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authorKim Kibum <kb0929.kim@samsung.com>2012-04-29 16:59:19 +0900
committerKim Kibum <kb0929.kim@samsung.com>2012-04-29 16:59:19 +0900
commitc1775d1a93a77a57380a4ce87ac3a8f807c944b2 (patch)
treee1f233f2af38ee247a677082198dd3a69a12a5a1 /fs/read_write.c
parent2c2dcd5ffef2e97176e6a55e45512177e55e6fb9 (diff)
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upload tizen1.0 sourceHEADmaster2.0alpha
Diffstat (limited to 'fs/read_write.c')
-rw-r--r--fs/read_write.c931
1 files changed, 931 insertions, 0 deletions
diff --git a/fs/read_write.c b/fs/read_write.c
new file mode 100644
index 00000000..74e36586
--- /dev/null
+++ b/fs/read_write.c
@@ -0,0 +1,931 @@
+/*
+ * linux/fs/read_write.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#include <linux/slab.h>
+#include <linux/stat.h>
+#include <linux/fcntl.h>
+#include <linux/file.h>
+#include <linux/uio.h>
+#include <linux/smp_lock.h>
+#include <linux/fsnotify.h>
+#include <linux/security.h>
+#include <linux/module.h>
+#include <linux/syscalls.h>
+#include <linux/pagemap.h>
+#include <linux/splice.h>
+#include "read_write.h"
+
+#include <asm/uaccess.h>
+#include <asm/unistd.h>
+
+const struct file_operations generic_ro_fops = {
+ .llseek = generic_file_llseek,
+ .read = do_sync_read,
+ .aio_read = generic_file_aio_read,
+ .mmap = generic_file_readonly_mmap,
+ .splice_read = generic_file_splice_read,
+};
+
+EXPORT_SYMBOL(generic_ro_fops);
+
+/**
+ * generic_file_llseek_unlocked - lockless generic llseek implementation
+ * @file: file structure to seek on
+ * @offset: file offset to seek to
+ * @origin: type of seek
+ *
+ * Updates the file offset to the value specified by @offset and @origin.
+ * Locking must be provided by the caller.
+ */
+loff_t
+generic_file_llseek_unlocked(struct file *file, loff_t offset, int origin)
+{
+ struct inode *inode = file->f_mapping->host;
+
+ switch (origin) {
+ case SEEK_END:
+ offset += inode->i_size;
+ 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;
+ offset += file->f_pos;
+ break;
+ }
+
+ if (offset < 0 || offset > inode->i_sb->s_maxbytes)
+ return -EINVAL;
+
+ /* Special lock needed here? */
+ if (offset != file->f_pos) {
+ file->f_pos = offset;
+ file->f_version = 0;
+ }
+
+ return offset;
+}
+EXPORT_SYMBOL(generic_file_llseek_unlocked);
+
+/**
+ * generic_file_llseek - generic llseek implementation for regular files
+ * @file: file structure to seek on
+ * @offset: file offset to seek to
+ * @origin: 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 @origin under i_mutex.
