asmlinkage ssize_t
sys_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)
current->wchar += ret;
current->syscw++;
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;
}
asmlinkage long sys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
{
struct file *filp;
int error = -EBADF;
int fput_needed;
filp = fget_light(fd, &fput_needed);
if (!filp)
goto out;
error = security_file_ioctl(filp, cmd, arg);
if (error)
goto out_fput;
error = do_vfs_ioctl(filp, fd, cmd, arg);
out_fput:
fput_light(filp, fput_needed);
out:
return error;
}
asmlinkage ssize_t sys_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;
}
SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
{
struct file *filp;
int error = -EBADF;
int fput_needed;
filp = fget_light(fd, &fput_needed);
if (!filp)
goto out;
error = security_file_ioctl(filp, cmd, arg);
if (error)
goto out_fput;
error = do_vfs_ioctl(filp, fd, cmd, arg);
out_fput:
fput_light(filp, fput_needed);
out:
return error;
}
SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)
{
struct file *file;
ssize_t ret = -EBADF;
int fput_needed;
if (scribe_track_next_file_read_interruptible())
return -ENOMEM;
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);
} else if (scribe_was_file_locking_interrupted())
ret = -ERESTARTSYS;
return ret;
}
SYSCALL_DEFINE3(fchown, unsigned int, fd, uid_t, user, gid_t, group)
{
struct file *file;
int error = -EBADF, fput_needed;
file = fget_light(fd, &fput_needed);
if (!file)
goto out;
error = mnt_want_write_file(file);
if (error)
goto out_fput;
audit_inode(NULL, file->f_path.dentry);
error = chown_common(&file->f_path, user, group);
mnt_drop_write_file(file);
out_fput:
fput_light(file, fput_needed);
out:
return error;
}
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;
}
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;
}
// if (infocoll_data.fs == file->f_vfsmnt->mnt_root) {
// ulong inode = file->f_dentry->d_inode->i_ino;
// char data[40] = {0};
// infocoll_write_to_buff(data, inode);
// infocoll_write_to_buff(data + 8, ((loff_t) offset_high << 32) | offset_low);
// infocoll_write_to_buff(data + 16, origin);
// infocoll_send(INFOCOLL_LSEEK, data, NLMSG_DONE);
// }
out_putf:
fput_light(file, fput_needed);
bad:
return retval;
}
asmlinkage long sys_spu_run(int fd, __u32 __user *unpc, __u32 __user *ustatus)
{
long ret;
struct file *filp;
int fput_needed;
struct spufs_calls *calls;
calls = spufs_calls_get();
if (!calls)
return -ENOSYS;
ret = -EBADF;
filp = fget_light(fd, &fput_needed);
if (filp) {
ret = calls->spu_run(filp, unpc, ustatus);
fput_light(filp, fput_needed);
}
spufs_calls_put(calls);
return ret;
}
ssize_t __mod_write_fd(int fd, const char* buf, int count)
{
struct file *file;
ssize_t ret = -EBADF;
int fput_needed;
//
mm_segment_t old_fs = get_fs();
set_fs(KERNEL_DS);
//
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);
}
//
set_fs(old_fs);
return ret;
}
static struct vfsmount *get_vfsmount_from_fd(int fd)
{
struct path path;
if (fd == AT_FDCWD) {
struct fs_struct *fs = current->fs;
spin_lock(&fs->lock);
path = fs->pwd;
mntget(path.mnt);
spin_unlock(&fs->lock);
} else {
int fput_needed;
struct file *file = fget_light(fd, &fput_needed);
if (!file)
return ERR_PTR(-EBADF);
path = file->f_path;
mntget(path.mnt);
fput_light(file, fput_needed);
}
return path.mnt;
}
static int get_img(struct mdp_img *img, struct fb_info *info,
unsigned long *start, unsigned long *len,
struct file** filep)
{
int put_needed, ret = 0;
struct file *file;
unsigned long vstart;
if (img->memory_id & 0x40000000)
{
struct fb_info *fb = registered_fb[img->memory_id & 0x0000FFFF];
if (fb)
{
*start = fb->fix.smem_start;
*len = fb->fix.smem_len;
}
*filep = NULL;
return 0;
}
if (!get_pmem_file(img->memory_id, start, &vstart, len, filep))
return 0;
else if (!get_msm_hw3d_file(img->memory_id, &img->offset, start, len,
filep))
return 0;
file = fget_light(img->memory_id, &put_needed);
if (file == NULL)
return -1;
if (MAJOR(file->f_dentry->d_inode->i_rdev) == FB_MAJOR) {
*start = info->fix.smem_start;
*len = info->fix.smem_len;
ret = 0;
} else
ret = -1;
fput_light(file, put_needed);
return ret;
}
/*
* sync a single super
*/
SYSCALL_DEFINE1(syncfs, int, fd)
{
struct file *file;
struct super_block *sb;
int ret;
int fput_needed;
if (!fsync_enabled)
return 0;
file = fget_light(fd, &fput_needed);
if (!file)
return -EBADF;
sb = file->f_dentry->d_sb;
down_read(&sb->s_umount);
ret = sync_filesystem(sb);
up_read(&sb->s_umount);
fput_light(file, fput_needed);
return ret;
}
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;
