[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/fs/read_write.c b/src/kernel/linux/v4.14/fs/read_write.c
new file mode 100644
index 0000000..0da6e4f
--- /dev/null
+++ b/src/kernel/linux/v4.14/fs/read_write.c
@@ -0,0 +1,2155 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/read_write.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#include <linux/slab.h>
+#include <linux/stat.h>
+#include <linux/sched/xacct.h>
+#include <linux/fcntl.h>
+#include <linux/file.h>
+#include <linux/uio.h>
+#include <linux/fsnotify.h>
+#include <linux/security.h>
+#include <linux/export.h>
+#include <linux/syscalls.h>
+#include <linux/pagemap.h>
+#include <linux/splice.h>
+#include <linux/compat.h>
+#include <linux/mount.h>
+#include <linux/fs.h>
+#include "internal.h"
+
+#include <linux/uaccess.h>
+#include <asm/unistd.h>
+
+const struct file_operations generic_ro_fops = {
+ .llseek = generic_file_llseek,
+ .read_iter = generic_file_read_iter,
+ .mmap = generic_file_readonly_mmap,
+ .splice_read = generic_file_splice_read,
+};
+
+EXPORT_SYMBOL(generic_ro_fops);
+
+static inline bool unsigned_offsets(struct file *file)
+{
+ return file->f_mode & FMODE_UNSIGNED_OFFSET;
+}
+
+/**
+ * vfs_setpos - update the file offset for lseek
+ * @file: file structure in question
+ * @offset: file offset to seek to
+ * @maxsize: maximum file size
+ *
+ * This is a low-level filesystem helper for updating the file offset to
+ * the value specified by @offset if the given offset is valid and it is
+ * not equal to the current file offset.
+ *
+ * Return the specified offset on success and -EINVAL on invalid offset.
+ */
+loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize)
+{
+ if (offset < 0 && !unsigned_offsets(file))
+ return -EINVAL;
+ if (offset > maxsize)
+ return -EINVAL;
+
+ if (offset != file->f_pos) {
+ file->f_pos = offset;
+ file->f_version = 0;
+ }
+ return offset;
+}
+EXPORT_SYMBOL(vfs_setpos);
+
+/**
+ * generic_file_llseek_size - generic llseek implementation for regular files
+ * @file: file structure to seek on
+ * @offset: file offset to seek to
+ * @whence: type of seek
+ * @size: max size of this file in file system
+ * @eof: offset used for SEEK_END position
+ *
+ * This is a variant of generic_file_llseek that allows passing in a custom
+ * maximum file size and a custom EOF position, for e.g. hashed directories
+ *
+ * Synchronization:
+ * SEEK_SET and SEEK_END are unsynchronized (but atomic on 64bit platforms)
+ * SEEK_CUR is synchronized against other SEEK_CURs, but not read/writes.
+ * read/writes behave like SEEK_SET against seeks.
+ */
+loff_t
+generic_file_llseek_size(struct file *file, loff_t offset, int whence,
+ loff_t maxsize, loff_t eof)
+{
+ switch (whence) {
+ case SEEK_END:
+ offset += eof;
+ break;
+ case SEEK_CUR:
+ /*
+ * Here we special-case the lseek(fd, 0, SEEK_CUR)
+ * position-querying operation. Avoid rewriting the "same"
+ * f_pos value back to the file because a concurrent read(),
+ * write() or lseek() might have altered it
+ */
+ if (offset == 0)
+ return file->f_pos;
+ /*
+ * f_lock protects against read/modify/write race with other
+ * SEEK_CURs. Note that parallel writes and reads behave
+ * like SEEK_SET.
+ */
+ spin_lock(&file->f_lock);
+ offset = vfs_setpos(file, file->f_pos + offset, maxsize);
+ spin_unlock(&file->f_lock);
+ return offset;
+ case SEEK_DATA:
+ /*
+ * In the generic case the entire file is data, so as long as
+ * offset isn't at the end of the file then the offset is data.
+ */
+ if ((unsigned long long)offset >= eof)
+ return -ENXIO;
+ break;
+ case SEEK_HOLE:
+ /*
+ * There is a virtual hole at the end of the file, so as long as
+ * offset isn't i_size or larger, return i_size.
+ */
+ if ((unsigned long long)offset >= eof)
+ return -ENXIO;
+ offset = eof;
+ break;
+ }
+
+ return vfs_setpos(file, offset, maxsize);
+}
+EXPORT_SYMBOL(generic_file_llseek_size);
+
+/**
+ * generic_file_llseek - generic llseek implementation for regular files
+ * @file: file structure to seek on
+ * @offset: file offset to seek to
+ * @whence: type of seek
+ *
+ * This is a generic implemenation of ->llseek useable for all normal local
+ * filesystems. It just updates the file offset to the value specified by
+ * @offset and @whence.
+ */
+loff_t generic_file_llseek(struct file *file, loff_t offset, int whence)
+{
+ struct inode *inode = file->f_mapping->host;
+
+ return generic_file_llseek_size(file, offset, whence,
+ inode->i_sb->s_maxbytes,
+ i_size_read(inode));
+}
+EXPORT_SYMBOL(generic_file_llseek);
+
+/**
+ * fixed_size_llseek - llseek implementation for fixed-sized devices
+ * @file: file structure to seek on
+ * @offset: file offset to seek to
+ * @whence: type of seek
+ * @size: size of the file
+ *
+ */
+loff_t fixed_size_llseek(struct file *file, loff_t offset, int whence, loff_t size)
+{
+ switch (whence) {
+ case SEEK_SET: case SEEK_CUR: case SEEK_END:
+ return generic_file_llseek_size(file, offset, whence,
+ size, size);
+ default:
+ return -EINVAL;
+ }
+}
+EXPORT_SYMBOL(fixed_size_llseek);
+
+/**
+ * no_seek_end_llseek - llseek implementation for fixed-sized devices
+ * @file: file structure to seek on
+ * @offset: file offset to seek to
+ * @whence: type of seek
+ *
+ */
+loff_t no_seek_end_llseek(struct file *file, loff_t offset, int whence)
+{
+ switch (whence) {
+ case SEEK_SET: case SEEK_CUR:
+ return generic_file_llseek_size(file, offset, whence,
+ OFFSET_MAX, 0);
+ default:
+ return -EINVAL;
+ }
+}
+EXPORT_SYMBOL(no_seek_end_llseek);
+
+/**
+ * no_seek_end_llseek_size - llseek implementation for fixed-sized devices
+ * @file: file structure to seek on
+ * @offset: file offset to seek to
+ * @whence: type of seek
+ * @size: maximal offset allowed
+ *
+ */
+loff_t no_seek_end_llseek_size(struct file *file, loff_t offset, int whence, loff_t size)
+{
+ switch (whence) {
+ case SEEK_SET: case SEEK_CUR:
+ return generic_file_llseek_size(file, offset, whence,
+ size, 0);
+ default:
+ return -EINVAL;
+ }
+}
+EXPORT_SYMBOL(no_seek_end_llseek_size);
+
+/**
+ * noop_llseek - No Operation Performed llseek implementation
+ * @file: file structure to seek on
+ * @offset: file offset to seek to
+ * @whence: type of seek
+ *
+ * This is an implementation of ->llseek useable for the rare special case when
+ * userspace expects the seek to succeed but the (device) file is actually not
+ * able to perform the seek. In this case you use noop_llseek() instead of
+ * falling back to the default implementation of ->llseek.
+ */
+loff_t noop_llseek(struct file *file, loff_t offset, int whence)
+{
+ return file->f_pos;
+}
+EXPORT_SYMBOL(noop_llseek);
+
+loff_t no_llseek(struct file *file, loff_t offset, int whence)
+{
+ return -ESPIPE;
+}
+EXPORT_SYMBOL(no_llseek);
+
+loff_t default_llseek(struct file *file, loff_t offset, int whence)
+{
+ struct inode *inode = file_inode(file);
+ loff_t retval;
+
+ inode_lock(inode);
+ switch (whence) {
+ case SEEK_END:
+ offset += i_size_read(inode);
+ break;
+ case SEEK_CUR:
+ if (offset == 0) {
+ retval = file->f_pos;
+ goto out;
+ }
+ offset += file->f_pos;
+ break;
+ case SEEK_DATA:
+ /*
+ * In the generic case the entire file is data, so as
+ * long as offset isn't at the end of the file then the
+ * offset is data.