+ */
+loff_t generic_file_llseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t rval;
+
+ mutex_lock(&file->f_dentry->d_inode->i_mutex);
+ rval = generic_file_llseek_unlocked(file, offset, origin);
+ mutex_unlock(&file->f_dentry->d_inode->i_mutex);
+
+ return rval;
+}
+EXPORT_SYMBOL(generic_file_llseek);
+
+/**
+ * noop_llseek - No Operation Performed llseek implementation
+ * @file: file structure to seek on
+ * @offset: file offset to seek to
+ * @origin: 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 origin)
+{
+ return file->f_pos;
+}
+EXPORT_SYMBOL(noop_llseek);
+
+loff_t no_llseek(struct file *file, loff_t offset, int origin)
+{
+ return -ESPIPE;
+}
+EXPORT_SYMBOL(no_llseek);
+
+loff_t default_llseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t retval;
+
+ lock_kernel();
+ switch (origin) {
+ case SEEK_END:
+ offset += i_size_read(file->f_path.dentry->d_inode);
+ break;
+ case SEEK_CUR:
+ if (offset == 0) {
+ retval = file->f_pos;
+ goto out;
+ }
+ offset += file->f_pos;
+ }
+ retval = -EINVAL;
+ if (offset >= 0) {
+ if (offset != file->f_pos) {
+ file->f_pos = offset;
+ file->f_version = 0;
+ }
+ retval = offset;
+ }
+out:
+ unlock_kernel();
+ return retval;
+}
+EXPORT_SYMBOL(default_llseek);
+
+loff_t vfs_llseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t (*fn)(struct file *, loff_t, int);
+
+ fn = no_llseek;
+ if (file->f_mode & FMODE_LSEEK) {
+ fn = default_llseek;
+ if (file->f_op && file->f_op->llseek)
+ fn = file->f_op->llseek;
+ }
+ return fn(file, offset, origin);
+}
+EXPORT_SYMBOL(vfs_llseek);
+
+SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, origin)
+{
+ off_t retval;
+ struct file * file;
+ int fput_needed;
+
+ retval = -EBADF;
+ file = fget_light(fd, &fput_needed);
+ if (!file)
+ goto bad;
+
+ retval = -EINVAL;
+ if (origin <= SEEK_MAX) {
+ loff_t res = vfs_llseek(file, offset, origin);
+ retval = res;
+ if (res != (loff_t)retval)
+ retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */
+ }
+ fput_light(file, fput_needed);
+bad:
+ return retval;
+}
+
+#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, origin)
+{
+ int retval;
+ struct file * file;
+ loff_t offset;
+ int fput_needed;
+
+ retval = -EBADF;
+ file = fget_light(fd, &fput_needed);
+ if (!file)
+ goto bad;
+
+ retval = -EINVAL;
+ if (origin > SEEK_MAX)
+ goto out_putf;
+
+ offset = vfs_llseek(file, ((loff_t) offset_high << 32) | offset_low,
+ origin);
+
+ retval = (int)offset;
+ if (offset >= 0) {
+ retval = -EFAULT;
+ if (!copy_to_user(result, &offset, sizeof(offset)))
+ retval = 0;
+ }
+out_putf:
+ fput_light(file, fput_needed);
+bad:
+ return retval;
+}
+#endif
+
+/*
+ * rw_verify_area doesn't like huge counts. We limit
+ * them to something that fits in "int" so that others
+ * won't have to do range checks all the time.
+ */
+#define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK)
+
+int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count)
+{
+ struct inode *inode;
+ loff_t pos;
+ int retval = -EINVAL;
+
+ inode = file->f_path.dentry->d_inode;
+ if (unlikely((ssize_t) count < 0))
+ return retval;
+ pos = *ppos;
+ if (unlikely((pos < 0) || (loff_t) (pos + count) < 0))
+ return retval;
+
+ if (unlikely(inode->i_flock && mandatory_lock(inode))) {
+ retval = locks_mandatory_area(
+ read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE,
+ inode, file, pos, count);
+ if (retval < 0)
+ return retval;
+ }
+ retval = security_file_permission(file,
+ read_write == READ ? MAY_READ : MAY_WRITE);
+ if (retval)
+ return retval;
+ return count > MAX_RW_COUNT ? MAX_RW_COUNT : count;
+}
+
+static void wait_on_retry_sync_kiocb(struct kiocb *iocb)
+{