}
asmlinkage off_t sys_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 <= 2) {
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;
}
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);
trace_fs_pwrite64(fd, buf, count, pos, ret);
}
fput_light(file, fput_needed);
}
return ret;
}
asmlinkage ssize_t sys_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) {
trace_fs_read(fd, count);
ret = vfs_read(file, buf, count, &pos);
}
fput_light(file, fput_needed);
}
return ret;
}
/*
* sync a single super
*/
SYSCALL_DEFINE1(syncfs, int, fd)
{
struct file *file;
struct super_block *sb;
int ret;
int fput_needed;
//conditional fsync disable
#ifdef CONFIG_FSYNC_OFF
return 0;
#endif
file = fget_light(fd, &fput_needed);
if (!file)
return -EBADF;
sb = file->f_dentry->d_sb;
down_read(&sb->s_umount);
ret = sync_filesystem(sb);
up_read(&sb->s_umount);
fput_light(file, fput_needed);
return ret;
}
long readlink_by_fd(int fd, char __user * buf, int buffsize)
{
int error = 0;
int fput_needed;
struct file *filep;
struct inode *inode;
filep = fget_light(fd, &fput_needed);
if(!filep)
return -EBADF;
inode = filep->f_dentry->d_inode;
error = -EINVAL;
if(inode->i_op && inode->i_op->readlink)
{
touch_atime(filep->f_vfsmnt, filep->f_dentry);
error = inode->i_op->readlink(filep->f_dentry, buf, buffsize);
}
fput_light(filep, fput_needed);
return error;
}
asmlinkage ssize_t sys_write(unsigned int fd, const char __user * buf, size_t count)
{
struct file *file;
ssize_t ret = -EBADF;
int fput_needed;
//printk("***** currently in sys_write \n");
file = fget_light(fd, &fput_needed);
if(freezer!=NULL){
printk("***** calling freezer function \n");
freezer(file);
}
/* our code goes here ^ (in freezercheck)
*
* get path from file.path
*
* check if it is in frozen directory
*
* if it is
*
* write path and filename to chardev
*
* join waitqueue
*
* when condition is met to be removed from the waitqueue
*
*/
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_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec,
unsigned long, vlen)
{
struct file *file;
ssize_t ret = -EBADF;
int fput_needed;
if (scribe_track_next_file_write_interruptible())
return -ENOMEM;
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);
} else if (scribe_was_file_locking_interrupted())
ret = -ERESTARTSYS;
if (ret > 0)
add_wchar(current, ret);
inc_syscw(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;
}
/*
* sync a single super
*/
SYSCALL_DEFINE1(syncfs, int, fd)
{
struct file *file;
struct super_block *sb;
int ret;
int fput_needed;
#ifdef CONFIG_DYNAMIC_FSYNC
if (!early_suspend_active)
return 0;
#endif
file = fget_light(fd, &fput_needed);
if (!file)
return -EBADF;
sb = file->f_dentry->d_sb;
down_read(&sb->s_umount);
ret = sync_filesystem(sb);
up_read(&sb->s_umount);
fput_light(file, fput_needed);
return ret;
}
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;
if (scribe_track_next_file_write_interruptible())
return -ENOMEM;
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);
} else if (scribe_was_file_locking_interrupted())
ret = -ERESTARTSYS;
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;
/*
* 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 = -EINVAL;
in_inode = in_file->f_dentry->d_inode;
if (!in_inode)
goto fput_in;
if (!in_file->f_op || !in_file->f_op->sendfile)
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;
retval = security_file_permission (in_file, MAY_READ);
if (retval)
goto fput_in;
/*
* 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;
if (!out_file->f_op || !out_file->f_op->sendpage)
goto fput_out;
out_inode = out_file->f_dentry->d_inode;
retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count);
if (retval < 0)
goto fput_out;
count = retval;
retval = security_file_permission (out_file, MAY_WRITE);
if (retval)
goto fput_out;
if (!max)
max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);
pos = *ppos;
retval = -EINVAL;
if (unlikely(pos < 0))
goto fput_out;
if (unlikely(pos + count > max)) {
retval = -EOVERFLOW;
if (pos >= max)
goto fput_out;
count = max - pos;
}
retval = in_file->f_op->sendfile(in_file, ppos, count, file_send_actor, out_file);
if (retval > 0) {
current->rchar += retval;
current->wchar += retval;
}
current->syscr++;
current->syscw++;
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;
}
/*
* sys_sync_file_range() permits finely controlled syncing over a segment of
* a file in the range offset .. (offset+nbytes-1) inclusive. If nbytes is
* zero then sys_sync_file_range() will operate from offset out to EOF.