+ */
+ if (offset >= inode->i_size) {
+ retval = -ENXIO;
+ goto out;
+ }
+ break;
+ case SEEK_HOLE:
+ /*
+ * There is a virtual hole at the end of the file, so
+ * as long as offset isn't i_size or larger, return
+ * i_size.
+ */
+ if (offset >= inode->i_size) {
+ retval = -ENXIO;
+ goto out;
+ }
+ offset = inode->i_size;
+ break;
+ }
+ retval = -EINVAL;
+ if (offset >= 0 || unsigned_offsets(file)) {
+ if (offset != file->f_pos) {
+ file->f_pos = offset;
+ file->f_version = 0;
+ }
+ retval = offset;
+ }
+out:
+ inode_unlock(inode);
+ return retval;
+}
+EXPORT_SYMBOL(default_llseek);
+
+loff_t vfs_llseek(struct file *file, loff_t offset, int whence)
+{
+ loff_t (*fn)(struct file *, loff_t, int);
+
+ fn = no_llseek;
+ if (file->f_mode & FMODE_LSEEK) {
+ if (file->f_op->llseek)
+ fn = file->f_op->llseek;
+ }
+ return fn(file, offset, whence);
+}
+EXPORT_SYMBOL(vfs_llseek);
+
+SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, whence)
+{
+ off_t retval;
+ struct fd f = fdget_pos(fd);
+ if (!f.file)
+ return -EBADF;
+
+ retval = -EINVAL;
+ if (whence <= SEEK_MAX) {
+ loff_t res = vfs_llseek(f.file, offset, whence);
+ retval = res;
+ if (res != (loff_t)retval)
+ retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */
+ }
+ fdput_pos(f);
+ return retval;
+}
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE3(lseek, unsigned int, fd, compat_off_t, offset, unsigned int, whence)
+{
+ return sys_lseek(fd, offset, whence);
+}
+#endif
+
+#ifdef __ARCH_WANT_SYS_LLSEEK
+SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high,
+ unsigned long, offset_low, loff_t __user *, result,
+ unsigned int, whence)
+{
+ int retval;
+ struct fd f = fdget_pos(fd);
+ loff_t offset;
+
+ if (!f.file)
+ return -EBADF;
+
+ retval = -EINVAL;
+ if (whence > SEEK_MAX)
+ goto out_putf;
+
+ offset = vfs_llseek(f.file, ((loff_t) offset_high << 32) | offset_low,
+ whence);
+
+ retval = (int)offset;
+ if (offset >= 0) {
+ retval = -EFAULT;
+ if (!copy_to_user(result, &offset, sizeof(offset)))
+ retval = 0;
+ }
+out_putf:
+ fdput_pos(f);
+ return retval;
+}
+#endif
+
+int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count)
+{
+ struct inode *inode;
+ loff_t pos;
+ int retval = -EINVAL;
+
+ inode = file_inode(file);
+ if (unlikely((ssize_t) count < 0))
+ return retval;
+ pos = *ppos;
+ if (unlikely(pos < 0)) {
+ if (!unsigned_offsets(file))
+ return retval;
+ if (count >= -pos) /* both values are in 0..LLONG_MAX */
+ return -EOVERFLOW;
+ } else if (unlikely((loff_t) (pos + count) < 0)) {
+ if (!unsigned_offsets(file))
+ return retval;
+ }
+
+ if (unlikely(inode->i_flctx && mandatory_lock(inode))) {
+ retval = locks_mandatory_area(inode, file, pos, pos + count - 1,
+ read_write == READ ? F_RDLCK : F_WRLCK);
+ if (retval < 0)
+ return retval;
+ }
+ return security_file_permission(file,
+ read_write == READ ? MAY_READ : MAY_WRITE);
+}
+
+static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
+{
+ struct iovec iov = { .iov_base = buf, .iov_len = len };
+ struct kiocb kiocb;
+ struct iov_iter iter;
+ ssize_t ret;
+
+ init_sync_kiocb(&kiocb, filp);
+ kiocb.ki_pos = *ppos;
+ iov_iter_init(&iter, READ, &iov, 1, len);
+
+ ret = call_read_iter(filp, &kiocb, &iter);
+ BUG_ON(ret == -EIOCBQUEUED);
+ *ppos = kiocb.ki_pos;
+ return ret;
+}
+
+ssize_t __vfs_read(struct file *file, char __user *buf, size_t count,
+ loff_t *pos)
+{
+ if (file->f_op->read)
+ return file->f_op->read(file, buf, count, pos);
+ else if (file->f_op->read_iter)
+ return new_sync_read(file, buf, count, pos);
+ else
+ return -EINVAL;
+}
+
+ssize_t kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
+{
+ mm_segment_t old_fs;
+ ssize_t result;
+
+ old_fs = get_fs();
+ set_fs(get_ds());
+ /* The cast to a user pointer is valid due to the set_fs() */
+ result = vfs_read(file, (void __user *)buf, count, pos);
+ set_fs(old_fs);
+ return result;
+}
+EXPORT_SYMBOL(kernel_read);
+
+ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
+{
+ ssize_t ret;
+
+ if (!(file->f_mode & FMODE_READ))
+ return -EBADF;
+ if (!(file->f_mode & FMODE_CAN_READ))
+ return -EINVAL;
+ if (unlikely(!access_ok(VERIFY_WRITE, buf, count)))
+ return -EFAULT;
+
+ ret = rw_verify_area(READ, file, pos, count);
+ if (!ret) {
+ if (count > MAX_RW_COUNT)
+ count = MAX_RW_COUNT;
+ ret = __vfs_read(file, buf, count, pos);
+ if (ret > 0) {
+ fsnotify_access(file);
+ add_rchar(current, ret);
+ }
+ inc_syscr(current);
+ }
+
+ return ret;
+}
+
+EXPORT_SYMBOL(vfs_read);
+
+static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
+{
+ struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
+ struct kiocb kiocb;
+ struct iov_iter iter;
+ ssize_t ret;
+
+ init_sync_kiocb(&kiocb, filp);
+ kiocb.ki_pos = *ppos;
+ iov_iter_init(&iter, WRITE, &iov, 1, len);
+
+ ret = call_write_iter(filp, &kiocb, &iter);
+ BUG_ON(ret == -EIOCBQUEUED);
+ if (ret > 0)
+ *ppos = kiocb.ki_pos;
+ return ret;
+}
+
+ssize_t __vfs_write(struct file *file, const char __user *p, size_t count,
+ loff_t *pos)
+{
+ if (file->f_op->write)
+ return file->f_op->write(file, p, count, pos);
+ else if (file->f_op->write_iter)
+ return new_sync_write(file, p, count, pos);
+ else
+ return -EINVAL;
+}
+
+ssize_t __kernel_write(struct file *file, const void *buf, size_t count, loff_t *pos)
+{
+ mm_segment_t old_fs;
+ const char __user *p;
+ ssize_t ret;
+
+ if (!(file->f_mode & FMODE_CAN_WRITE))
+ return -EINVAL;
+
+ old_fs = get_fs();
+ set_fs(get_ds());
+ p = (__force const char __user *)buf;
+ if (count > MAX_RW_COUNT)
+ count = MAX_RW_COUNT;
+ ret = __vfs_write(file, p, count, pos);
+ set_fs(old_fs);
+ if (ret > 0) {
+ fsnotify_modify(file);
+ add_wchar(current, ret);
+ }
+ inc_syscw(current);
+ return ret;
+}
+EXPORT_SYMBOL(__kernel_write);
+
+ssize_t kernel_write(struct file *file, const void *buf, size_t count,
+ loff_t *pos)
+{
+ mm_segment_t old_fs;
+ ssize_t res;
+
+ old_fs = get_fs();
+ set_fs(get_ds());
+ /* The cast to a user pointer is valid due to the set_fs() */
+ res = vfs_write(file, (__force const char __user *)buf, count, pos);
+ set_fs(old_fs);
+
+ return res;
+}
+EXPORT_SYMBOL(kernel_write);
+
+ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos)
+{
+ ssize_t ret;
+
