
-               copy = min_t(unsigned long, len, iov->iov_len);
+               copy = min_t(unsigned long, *remaining, iov->iov_len);
 
                if (atomic) {
-                       if (__copy_from_user_inatomic(to, iov->iov_base, copy))
+                       if (__copy_from_user_inatomic(addr + *offset,
+                                                     iov->iov_base, copy))
                                return -EFAULT;
                } else {
-                       if (copy_from_user(to, iov->iov_base, copy))
+                       if (copy_from_user(addr + *offset,
+                                          iov->iov_base, copy))
                                return -EFAULT;
                }
-               to += copy;
-               len -= copy;
+               *offset += copy;
+               *remaining -= copy;
                iov->iov_base += copy;
                iov->iov_len -= copy;
        }
@@ -129,25 +131,27 @@ pipe_iov_copy_from_user(void *to, struct iovec *iov, unsigned long len,
 }
 
 static int
-pipe_iov_copy_to_user(struct iovec *iov, const void *from, unsigned long len,
-                     int atomic)
+pipe_iov_copy_to_user(struct iovec *iov, void *addr, int *offset,
+                     size_t *remaining, int atomic)
 {
        unsigned long copy;
 
-       while (len > 0) {
+       while (*remaining > 0) {
                while (!iov->iov_len)
                        iov++;
-               copy = min_t(unsigned long, len, iov->iov_len);
+               copy = min_t(unsigned long, *remaining, iov->iov_len);
 
                if (atomic) {
-                       if (__copy_to_user_inatomic(iov->iov_base, from, copy))
+                       if (__copy_to_user_inatomic(iov->iov_base,
+                                                   addr + *offset, copy))
                                return -EFAULT;
                } else {
-                       if (copy_to_user(iov->iov_base, from, copy))
+                       if (copy_to_user(iov->iov_base,
+                                        addr + *offset, copy))
                                return -EFAULT;
                }
-               from += copy;
-               len -= copy;
+               *offset += copy;
+               *remaining -= copy;
                iov->iov_base += copy;
                iov->iov_len -= copy;
        }
@@ -345,6 +349,16 @@ static const struct pipe_buf_operations anon_pipe_buf_ops = {
        .get = generic_pipe_buf_get,
 };
 
+static const struct pipe_buf_operations packet_pipe_buf_ops = {
+       .can_merge = 0,
+       .map = generic_pipe_buf_map,
+       .unmap = generic_pipe_buf_unmap,
+       .confirm = generic_pipe_buf_confirm,
+       .release = anon_pipe_buf_release,
+       .steal = generic_pipe_buf_steal,
+       .get = generic_pipe_buf_get,
+};
+
 static ssize_t
 pipe_read(struct kiocb *iocb, const struct iovec *_iov,
           unsigned long nr_segs, loff_t pos)
@@ -373,7 +387,7 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
                        struct pipe_buffer *buf = pipe->bufs + curbuf;
                        const struct pipe_buf_operations *ops = buf->ops;
                        void *addr;
-                       size_t chars = buf->len;
+                       size_t chars = buf->len, remaining;
                        int error, atomic;
 
                        if (chars > total_len)
@@ -387,9 +401,11 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
                        }
 
                        atomic = !iov_fault_in_pages_write(iov, chars);
+                       remaining = chars;
 redo:
                        addr = ops->map(pipe, buf, atomic);
-                       error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars, atomic);
+                       error = pipe_iov_copy_to_user(iov, addr, &buf->offset,
+                                                     &remaining, atomic);
                        ops->unmap(pipe, buf, addr);
                        if (unlikely(error)) {
                                /*
@@ -404,8 +420,14 @@ redo:
                                break;
                        }
                        ret += chars;
-                       buf->offset += chars;
                        buf->len -= chars;
+
+                       /* Was it a packet buffer? Clean up and exit */
+                       if (buf->flags & PIPE_BUF_FLAG_PACKET) {
+                               total_len = chars;
+                               buf->len = 0;
+                       }
+
                        if (!buf->len) {
                                buf->ops = NULL;
                                ops->release(pipe, buf);
@@ -458,6 +480,11 @@ redo:
        return ret;
 }
 
+static inline int is_packetized(struct file *file)
+{
+       return (file->f_flags & O_DIRECT) != 0;
+}
+
 static ssize_t
 pipe_write(struct kiocb *iocb, const struct iovec *_iov,
            unsigned long nr_segs, loff_t ppos)
@@ -499,6 +526,7 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov,
                if (ops->can_merge && offset + chars <= PAGE_SIZE) {
                        int error, atomic = 1;
                        void *addr;
+                       size_t remaining = chars;
 
                        error = ops->confirm(pipe, buf);
                        if (error)
@@ -507,8 +535,8 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov,
                        iov_fault_in_pages_read(iov, chars);
 redo1:
                        addr = ops->map(pipe, buf, atomic);
-                       error = pipe_iov_copy_from_user(offset + addr, iov,
-                                                       chars, atomic);
+                       error = pipe_iov_copy_from_user(addr, &offset, iov,
+                                                       &remaining, atomic);
                        ops->unmap(pipe, buf, addr);
                        ret = error;
                        do_wakeup = 1;
@@ -543,6 +571,8 @@ redo1:
                        struct page *page = pipe->tmp_page;
                        char *src;
                        int error, atomic = 1;
+                       int offset = 0;
+                       size_t remaining;
 
                        if (!page) {
                                page = alloc_page(GFP_HIGHUSER);
@@ -563,14 +593,15 @@ redo1:
                                chars = total_len;
 
                        iov_fault_in_pages_read(iov, chars);
+                       remaining = chars;
 redo2:
                        if (atomic)
                                src = kmap_atomic(page, KM_USER0);
                        else
                                src = kmap(page);
 
-                       error = pipe_iov_copy_from_user(src, iov, chars,
-                                                       atomic);
+                       error = pipe_iov_copy_from_user(src, &offset, iov,
+                                                       &remaining, atomic);
                        if (atomic)
                                kunmap_atomic(src, KM_USER0);
                        else
@@ -592,6 +623,11 @@ redo2:
                        buf->ops = &anon_pipe_buf_ops;
                        buf->offset = 0;
                        buf->len = chars;
+                       buf->flags = 0;
+                       if (is_packetized(filp)) {
+                               buf->ops = &packet_pipe_buf_ops;
+                               buf->flags = PIPE_BUF_FLAG_PACKET;
+                       }
                        pipe->nrbufs = ++bufs;
                        pipe->tmp_page = NULL;
 
@@ -832,6 +868,9 @@ pipe_rdwr_open(struct inode *inode, struct file *filp)
 {
        int ret = -ENOENT;
 
+       if (!(filp->f_mode & (FMODE_READ|FMODE_WRITE)))
+               return -EINVAL;
+
        mutex_lock(&inode->i_mutex);
 
        if (inode->i_pipe) {
@@ -1012,7 +1051,7 @@ struct file *create_write_pipe(int flags)
                goto err_dentry;
        f->f_mapping = inode->i_mapping;
 
-       f->f_flags = O_WRONLY | (flags & O_NONBLOCK);
+       f->f_flags = O_WRONLY | (flags & (O_NONBLOCK | O_DIRECT));
        f->f_version = 0;
 
        return f;
@@ -1056,7 +1095,7 @@ int do_pipe_flags(int *fd, int flags)
        int error;
        int fdw, fdr;
 
-       if (flags & ~(O_CLOEXEC | O_NONBLOCK))
+       if (flags & ~(O_CLOEXEC | O_NONBLOCK | O_DIRECT))
                return -EINVAL;
 
        fw = create_write_pipe(flags);