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ if (!kiocbIsKicked(iocb))
+ schedule();
+ else
+ kiocbClearKicked(iocb);
+ __set_current_state(TASK_RUNNING);
+}
+
+ssize_t do_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;
+ ssize_t ret;
+
+ init_sync_kiocb(&kiocb, filp);
+ kiocb.ki_pos = *ppos;
+ kiocb.ki_left = len;
+ kiocb.ki_nbytes = len;
+
+ for (;;) {
+ ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos);
+ if (ret != -EIOCBRETRY)
+ break;
+ wait_on_retry_sync_kiocb(&kiocb);
+ }
+
+ if (-EIOCBQUEUED == ret)
+ ret = wait_on_sync_kiocb(&kiocb);
+ *ppos = kiocb.ki_pos;
+ return ret;
+}
+
+EXPORT_SYMBOL(do_sync_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_op || (!file->f_op->read && !file->f_op->aio_read))
+ return -EINVAL;
+ if (unlikely(!access_ok(VERIFY_WRITE, buf, count)))
+ return -EFAULT;
+
+ ret = rw_verify_area(READ, file, pos, count);
+ if (ret >= 0) {
+ count = ret;
+ if (file->f_op->read)
+ ret = file->f_op->read(file, buf, count, pos);
+ else
+ ret = do_sync_read(file, buf, count, pos);
+ if (ret > 0) {
+ fsnotify_access(file);
+ add_rchar(current, ret);
+ }
+ inc_syscr(current);
+ }
+
+ return ret;
+}
+
+EXPORT_SYMBOL(vfs_read);
+
+ssize_t do_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;
+ ssize_t ret;
+
+ init_sync_kiocb(&kiocb, filp);
+ kiocb.ki_pos = *ppos;
+ kiocb.ki_left = len;
+ kiocb.ki_nbytes = len;
+
+ for (;;) {
+ ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos);
+ if (ret != -EIOCBRETRY)
+ break;
+ wait_on_retry_sync_kiocb(&kiocb);
+ }
+
+ if (-EIOCBQUEUED == ret)
+ ret = wait_on_sync_kiocb(&kiocb);
+ *ppos = kiocb.ki_pos;
+ return ret;
+}
+
+EXPORT_SYMBOL(do_sync_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_op || (!file->f_op->write && !file->f_op->aio_write))
+ return -EINVAL;
+ if (unlikely(!access_ok(VERIFY_READ, buf, count)))
+ return -EFAULT;
+
+ ret = rw_verify_area(WRITE, file, pos, count);
+ if (ret >= 0) {
+ count = ret;
+ if (file->f_op->write)
+ ret = file->f_op->write(file, buf, count, pos);
+ else
+ ret = do_sync_write(file, buf, count, pos);
+ if (ret > 0) {
+ fsnotify_modify(file);
+ add_wchar(current, ret);
+ }
+ inc_syscw(current);
+ }
+
+ return ret;
+}
+
+EXPORT_SYMBOL(vfs_write);
+
+static inline loff_t file_pos_read(struct file *file)
+{
+ return file->f_pos;
+}
+
+static inline void file_pos_write(struct file *file, loff_t pos)
+{
+ file->f_pos = pos;
+}
+
+SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)
+{
+ struct file *file;
+ ssize_t ret = -EBADF;
+ int fput_needed;
+
+ file = fget_light(fd, &fput_needed);
+ if (file) {
+ loff_t pos = file_pos_read(file);
+ ret = vfs_read(file, buf, count, &pos);
+ file_pos_write(file, pos);
+ fput_light(file, fput_needed);
+ }
+
+ return ret;
+}
+
+SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf,
+ size_t, count)
+{
+ struct file *file;
+ ssize_t ret = -EBADF;
+ int fput_needed;
+
+ file = fget_light(fd, &fput_needed);
+ if (file) {
+ loff_t pos = file_pos_read(file);
+ ret = vfs_write(file, buf, count, &pos);
+ file_pos_write(file, pos);
+ fput_light(file, fput_needed);
+ }
+
+ return ret;
+}
+
+SYSCALL_DEFINE(pread64)(unsigned int fd, char __user *buf,
+ size_t count, loff_t pos)
+{
+ struct file *file;
+ ssize_t ret = -EBADF;
+ int fput_needed;
+
+ if (pos < 0)
+ return -EINVAL;
+
+ file = fget_light(fd, &fput_needed);
+ if (file) {
+ ret = -ESPIPE;
+ if (file->f_mode & FMODE_PREAD)
+ ret = vfs_read(file, buf, count, &pos);
+ fput_light(file, fput_needed);
+ }
+
+ return ret;
+}
+#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
+asmlinkage long SyS_pread64(long fd, long buf, long count, loff_t pos)
+{
+ return SYSC_pread64((unsigned int) fd, (char __user *) buf,