+ if (!(file->f_mode & FMODE_WRITE))
+ return -EBADF;
+ if (!(file->f_mode & FMODE_CAN_WRITE))
+ return -EINVAL;
+ if (unlikely(!access_ok(VERIFY_READ, buf, count)))
+ return -EFAULT;
+
+ ret = rw_verify_area(WRITE, file, pos, count);
+ if (!ret) {
+ if (count > MAX_RW_COUNT)
+ count = MAX_RW_COUNT;
+ file_start_write(file);
+ ret = __vfs_write(file, buf, count, pos);
+ if (ret > 0) {
+ fsnotify_modify(file);
+ add_wchar(current, ret);
+ }
+ inc_syscw(current);
+ file_end_write(file);
+ }
+
+ return ret;
+}
+
+EXPORT_SYMBOL(vfs_write);
+
+static inline loff_t file_pos_read(struct file *file)
+{
+ return file->f_mode & FMODE_STREAM ? 0 : file->f_pos;
+}
+
+static inline void file_pos_write(struct file *file, loff_t pos)
+{
+ if ((file->f_mode & FMODE_STREAM) == 0)
+ file->f_pos = pos;
+}
+
+SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)
+{
+ struct fd f = fdget_pos(fd);
+ ssize_t ret = -EBADF;
+
+ if (f.file) {
+ loff_t pos = file_pos_read(f.file);
+ ret = vfs_read(f.file, buf, count, &pos);
+ if (ret >= 0)
+ file_pos_write(f.file, pos);
+ fdput_pos(f);
+ }
+ return ret;
+}
+
+SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf,
+ size_t, count)
+{
+ struct fd f = fdget_pos(fd);
+ ssize_t ret = -EBADF;
+
+ if (f.file) {
+ loff_t pos = file_pos_read(f.file);
+ ret = vfs_write(f.file, buf, count, &pos);
+ if (ret >= 0)
+ file_pos_write(f.file, pos);
+ fdput_pos(f);
+ }
+
+ return ret;
+}
+
+SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf,
+ size_t, count, loff_t, pos)
+{
+ struct fd f;
+ ssize_t ret = -EBADF;
+
+ if (pos < 0)
+ return -EINVAL;
+
+ f = fdget(fd);
+ if (f.file) {
+ ret = -ESPIPE;
+ if (f.file->f_mode & FMODE_PREAD)
+ ret = vfs_read(f.file, buf, count, &pos);
+ fdput(f);
+ }
+
+ return ret;
+}
+
+SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf,
+ size_t, count, loff_t, pos)
+{
+ struct fd f;
+ ssize_t ret = -EBADF;
+
+ if (pos < 0)
+ return -EINVAL;
+
+ f = fdget(fd);
+ if (f.file) {
+ ret = -ESPIPE;
+ if (f.file->f_mode & FMODE_PWRITE)
+ ret = vfs_write(f.file, buf, count, &pos);
+ fdput(f);
+ }
+
+ return ret;
+}
+
+/*
+ * Reduce an iovec's length in-place. Return the resulting number of segments
+ */
+unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to)
+{
+ unsigned long seg = 0;
+ size_t len = 0;
+
+ while (seg < nr_segs) {
+ seg++;
+ if (len + iov->iov_len >= to) {
+ iov->iov_len = to - len;
+ break;
+ }
+ len += iov->iov_len;
+ iov++;
+ }
+ return seg;
+}
+EXPORT_SYMBOL(iov_shorten);
+
+static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter,
+ loff_t *ppos, int type, rwf_t flags)
+{
+ struct kiocb kiocb;
+ ssize_t ret;
+
+ init_sync_kiocb(&kiocb, filp);
+ ret = kiocb_set_rw_flags(&kiocb, flags);
+ if (ret)
+ return ret;
+ kiocb.ki_pos = *ppos;
+
+ if (type == READ)
+ ret = call_read_iter(filp, &kiocb, iter);
+ else
+ ret = call_write_iter(filp, &kiocb, iter);
+ BUG_ON(ret == -EIOCBQUEUED);
+ *ppos = kiocb.ki_pos;
+ return ret;
+}
+
+/* Do it by hand, with file-ops */
+static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter,
+ loff_t *ppos, int type, rwf_t flags)
+{
+ ssize_t ret = 0;
+
+ if (flags & ~RWF_HIPRI)
+ return -EOPNOTSUPP;
+
+ while (iov_iter_count(iter)) {
+ struct iovec iovec = iov_iter_iovec(iter);
+ ssize_t nr;
+
+ if (type == READ) {
+ nr = filp->f_op->read(filp, iovec.iov_base,
+ iovec.iov_len, ppos);
+ } else {
+ nr = filp->f_op->write(filp, iovec.iov_base,
+ iovec.iov_len, ppos);
+ }
+
+ if (nr < 0) {
+ if (!ret)
+ ret = nr;
+ break;
+ }
+ ret += nr;
+ if (nr != iovec.iov_len)
+ break;
+ iov_iter_advance(iter, nr);
+ }
+
+ return ret;
+}
+
+/* A write operation does a read from user space and vice versa */
+#define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ)
+
+/**
+ * rw_copy_check_uvector() - Copy an array of &struct iovec from userspace
+ * into the kernel and check that it is valid.
+ *
+ * @type: One of %CHECK_IOVEC_ONLY, %READ, or %WRITE.
+ * @uvector: Pointer to the userspace array.
+ * @nr_segs: Number of elements in userspace array.
+ * @fast_segs: Number of elements in @fast_pointer.
+ * @fast_pointer: Pointer to (usually small on-stack) kernel array.
+ * @ret_pointer: (output parameter) Pointer to a variable that will point to
+ * either @fast_pointer, a newly allocated kernel array, or NULL,
+ * depending on which array was used.
+ *
+ * This function copies an array of &struct iovec of @nr_segs from
+ * userspace into the kernel and checks that each element is valid (e.g.
+ * it does not point to a kernel address or cause overflow by being too
+ * large, etc.).
+ *
+ * As an optimization, the caller may provide a pointer to a small
+ * on-stack array in @fast_pointer, typically %UIO_FASTIOV elements long
+ * (the size of this array, or 0 if unused, should be given in @fast_segs).
+ *
+ * @ret_pointer will always point to the array that was used, so the
+ * caller must take care not to call kfree() on it e.g. in case the
+ * @fast_pointer array was used and it was allocated on the stack.
+ *
+ * Return: The total number of bytes covered by the iovec array on success
+ * or a negative error code on error.
+ */
+ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
+ unsigned long nr_segs, unsigned long fast_segs,
+ struct iovec *fast_pointer,
+ struct iovec **ret_pointer)
+{
+ unsigned long seg;
+ ssize_t ret;
+ struct iovec *iov = fast_pointer;
+
+ /*
+ * SuS says "The readv() function *may* fail if the iovcnt argument
+ * was less than or equal to 0, or greater than {IOV_MAX}. Linux has
+ * traditionally returned zero for zero segments, so...
+ */
+ if (nr_segs == 0) {
+ ret = 0;
+ goto out;
+ }
+
+ /*
+ * First get the "struct iovec" from user memory and
+ * verify all the pointers
+ */
+ if (nr_segs > UIO_MAXIOV) {
+ ret = -EINVAL;
+ goto out;
+ }
+ if (nr_segs > fast_segs) {
+ iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);
+ if (iov == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ }
+ if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ /*
+ * According to the Single Unix Specification we should return EINVAL
+ * if an element length is < 0 when cast to ssize_t or if the
+ * total length would overflow the ssize_t return value of the
+ * system call.
+ *
+ * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the
+ * overflow case.
+ */
+ ret = 0;
+ for (seg = 0; seg < nr_segs; seg++) {
+ void __user *buf = iov[seg].iov_base;
+ ssize_t len = (ssize_t)iov[seg].iov_len;
+
+ /* see if we we're about to use an invalid len or if
+ * it's about to overflow ssize_t */
+ if (len < 0) {
+ ret = -EINVAL;
+ goto out;
+ }
+ if (type >= 0
+ && unlikely(!access_ok(vrfy_dir(type), buf, len))) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (len > MAX_RW_COUNT - ret) {
+ len = MAX_RW_COUNT - ret;
+ iov[seg].iov_len = len;
+ }
+ ret += len;
+ }
+out:
+ *ret_pointer = iov;
+ return ret;
+}
+
+#ifdef CONFIG_COMPAT
+ssize_t compat_rw_copy_check_uvector(int type,
+ const struct compat_iovec __user *uvector, unsigned long nr_segs,
+ unsigned long fast_segs, struct iovec *fast_pointer,
+ struct iovec **ret_pointer)
+{
+ compat_ssize_t tot_len;
+ struct iovec *iov = *ret_pointer = fast_pointer;
+ ssize_t ret = 0;
+ int seg;
+
+ /*
+ * SuS says "The readv() function *may* fail if the iovcnt argument
+ * was less than or equal to 0, or greater than {IOV_MAX}. Linux has
+ * traditionally returned zero for zero segments, so...
+ */
+ if (nr_segs == 0)
+ goto out;
+
+ ret = -EINVAL;
+ if (nr_segs > UIO_MAXIOV)
+ goto out;
+ if (nr_segs > fast_segs) {
+ ret = -ENOMEM;
+ iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);
+ if (iov == NULL)
+ goto out;
+ }
+ *ret_pointer = iov;
+
+ ret = -EFAULT;
+ if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector)))
+ goto out;
+
+ /*
+ * Single unix specification:
+ * We should -EINVAL if an element length is not >= 0 and fitting an
+ * ssize_t.
+ *
+ * In Linux, the total length is limited to MAX_RW_COUNT, there is
+ * no overflow possibility.
+ */
+ tot_len = 0;
+ ret = -EINVAL;
+ for (seg = 0; seg < nr_segs; seg++) {
+ compat_uptr_t buf;
+ compat_ssize_t len;
+
+ if (__get_user(len, &uvector->iov_len) ||
+ __get_user(buf, &uvector->iov_base)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (len < 0) /* size_t not fitting in compat_ssize_t .. */
+ goto out;
+ if (type >= 0 &&
+ !access_ok(vrfy_dir(type), compat_ptr(buf), len)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (len > MAX_RW_COUNT - tot_len)
+ len = MAX_RW_COUNT - tot_len;
+ tot_len += len;
+ iov->iov_base = compat_ptr(buf);
+ iov->iov_len = (compat_size_t) len;
+ uvector++;
+ iov++;
+ }
+ ret = tot_len;
+
+out:
+ return ret;
+}
+#endif
+
+static ssize_t do_iter_read(struct file *file, struct iov_iter *iter,
+ loff_t *pos, rwf_t flags)
+{
+ size_t tot_len;
+ ssize_t ret = 0;
+
+ if (!(file->f_mode & FMODE_READ))
+ return -EBADF;
+ if (!(file->f_mode & FMODE_CAN_READ))
+ return -EINVAL;
+
+ tot_len = iov_iter_count(iter);
+ if (!tot_len)
+ goto out;
+ ret = rw_verify_area(READ, file, pos, tot_len);
+ if (ret < 0)
+ return ret;
+
+ if (file->f_op->read_iter)
+ ret = do_iter_readv_writev(file, iter, pos, READ, flags);
+ else
+ ret = do_loop_readv_writev(file, iter, pos, READ, flags);
+out:
+ if (ret >= 0)
+ fsnotify_access(file);
+ return ret;
+}
+
+ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos,
+ rwf_t flags)
+{
+ if (!file->f_op->read_iter)
+ return -EINVAL;
+ return do_iter_read(file, iter, ppos, flags);
+}
+EXPORT_SYMBOL(vfs_iter_read);
+
+static ssize_t do_iter_write(struct file *file, struct iov_iter *iter,
+ loff_t *pos, rwf_t flags)
+{
+ size_t tot_len;
+ ssize_t ret = 0;
+
+ if (!(file->f_mode & FMODE_WRITE))
+ return -EBADF;
+ if (!(file->f_mode & FMODE_CAN_WRITE))
+ return -EINVAL;
+
+ tot_len = iov_iter_count(iter);
+ if (!tot_len)
+ return 0;
+ ret = rw_verify_area(WRITE, file, pos, tot_len);
+ if (ret < 0)
+ return ret;
+
+ if (file->f_op->write_iter)
+ ret = do_iter_readv_writev(file, iter, pos, WRITE, flags);
+ else
+ ret = do_loop_readv_writev(file, iter, pos, WRITE, flags);
+ if (ret > 0)
+ fsnotify_modify(file);
+ return ret;
+}
+
+ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos,
+ rwf_t flags)
+{
+ if (!file->f_op->write_iter)
+ return -EINVAL;
+ return do_iter_write(file, iter, ppos, flags);
+}
+EXPORT_SYMBOL(vfs_iter_write);
+
+ssize_t vfs_readv(struct file *file, const struct iovec __user *vec,
+ unsigned long vlen, loff_t *pos, rwf_t flags)
+{
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ struct iov_iter iter;
+ ssize_t ret;
+
+ ret = import_iovec(READ, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
+ if (ret >= 0) {
+ ret = do_iter_read(file, &iter, pos, flags);
+ kfree(iov);
+ }
+
+ return ret;
+}
+
+static ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
+ unsigned long vlen, loff_t *pos, rwf_t flags)
+{
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ struct iov_iter iter;
+ ssize_t ret;
+
+ ret = import_iovec(WRITE, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
+ if (ret >= 0) {
+ file_start_write(file);
+ ret = do_iter_write(file, &iter, pos, flags);
+ file_end_write(file);
+ kfree(iov);
+ }
+ return ret;
+}
+
+static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec,
+ unsigned long vlen, rwf_t flags)
+{
+ struct fd f = fdget_pos(fd);
+ ssize_t ret = -EBADF;
+
+ if (f.file) {
+ loff_t pos = file_pos_read(f.file);
+ ret = vfs_readv(f.file, vec, vlen, &pos, flags);
+ if (ret >= 0)
+ file_pos_write(f.file, pos);
+ fdput_pos(f);
+ }
+
+ if (ret > 0)
+ add_rchar(current, ret);
+ inc_syscr(current);
+ return ret;
+}
+
+static ssize_t do_writev(unsigned long fd, const struct iovec __user *vec,
+ unsigned long vlen, rwf_t flags)
+{
+ struct fd f = fdget_pos(fd);
+ ssize_t ret = -EBADF;
+
+ if (f.file) {
+ loff_t pos = file_pos_read(f.file);
+ ret = vfs_writev(f.file, vec, vlen, &pos, flags);
+ if (ret >= 0)
+ file_pos_write(f.file, pos);
+ fdput_pos(f);
+ }
+
+ if (ret > 0)
+ add_wchar(current, ret);
+ inc_syscw(current);
+ return ret;
+}
+
+static inline loff_t pos_from_hilo(unsigned long high, unsigned long low)
+{
+#define HALF_LONG_BITS (BITS_PER_LONG / 2)
+ return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low;
+}
+
+static ssize_t do_preadv(unsigned long fd, const struct iovec __user *vec,
+ unsigned long vlen, loff_t pos, rwf_t flags)
+{
+ struct fd f;
+ ssize_t ret = -EBADF;
+
+ if (pos < 0)
+ return -EINVAL;
+
+ f = fdget(fd);
+ if (f.file) {
+ ret = -ESPIPE;
+ if (f.file->f_mode & FMODE_PREAD)
+ ret = vfs_readv(f.file, vec, vlen, &pos, flags);
+ fdput(f);
+ }
+
+ if (ret > 0)
+ add_rchar(current, ret);
+ inc_syscr(current);
+ return ret;
+}
+
+static ssize_t do_pwritev(unsigned long fd, const struct iovec __user *vec,
+ unsigned long vlen, loff_t pos, rwf_t flags)
+{
+ struct fd f;
+ ssize_t ret = -EBADF;
+
+ if (pos < 0)
+ return -EINVAL;
+
+ f = fdget(fd);
+ if (f.file) {
+ ret = -ESPIPE;
+ if (f.file->f_mode & FMODE_PWRITE)
+ ret = vfs_writev(f.file, vec, vlen, &pos, flags);