+ (size_t) count, pos);
+}
+SYSCALL_ALIAS(sys_pread64, SyS_pread64);
+#endif
+
+SYSCALL_DEFINE(pwrite64)(unsigned int fd, const char __user *buf,
+ size_t count, loff_t pos)
+{
+ struct file *file;
+ ssize_t ret = -EBADF;
+ int fput_needed;
+
+ if (pos < 0)
+ return -EINVAL;
+
+ file = fget_light(fd, &fput_needed);
+ if (file) {
+ ret = -ESPIPE;
+ if (file->f_mode & FMODE_PWRITE)
+ ret = vfs_write(file, buf, count, &pos);
+ fput_light(file, fput_needed);
+ }
+
+ return ret;
+}
+#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
+asmlinkage long SyS_pwrite64(long fd, long buf, long count, loff_t pos)
+{
+ return SYSC_pwrite64((unsigned int) fd, (const char __user *) buf,
+ (size_t) count, pos);
+}
+SYSCALL_ALIAS(sys_pwrite64, SyS_pwrite64);
+#endif
+
+/*
+ * 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);
+
+ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov,
+ unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn)
+{
+ struct kiocb kiocb;
+ ssize_t ret;
+
+ init_sync_kiocb(&kiocb, filp);
+ kiocb.ki_pos = *ppos;
+ kiocb.ki_left = len;
+ kiocb.ki_nbytes = len;
+
+ for (;;) {
+ ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos);
+ if (ret != -EIOCBRETRY)
+ break;
+ wait_on_retry_sync_kiocb(&kiocb);
+ }
+
+ if (ret == -EIOCBQUEUED)
+ ret = wait_on_sync_kiocb(&kiocb);
+ *ppos = kiocb.ki_pos;
+ return ret;
+}
+
+/* Do it by hand, with file-ops */
+ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov,
+ unsigned long nr_segs, loff_t *ppos, io_fn_t fn)
+{
+ struct iovec *vector = iov;
+ ssize_t ret = 0;
+
+ while (nr_segs > 0) {
+ void __user *base;
+ size_t len;
+ ssize_t nr;
+
+ base = vector->iov_base;
+ len = vector->iov_len;
+ vector++;
+ nr_segs--;
+
+ nr = fn(filp, base, len, ppos);
+
+ if (nr < 0) {
+ if (!ret)
+ ret = nr;
+ break;
+ }
+ ret += nr;
+ if (nr != len)
+ break;
+ }
+
+ return ret;
+}
+
+/* A write operation does a read from user space and vice versa */
+#define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ)
+
+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.
+ */
+ 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 + len < ret)) {
+ ret = -EINVAL;
+ goto out;
+ }
+ if (unlikely(!access_ok(vrfy_dir(type), buf, len))) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ ret += len;
+ }
+out:
+ *ret_pointer = iov;
+ return ret;
+}
+
+static ssize_t do_readv_writev(int type, struct file *file,
+ const struct iovec __user * uvector,
+ unsigned long nr_segs, loff_t *pos)
+{
+ size_t tot_len;
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ ssize_t ret;
+ io_fn_t fn;
+ iov_fn_t fnv;
+
+ if (!file->f_op) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = rw_copy_check_uvector(type, uvector, nr_segs,
+ ARRAY_SIZE(iovstack), iovstack, &iov);
+ if (ret <= 0)
+ goto out;
+
+ tot_len = ret;
+ ret = rw_verify_area(type, file, pos, tot_len);
+ if (ret < 0)
+ goto out;
+
+ fnv = NULL;
+ if (type == READ) {
+ fn = file->f_op->read;
+ fnv = file->f_op->aio_read;
+ } else {
+ fn = (io_fn_t)file->f_op->write;
+ fnv = file->f_op->aio_write;
+ }
+
+ if (fnv)
+ ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
+ pos, fnv);
+ else
+ ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);
+
+out:
+ if (iov != iovstack)
+ kfree(iov);
+ if ((ret + (type == READ)) > 0) {
+ if (type == READ)
+ fsnotify_access(file);
+ else
+ fsnotify_modify(file);
+ }
+ return ret;
+}
+
+ssize_t vfs_readv(struct file *file, const struct iovec __user *vec,
+ unsigned long vlen, loff_t *pos)
+{
+ if (!(file->f_mode & FMODE_READ))
+ return -EBADF;
+ if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read))
+ return -EINVAL;
+
+ return do_readv_writev(READ, file, vec, vlen, pos);
+}
+