+ fdput(f);
+ }
+
+ if (ret > 0)
+ add_wchar(current, ret);
+ inc_syscw(current);
+ return ret;
+}
+
+SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen)
+{
+ return do_readv(fd, vec, vlen, 0);
+}
+
+SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen)
+{
+ return do_writev(fd, vec, vlen, 0);
+}
+
+SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h)
+{
+ loff_t pos = pos_from_hilo(pos_h, pos_l);
+
+ return do_preadv(fd, vec, vlen, pos, 0);
+}
+
+SYSCALL_DEFINE6(preadv2, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h,
+ rwf_t, flags)
+{
+ loff_t pos = pos_from_hilo(pos_h, pos_l);
+
+ if (pos == -1)
+ return do_readv(fd, vec, vlen, flags);
+
+ return do_preadv(fd, vec, vlen, pos, flags);
+}
+
+SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h)
+{
+ loff_t pos = pos_from_hilo(pos_h, pos_l);
+
+ return do_pwritev(fd, vec, vlen, pos, 0);
+}
+
+SYSCALL_DEFINE6(pwritev2, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h,
+ rwf_t, flags)
+{
+ loff_t pos = pos_from_hilo(pos_h, pos_l);
+
+ if (pos == -1)
+ return do_writev(fd, vec, vlen, flags);
+
+ return do_pwritev(fd, vec, vlen, pos, flags);
+}
+
+#ifdef CONFIG_COMPAT
+static size_t compat_readv(struct file *file,
+ const struct compat_iovec __user *vec,
+ unsigned long vlen, loff_t *pos, rwf_t flags)
+{
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ struct iov_iter iter;
+ ssize_t ret;
+
+ ret = compat_import_iovec(READ, vec, vlen, UIO_FASTIOV, &iov, &iter);
+ if (ret >= 0) {
+ ret = do_iter_read(file, &iter, pos, flags);
+ kfree(iov);
+ }
+ if (ret > 0)
+ add_rchar(current, ret);
+ inc_syscr(current);
+ return ret;
+}
+
+static size_t do_compat_readv(compat_ulong_t fd,
+ const struct compat_iovec __user *vec,
+ compat_ulong_t vlen, rwf_t flags)
+{
+ struct fd f = fdget_pos(fd);
+ ssize_t ret;
+ loff_t pos;
+
+ if (!f.file)
+ return -EBADF;
+ pos = f.file->f_pos;
+ ret = compat_readv(f.file, vec, vlen, &pos, flags);
+ if (ret >= 0)
+ f.file->f_pos = pos;
+ fdput_pos(f);
+ return ret;
+
+}
+
+COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd,
+ const struct compat_iovec __user *,vec,
+ compat_ulong_t, vlen)
+{
+ return do_compat_readv(fd, vec, vlen, 0);
+}
+
+static long do_compat_preadv64(unsigned long fd,
+ const struct compat_iovec __user *vec,
+ unsigned long vlen, loff_t pos, rwf_t flags)
+{
+ struct fd f;
+ ssize_t ret;
+
+ if (pos < 0)
+ return -EINVAL;
+ f = fdget(fd);
+ if (!f.file)
+ return -EBADF;
+ ret = -ESPIPE;
+ if (f.file->f_mode & FMODE_PREAD)
+ ret = compat_readv(f.file, vec, vlen, &pos, flags);
+ fdput(f);
+ return ret;
+}
+
+#ifdef __ARCH_WANT_COMPAT_SYS_PREADV64
+COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd,
+ const struct compat_iovec __user *,vec,
+ unsigned long, vlen, loff_t, pos)
+{
+ return do_compat_preadv64(fd, vec, vlen, pos, 0);
+}
+#endif
+
+COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd,
+ const struct compat_iovec __user *,vec,
+ compat_ulong_t, vlen, u32, pos_low, u32, pos_high)
+{
+ loff_t pos = ((loff_t)pos_high << 32) | pos_low;
+
+ return do_compat_preadv64(fd, vec, vlen, pos, 0);
+}
+
+#ifdef __ARCH_WANT_COMPAT_SYS_PREADV64V2
+COMPAT_SYSCALL_DEFINE5(preadv64v2, unsigned long, fd,
+ const struct compat_iovec __user *,vec,
+ unsigned long, vlen, loff_t, pos, rwf_t, flags)
+{
+ if (pos == -1)
+ return do_compat_readv(fd, vec, vlen, flags);
+
+ return do_compat_preadv64(fd, vec, vlen, pos, flags);
+}
+#endif
+
+COMPAT_SYSCALL_DEFINE6(preadv2, compat_ulong_t, fd,
+ const struct compat_iovec __user *,vec,
+ compat_ulong_t, vlen, u32, pos_low, u32, pos_high,
+ rwf_t, flags)
+{
+ loff_t pos = ((loff_t)pos_high << 32) | pos_low;
+
+ if (pos == -1)
+ return do_compat_readv(fd, vec, vlen, flags);
+
+ return do_compat_preadv64(fd, vec, vlen, pos, flags);
+}
+
+static size_t compat_writev(struct file *file,
+ const struct compat_iovec __user *vec,
+ unsigned long vlen, loff_t *pos, rwf_t flags)
+{
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ struct iov_iter iter;
+ ssize_t ret;
+
+ ret = compat_import_iovec(WRITE, vec, vlen, UIO_FASTIOV, &iov, &iter);
+ if (ret >= 0) {
+ file_start_write(file);
+ ret = do_iter_write(file, &iter, pos, flags);
+ file_end_write(file);
+ kfree(iov);
+ }
+ if (ret > 0)
+ add_wchar(current, ret);
+ inc_syscw(current);
+ return ret;
+}
+
+static size_t do_compat_writev(compat_ulong_t fd,
+ const struct compat_iovec __user* vec,
+ compat_ulong_t vlen, rwf_t flags)
+{
+ struct fd f = fdget_pos(fd);
+ ssize_t ret;
+ loff_t pos;
+
+ if (!f.file)
+ return -EBADF;
+ pos = f.file->f_pos;
+ ret = compat_writev(f.file, vec, vlen, &pos, flags);
+ if (ret >= 0)
+ f.file->f_pos = pos;
+ fdput_pos(f);
+ return ret;
+}
+
+COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd,
+ const struct compat_iovec __user *, vec,
+ compat_ulong_t, vlen)
+{
+ return do_compat_writev(fd, vec, vlen, 0);
+}
+
+static long do_compat_pwritev64(unsigned long fd,
+ const struct compat_iovec __user *vec,
+ unsigned long vlen, loff_t pos, rwf_t flags)
+{
+ struct fd f;
+ ssize_t ret;
+
+ if (pos < 0)
+ return -EINVAL;
+ f = fdget(fd);
+ if (!f.file)
+ return -EBADF;
+ ret = -ESPIPE;
+ if (f.file->f_mode & FMODE_PWRITE)
+ ret = compat_writev(f.file, vec, vlen, &pos, flags);
+ fdput(f);
+ return ret;
+}
+
+#ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64
+COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd,
+ const struct compat_iovec __user *,vec,
+ unsigned long, vlen, loff_t, pos)
+{
+ return do_compat_pwritev64(fd, vec, vlen, pos, 0);
+}
+#endif
+
+COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd,
+ const struct compat_iovec __user *,vec,
+ compat_ulong_t, vlen, u32, pos_low, u32, pos_high)
+{
+ loff_t pos = ((loff_t)pos_high << 32) | pos_low;
+
+ return do_compat_pwritev64(fd, vec, vlen, pos, 0);
+}
+
+#ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64V2
+COMPAT_SYSCALL_DEFINE5(pwritev64v2, unsigned long, fd,
+ const struct compat_iovec __user *,vec,
+ unsigned long, vlen, loff_t, pos, rwf_t, flags)
+{
+ if (pos == -1)
+ return do_compat_writev(fd, vec, vlen, flags);
+
+ return do_compat_pwritev64(fd, vec, vlen, pos, flags);
+}
+#endif
+
+COMPAT_SYSCALL_DEFINE6(pwritev2, compat_ulong_t, fd,
+ const struct compat_iovec __user *,vec,
+ compat_ulong_t, vlen, u32, pos_low, u32, pos_high, rwf_t, flags)
+{
+ loff_t pos = ((loff_t)pos_high << 32) | pos_low;
+
+ if (pos == -1)
+ return do_compat_writev(fd, vec, vlen, flags);
+
+ return do_compat_pwritev64(fd, vec, vlen, pos, flags);
+}
+
+#endif
+
+static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
+ size_t count, loff_t max)
+{
+ struct fd in, out;
+ struct inode *in_inode, *out_inode;
+ loff_t pos;
+ loff_t out_pos;
+ ssize_t retval;
+ int fl;
+
+ /*
+ * Get input file, and verify that it is ok..
+ */
+ retval = -EBADF;
+ in = fdget(in_fd);
+ if (!in.file)
+ goto out;
+ if (!(in.file->f_mode & FMODE_READ))
+ goto fput_in;
+ retval = -ESPIPE;
+ if (!ppos) {
+ pos = in.file->f_pos;
+ } else {
+ pos = *ppos;
+ if (!(in.file->f_mode & FMODE_PREAD))
+ goto fput_in;
+ }
+ retval = rw_verify_area(READ, in.file, &pos, count);
+ if (retval < 0)
+ goto fput_in;
+ if (count > MAX_RW_COUNT)
+ count = MAX_RW_COUNT;
+
+ /*
+ * Get output file, and verify that it is ok..
+ */
+ retval = -EBADF;
+ out = fdget(out_fd);
+ if (!out.file)
+ goto fput_in;
+ if (!(out.file->f_mode & FMODE_WRITE))
+ goto fput_out;
+ retval = -EINVAL;
+ in_inode = file_inode(in.file);
+ out_inode = file_inode(out.file);
+ out_pos = out.file->f_pos;
+ retval = rw_verify_area(WRITE, out.file, &out_pos, count);
+ if (retval < 0)
+ goto fput_out;
+
+ if (!max)
+ max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);
+
+ if (unlikely(pos + count > max)) {
+ retval = -EOVERFLOW;
+ if (pos >= max)
+ goto fput_out;
+ count = max - pos;
+ }
+
+ fl = 0;
+#if 0
+ /*
+ * We need to debate whether we can enable this or not. The
+ * man page documents EAGAIN return for the output at least,
+ * and the application is arguably buggy if it doesn't expect
+ * EAGAIN on a non-blocking file descriptor.
+ */
+ if (in.file->f_flags & O_NONBLOCK)
+ fl = SPLICE_F_NONBLOCK;
+#endif
+ file_start_write(out.file);
+ retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl);
+ file_end_write(out.file);
+
+ if (retval > 0) {
+ add_rchar(current, retval);
+ add_wchar(current, retval);
+ fsnotify_access(in.file);
+ fsnotify_modify(out.file);
+ out.file->f_pos = out_pos;
+ if (ppos)
+ *ppos = pos;
+ else
+ in.file->f_pos = pos;
+ }
+
+ inc_syscr(current);
+ inc_syscw(current);
+ if (pos > max)
+ retval = -EOVERFLOW;
+
+fput_out:
+ fdput(out);
+fput_in:
+ fdput(in);
+out:
+ return retval;
+}
+
+SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count)
+{
+ loff_t pos;
+ off_t off;
+ ssize_t ret;
+
+ if (offset) {
+ if (unlikely(get_user(off, offset)))
+ return -EFAULT;
+ pos = off;
+ ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
+ if (unlikely(put_user(pos, offset)))
+ return -EFAULT;
+ return ret;
+ }
+
+ return do_sendfile(out_fd, in_fd, NULL, count, 0);
+}
+
+SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count)
+{
+ loff_t pos;
+ ssize_t ret;
+
+ if (offset) {
+ if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
+ return -EFAULT;
+ ret = do_sendfile(out_fd, in_fd, &pos, count, 0);
+ if (unlikely(put_user(pos, offset)))
+ return -EFAULT;
+ return ret;
+ }
+
+ return do_sendfile(out_fd, in_fd, NULL, count, 0);
+}
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd,
+ compat_off_t __user *, offset, compat_size_t, count)
+{
+ loff_t pos;
+ off_t off;
+ ssize_t ret;
+
+ if (offset) {
+ if (unlikely(get_user(off, offset)))
+ return -EFAULT;
+ pos = off;
+ ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
+ if (unlikely(put_user(pos, offset)))
+ return -EFAULT;
+ return ret;
+ }
+
+ return do_sendfile(out_fd, in_fd, NULL, count, 0);
+}
+
+COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd,
+ compat_loff_t __user *, offset, compat_size_t, count)
+{
+ loff_t pos;
+ ssize_t ret;
+
+ if (offset) {
+ if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
+ return -EFAULT;
+ ret = do_sendfile(out_fd, in_fd, &pos, count, 0);
+ if (unlikely(put_user(pos, offset)))
+ return -EFAULT;
+ return ret;
+ }
+
+ return do_sendfile(out_fd, in_fd, NULL, count, 0);
+}
+#endif
+
+/*
+ * copy_file_range() differs from regular file read and write in that it
+ * specifically allows return partial success. When it does so is up to
+ * the copy_file_range method.
+ */
+ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ size_t len, unsigned int flags)
+{
+ struct inode *inode_in = file_inode(file_in);
+ struct inode *inode_out = file_inode(file_out);
+ ssize_t ret;
+
+ if (flags != 0)
+ return -EINVAL;
+
+ if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
+ return -EISDIR;
+ if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
+ return -EINVAL;
+
+ ret = rw_verify_area(READ, file_in, &pos_in, len);
+ if (unlikely(ret))
+ return ret;
+
+ ret = rw_verify_area(WRITE, file_out, &pos_out, len);
+ if (unlikely(ret))
+ return ret;
+
+ if (!(file_in->f_mode & FMODE_READ) ||
+ !(file_out->f_mode & FMODE_WRITE) ||
+ (file_out->f_flags & O_APPEND))
+ return -EBADF;
+
+ /* this could be relaxed once a method supports cross-fs copies */
+ if (inode_in->i_sb != inode_out->i_sb)
+ return -EXDEV;
+
+ if (len == 0)
+ return 0;
+
+ file_start_write(file_out);
+
+ /*
+ * Try cloning first, this is supported by more file systems, and
+ * more efficient if both clone and copy are supported (e.g. NFS).