+EXPORT_SYMBOL(vfs_readv);
+
+ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
+ unsigned long vlen, loff_t *pos)
+{
+ if (!(file->f_mode & FMODE_WRITE))
+ return -EBADF;
+ if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write))
+ return -EINVAL;
+
+ return do_readv_writev(WRITE, file, vec, vlen, pos);
+}
+
+EXPORT_SYMBOL(vfs_writev);
+
+SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen)
+{
+ struct file *file;
+ ssize_t ret = -EBADF;
+ int fput_needed;
+
+ file = fget_light(fd, &fput_needed);
+ if (file) {
+ loff_t pos = file_pos_read(file);
+ ret = vfs_readv(file, vec, vlen, &pos);
+ file_pos_write(file, pos);
+ fput_light(file, fput_needed);
+ }
+
+ if (ret > 0)
+ add_rchar(current, ret);
+ inc_syscr(current);
+ return ret;
+}
+
+SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen)
+{
+ struct file *file;
+ ssize_t ret = -EBADF;
+ int fput_needed;
+
+ file = fget_light(fd, &fput_needed);
+ if (file) {
+ loff_t pos = file_pos_read(file);
+ ret = vfs_writev(file, vec, vlen, &pos);
+ file_pos_write(file, pos);
+ fput_light(file, fput_needed);
+ }
+
+ 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;
+}
+
+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);
+ struct file *file;
+ ssize_t ret = -EBADF;
+ int fput_needed;
+
+ if (pos < 0)
+ return -EINVAL;
+
+ file = fget_light(fd, &fput_needed);
+ if (file) {
+ ret = -ESPIPE;
+ if (file->f_mode & FMODE_PREAD)
+ ret = vfs_readv(file, vec, vlen, &pos);
+ fput_light(file, fput_needed);
+ }
+
+ if (ret > 0)
+ add_rchar(current, ret);
+ inc_syscr(current);
+ return ret;
+}
+
+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);
+ struct file *file;
+ ssize_t ret = -EBADF;
+ int fput_needed;
+
+ if (pos < 0)
+ return -EINVAL;
+
+ file = fget_light(fd, &fput_needed);
+ if (file) {
+ ret = -ESPIPE;
+ if (file->f_mode & FMODE_PWRITE)
+ ret = vfs_writev(file, vec, vlen, &pos);
+ fput_light(file, fput_needed);
+ }
+
+ if (ret > 0)
+ add_wchar(current, ret);
+ inc_syscw(current);
+ return ret;
+}
+
+static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
+ size_t count, loff_t max)
+{
+ struct file * in_file, * out_file;
+ struct inode * in_inode, * out_inode;
+ loff_t pos;
+ ssize_t retval;
+ int fput_needed_in, fput_needed_out, fl;
+
+ /*
+ * Get input file, and verify that it is ok..
+ */
+ retval = -EBADF;
+ in_file = fget_light(in_fd, &fput_needed_in);
+ if (!in_file)
+ goto out;
+ if (!(in_file->f_mode & FMODE_READ))
+ goto fput_in;
+ retval = -ESPIPE;
+ if (!ppos)
+ ppos = &in_file->f_pos;
+ else
+ if (!(in_file->f_mode & FMODE_PREAD))
+ goto fput_in;
+ retval = rw_verify_area(READ, in_file, ppos, count);
+ if (retval < 0)
+ goto fput_in;
+ count = retval;
+
+ /*
+ * Get output file, and verify that it is ok..
+ */
+ retval = -EBADF;
+ out_file = fget_light(out_fd, &fput_needed_out);
+ if (!out_file)
+ goto fput_in;
+ if (!(out_file->f_mode & FMODE_WRITE))
+ goto fput_out;
+ retval = -EINVAL;
+ in_inode = in_file->f_path.dentry->d_inode;
+ out_inode = out_file->f_path.dentry->d_inode;
+ retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count);
+ if (retval < 0)
+ goto fput_out;
+ count = retval;
+
+ if (!max)
+ max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);
+
+ pos = *ppos;
+ 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
+ retval = do_splice_direct(in_file, ppos, out_file, count, fl);
+
+ if (retval > 0) {
+ add_rchar(current, retval);
+ add_wchar(current, retval);
+ }
+
+ inc_syscr(current);
+ inc_syscw(current);
+ if (*ppos > max)
+ retval = -EOVERFLOW;
+
+fput_out:
+ fput_light(out_file, fput_needed_out);
+fput_in:
+ fput_light(in_file, fput_needed_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);
+}