+ */
+ if (file_in->f_op->clone_file_range) {
+ ret = file_in->f_op->clone_file_range(file_in, pos_in,
+ file_out, pos_out, len);
+ if (ret == 0) {
+ ret = len;
+ goto done;
+ }
+ }
+
+ if (file_out->f_op->copy_file_range) {
+ ret = file_out->f_op->copy_file_range(file_in, pos_in, file_out,
+ pos_out, len, flags);
+ if (ret != -EOPNOTSUPP)
+ goto done;
+ }
+
+ ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out,
+ len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0);
+
+done:
+ if (ret > 0) {
+ fsnotify_access(file_in);
+ add_rchar(current, ret);
+ fsnotify_modify(file_out);
+ add_wchar(current, ret);
+ }
+
+ inc_syscr(current);
+ inc_syscw(current);
+
+ file_end_write(file_out);
+
+ return ret;
+}
+EXPORT_SYMBOL(vfs_copy_file_range);
+
+SYSCALL_DEFINE6(copy_file_range, int, fd_in, loff_t __user *, off_in,
+ int, fd_out, loff_t __user *, off_out,
+ size_t, len, unsigned int, flags)
+{
+ loff_t pos_in;
+ loff_t pos_out;
+ struct fd f_in;
+ struct fd f_out;
+ ssize_t ret = -EBADF;
+
+ f_in = fdget(fd_in);
+ if (!f_in.file)
+ goto out2;
+
+ f_out = fdget(fd_out);
+ if (!f_out.file)
+ goto out1;
+
+ ret = -EFAULT;
+ if (off_in) {
+ if (copy_from_user(&pos_in, off_in, sizeof(loff_t)))
+ goto out;
+ } else {
+ pos_in = f_in.file->f_pos;
+ }
+
+ if (off_out) {
+ if (copy_from_user(&pos_out, off_out, sizeof(loff_t)))
+ goto out;
+ } else {
+ pos_out = f_out.file->f_pos;
+ }
+
+ ret = vfs_copy_file_range(f_in.file, pos_in, f_out.file, pos_out, len,
+ flags);
+ if (ret > 0) {
+ pos_in += ret;
+ pos_out += ret;
+
+ if (off_in) {
+ if (copy_to_user(off_in, &pos_in, sizeof(loff_t)))
+ ret = -EFAULT;
+ } else {
+ f_in.file->f_pos = pos_in;
+ }
+
+ if (off_out) {
+ if (copy_to_user(off_out, &pos_out, sizeof(loff_t)))
+ ret = -EFAULT;
+ } else {
+ f_out.file->f_pos = pos_out;
+ }
+ }
+
+out:
+ fdput(f_out);
+out1:
+ fdput(f_in);
+out2:
+ return ret;
+}
+
+static int clone_verify_area(struct file *file, loff_t pos, u64 len, bool write)
+{
+ struct inode *inode = file_inode(file);
+
+ if (unlikely(pos < 0))
+ return -EINVAL;
+
+ if (unlikely((loff_t) (pos + len) < 0))
+ return -EINVAL;
+
+ if (unlikely(inode->i_flctx && mandatory_lock(inode))) {
+ loff_t end = len ? pos + len - 1 : OFFSET_MAX;
+ int retval;
+
+ retval = locks_mandatory_area(inode, file, pos, end,
+ write ? F_WRLCK : F_RDLCK);
+ if (retval < 0)
+ return retval;
+ }
+
+ return security_file_permission(file, write ? MAY_WRITE : MAY_READ);
+}
+/*
+ * Ensure that we don't remap a partial EOF block in the middle of something
+ * else. Assume that the offsets have already been checked for block
+ * alignment.
+ *
+ * For deduplication we always scale down to the previous block because we
+ * can't meaningfully compare post-EOF contents.
+ *
+ * For clone we only link a partial EOF block above the destination file's EOF.
+ */
+static int generic_remap_check_len(struct inode *inode_in,
+ struct inode *inode_out,
+ loff_t pos_out,
+ u64 *len,
+ bool is_dedupe)
+{
+ u64 blkmask = i_blocksize(inode_in) - 1;
+
+ if ((*len & blkmask) == 0)
+ return 0;
+
+ if (is_dedupe)
+ *len &= ~blkmask;
+ else if (pos_out + *len < i_size_read(inode_out))
+ return -EINVAL;
+
+ return 0;
+}
+
+/*
+ * Check that the two inodes are eligible for cloning, the ranges make
+ * sense, and then flush all dirty data. Caller must ensure that the
+ * inodes have been locked against any other modifications.
+ *
+ * Returns: 0 for "nothing to clone", 1 for "something to clone", or
+ * the usual negative error code.
+ */
+int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
+ struct inode *inode_out, loff_t pos_out,
+ u64 *len, bool is_dedupe)
+{
+ loff_t bs = inode_out->i_sb->s_blocksize;
+ loff_t blen;
+ loff_t isize;
+ bool same_inode = (inode_in == inode_out);
+ int ret;
+
+ /* Don't touch certain kinds of inodes */
+ if (IS_IMMUTABLE(inode_out))
+ return -EPERM;
+
+ if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out))
+ return -ETXTBSY;
+
+ /* Don't reflink dirs, pipes, sockets... */
+ if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
+ return -EISDIR;
+ if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
+ return -EINVAL;
+
+ /* Are we going all the way to the end? */
+ isize = i_size_read(inode_in);
+ if (isize == 0)
+ return 0;
+
+ /* Zero length dedupe exits immediately; reflink goes to EOF. */
+ if (*len == 0) {
+ if (is_dedupe || pos_in == isize)
+ return 0;
+ if (pos_in > isize)
+ return -EINVAL;
+ *len = isize - pos_in;
+ }
+
+ /* Ensure offsets don't wrap and the input is inside i_size */
+ if (pos_in + *len < pos_in || pos_out + *len < pos_out ||
+ pos_in + *len > isize)
+ return -EINVAL;
+
+ /* Don't allow dedupe past EOF in the dest file */
+ if (is_dedupe) {
+ loff_t disize;
+
+ disize = i_size_read(inode_out);
+ if (pos_out >= disize || pos_out + *len > disize)
+ return -EINVAL;
+ }
+
+ /* If we're linking to EOF, continue to the block boundary. */
+ if (pos_in + *len == isize)
+ blen = ALIGN(isize, bs) - pos_in;
+ else
+ blen = *len;
+
+ /* Only reflink if we're aligned to block boundaries */
+ if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_in + blen, bs) ||
+ !IS_ALIGNED(pos_out, bs) || !IS_ALIGNED(pos_out + blen, bs))
+ return -EINVAL;
+
+ /* Don't allow overlapped reflink within the same file */
+ if (same_inode) {
+ if (pos_out + blen > pos_in && pos_out < pos_in + blen)
+ return -EINVAL;
+ }
+
+ /* Wait for the completion of any pending IOs on both files */
+ inode_dio_wait(inode_in);
+ if (!same_inode)
+ inode_dio_wait(inode_out);
+
+ ret = filemap_write_and_wait_range(inode_in->i_mapping,
+ pos_in, pos_in + *len - 1);
+ if (ret)
+ return ret;
+
+ ret = filemap_write_and_wait_range(inode_out->i_mapping,
+ pos_out, pos_out + *len - 1);
+ if (ret)
+ return ret;
+
+ /*
+ * Check that the extents are the same.
+ */
+ if (is_dedupe) {
+ bool is_same = false;
+
+ ret = vfs_dedupe_file_range_compare(inode_in, pos_in,
+ inode_out, pos_out, *len, &is_same);
+ if (ret)
+ return ret;
+ if (!is_same)
+ return -EBADE;
+ }
+
+ ret = generic_remap_check_len(inode_in, inode_out, pos_out, len,
+ is_dedupe);
+ if (ret)
+ return ret;
+
+ return 1;
+}
+EXPORT_SYMBOL(vfs_clone_file_prep_inodes);
+
+int do_clone_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out, u64 len)
+{
+ struct inode *inode_in = file_inode(file_in);
+ struct inode *inode_out = file_inode(file_out);
+ int ret;
+
+ if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
+ return -EISDIR;
+ if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
+ return -EINVAL;
+
+ /*
+ * FICLONE/FICLONERANGE ioctls enforce that src and dest files are on
+ * the same mount. Practically, they only need to be on the same file
+ * system.
+ */
+ if (inode_in->i_sb != inode_out->i_sb)
+ return -EXDEV;
+
+ if (!(file_in->f_mode & FMODE_READ) ||
+ !(file_out->f_mode & FMODE_WRITE) ||
+ (file_out->f_flags & O_APPEND))
+ return -EBADF;
+
+ if (!file_in->f_op->clone_file_range)
+ return -EOPNOTSUPP;
+
+ ret = clone_verify_area(file_in, pos_in, len, false);
+ if (ret)
+ return ret;
+
+ ret = clone_verify_area(file_out, pos_out, len, true);
+ if (ret)
+ return ret;
+
+ if (pos_in + len > i_size_read(inode_in))
+ return -EINVAL;
+
+ ret = file_in->f_op->clone_file_range(file_in, pos_in,
+ file_out, pos_out, len);
+ if (!ret) {
+ fsnotify_access(file_in);
+ fsnotify_modify(file_out);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(do_clone_file_range);
+
+int vfs_clone_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out, u64 len)
+{
+ int ret;
+
+ file_start_write(file_out);
+ ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len);
+ file_end_write(file_out);
+
+ return ret;
+}
+EXPORT_SYMBOL(vfs_clone_file_range);
+
+/* Read a page's worth of file data into the page cache. */
+static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset)
+{
+ struct address_space *mapping;
+ struct page *page;
+ pgoff_t n;
+
+ n = offset >> PAGE_SHIFT;
+ mapping = inode->i_mapping;
+ page = read_mapping_page(mapping, n, NULL);
+ if (IS_ERR(page))
+ return page;
+ if (!PageUptodate(page)) {
+ put_page(page);
+ return ERR_PTR(-EIO);
+ }
+ return page;
+}
+
+/*
+ * Lock two pages, ensuring that we lock in offset order if the pages are from
+ * the same file.
+ */
+static void vfs_lock_two_pages(struct page *page1, struct page *page2)
+{
+ /* Always lock in order of increasing index. */
+ if (page1->index > page2->index)
+ swap(page1, page2);
+
+ lock_page(page1);
+ if (page1 != page2)
+ lock_page(page2);
+}
+
+/* Unlock two pages, being careful not to unlock the same page twice. */
+static void vfs_unlock_two_pages(struct page *page1, struct page *page2)
+{
+ unlock_page(page1);
+ if (page1 != page2)
+ unlock_page(page2);
+}
+
+/*
+ * Compare extents of two files to see if they are the same.
+ * Caller must have locked both inodes to prevent write races.
+ */
+int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
+ struct inode *dest, loff_t destoff,
+ loff_t len, bool *is_same)
+{
+ loff_t src_poff;
+ loff_t dest_poff;
+ void *src_addr;
+ void *dest_addr;
+ struct page *src_page;
+ struct page *dest_page;
+ loff_t cmp_len;
+ bool same;
+ int error;
+
+ error = -EINVAL;
+ same = true;
+ while (len) {
+ src_poff = srcoff & (PAGE_SIZE - 1);
+ dest_poff = destoff & (PAGE_SIZE - 1);
+ cmp_len = min(PAGE_SIZE - src_poff,
+ PAGE_SIZE - dest_poff);
+ cmp_len = min(cmp_len, len);
+ if (cmp_len <= 0)
+ goto out_error;
+
+ src_page = vfs_dedupe_get_page(src, srcoff);
+ if (IS_ERR(src_page)) {
+ error = PTR_ERR(src_page);
+ goto out_error;
+ }
+ dest_page = vfs_dedupe_get_page(dest, destoff);
+ if (IS_ERR(dest_page)) {
+ error = PTR_ERR(dest_page);
+ put_page(src_page);
+ goto out_error;
+ }
+
+ vfs_lock_two_pages(src_page, dest_page);
+
+ /*
+ * Now that we've locked both pages, make sure they're still
+ * mapped to the file data we're interested in. If not,
+ * someone is invalidating pages on us and we lose.
+ */
+ if (!PageUptodate(src_page) || !PageUptodate(dest_page) ||
+ src_page->mapping != src->i_mapping ||
+ dest_page->mapping != dest->i_mapping) {
+ same = false;
+ goto unlock;
+ }
+
+ src_addr = kmap_atomic(src_page);
+ dest_addr = kmap_atomic(dest_page);
+
+ flush_dcache_page(src_page);
+ flush_dcache_page(dest_page);
+
+ if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len))
+ same = false;
+
+ kunmap_atomic(dest_addr);
+ kunmap_atomic(src_addr);
+unlock:
+ vfs_unlock_two_pages(src_page, dest_page);
+ put_page(dest_page);
+ put_page(src_page);
+
+ if (!same)
+ break;
+
+ srcoff += cmp_len;
+ destoff += cmp_len;
+ len -= cmp_len;
+ }
+
+ *is_same = same;
+ return 0;
+
+out_error:
+ return error;
+}
+EXPORT_SYMBOL(vfs_dedupe_file_range_compare);
+
+int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
+{
+ struct file_dedupe_range_info *info;
+ struct inode *src = file_inode(file);
+ u64 off;
+ u64 len;
+ int i;
+ int ret;
+ bool is_admin = capable(CAP_SYS_ADMIN);
+ u16 count = same->dest_count;
+ struct file *dst_file;
+ loff_t dst_off;
+ ssize_t deduped;
+
+ if (!(file->f_mode & FMODE_READ))
+ return -EINVAL;
+
+ if (same->reserved1 || same->reserved2)
+ return -EINVAL;
+
+ off = same->src_offset;
+ len = same->src_length;
+
+ ret = -EISDIR;
+ if (S_ISDIR(src->i_mode))
+ goto out;
+
+ ret = -EINVAL;
+ if (!S_ISREG(src->i_mode))
+ goto out;
+
+ ret = clone_verify_area(file, off, len, false);
+ if (ret < 0)
+ goto out;
+ ret = 0;
+
+ if (off + len > i_size_read(src))
+ return -EINVAL;
+
+ /* pre-format output fields to sane values */
+ for (i = 0; i < count; i++) {
+ same->info[i].bytes_deduped = 0ULL;
+ same->info[i].status = FILE_DEDUPE_RANGE_SAME;
+ }
+
+ for (i = 0, info = same->info; i < count; i++, info++) {
+ struct inode *dst;
+ struct fd dst_fd = fdget(info->dest_fd);
+
+ dst_file = dst_fd.file;
+ if (!dst_file) {
+ info->status = -EBADF;
+ goto next_loop;
+ }
+ dst = file_inode(dst_file);
+
+ ret = mnt_want_write_file(dst_file);
+ if (ret) {
+ info->status = ret;
+ goto next_loop;
+ }
+
+ dst_off = info->dest_offset;
+ ret = clone_verify_area(dst_file, dst_off, len, true);
+ if (ret < 0) {
+ info->status = ret;
+ goto next_file;
+ }
+ ret = 0;
+
+ if (info->reserved) {
+ info->status = -EINVAL;
+ } else if (!(is_admin || (dst_file->f_mode & FMODE_WRITE))) {
+ info->status = -EINVAL;
+ } else if (file->f_path.mnt != dst_file->f_path.mnt) {
+ info->status = -EXDEV;
+ } else if (S_ISDIR(dst->i_mode)) {
+ info->status = -EISDIR;
+ } else if (dst_file->f_op->dedupe_file_range == NULL) {
+ info->status = -EINVAL;
+ } else {
+ deduped = dst_file->f_op->dedupe_file_range(file, off,
+ len, dst_file,
+ info->dest_offset);
+ if (deduped == -EBADE)
+ info->status = FILE_DEDUPE_RANGE_DIFFERS;
+ else if (deduped < 0)
+ info->status = deduped;
+ else
+ info->bytes_deduped += deduped;
+ }
+
+next_file:
+ mnt_drop_write_file(dst_file);
+next_loop:
+ fdput(dst_fd);
+
+ if (fatal_signal_pending(current))
+ goto out;
+ }
+
+out:
+ return ret;
+}
+EXPORT_SYMBOL(vfs_dedupe_file_range);