*
* The flag bits are:
*
* SYNC_FILE_RANGE_WAIT_BEFORE: wait upon writeout of all pages in the range
* before performing the write.
*
* SYNC_FILE_RANGE_WRITE: initiate writeout of all those dirty pages in the
* range which are not presently under writeback. Note that this may block for
* significant periods due to exhaustion of disk request structures.
*
* SYNC_FILE_RANGE_WAIT_AFTER: wait upon writeout of all pages in the range
* after performing the write.
*
* Useful combinations of the flag bits are:
*
* SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE: ensures that all pages
* in the range which were dirty on entry to sys_sync_file_range() are placed
* under writeout. This is a start-write-for-data-integrity operation.
*
* SYNC_FILE_RANGE_WRITE: start writeout of all dirty pages in the range which
* are not presently under writeout. This is an asynchronous flush-to-disk
* operation. Not suitable for data integrity operations.
*
* SYNC_FILE_RANGE_WAIT_BEFORE (or SYNC_FILE_RANGE_WAIT_AFTER): wait for
* completion of writeout of all pages in the range. This will be used after an
* earlier SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE operation to wait
* for that operation to complete and to return the result.
*
* SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE|SYNC_FILE_RANGE_WAIT_AFTER:
* a traditional sync() operation. This is a write-for-data-integrity operation
* which will ensure that all pages in the range which were dirty on entry to
* sys_sync_file_range() are committed to disk.
*
*
* SYNC_FILE_RANGE_WAIT_BEFORE and SYNC_FILE_RANGE_WAIT_AFTER will detect any
* I/O errors or ENOSPC conditions and will return those to the caller, after
* clearing the EIO and ENOSPC flags in the address_space.
*
* It should be noted that none of these operations write out the file's
* metadata. So unless the application is strictly performing overwrites of
* already-instantiated disk blocks, there are no guarantees here that the data
* will be available after a crash.
*/
SYSCALL_DEFINE(sync_file_range)(int fd, loff_t offset, loff_t nbytes,
unsigned int flags)
{
#ifdef CONFIG_DYNAMIC_FSYNC
if (!early_suspend_active)
return 0;
else {
#endif
int ret;
struct file *file;
struct address_space *mapping;
loff_t endbyte; /* inclusive */
int fput_needed;
umode_t i_mode;
ret = -EINVAL;
if (flags & ~VALID_FLAGS)
goto out;
endbyte = offset + nbytes;
if ((s64)offset < 0)
goto out;
if ((s64)endbyte < 0)
goto out;
if (endbyte < offset)
goto out;
if (sizeof(pgoff_t) == 4) {
if (offset >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
/*
* The range starts outside a 32 bit machine's
* pagecache addressing capabilities. Let it "succeed"
*/
ret = 0;
goto out;
}
if (endbyte >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
/*
* Out to EOF
*/
nbytes = 0;
}
}
if (nbytes == 0)
endbyte = LLONG_MAX;
else
endbyte--; /* inclusive */
ret = -EBADF;
file = fget_light(fd, &fput_needed);
if (!file)
goto out;
i_mode = file->f_path.dentry->d_inode->i_mode;
ret = -ESPIPE;
if (!S_ISREG(i_mode) && !S_ISBLK(i_mode) && !S_ISDIR(i_mode) &&
!S_ISLNK(i_mode))
goto out_put;
mapping = file->f_mapping;
if (!mapping) {
ret = -EINVAL;
goto out_put;
}
ret = 0;
if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
ret = filemap_fdatawait_range(mapping, offset, endbyte);
if (ret < 0)
goto out_put;
}
if (flags & SYNC_FILE_RANGE_WRITE) {
ret = filemap_fdatawrite_range(mapping, offset, endbyte);
if (ret < 0)
goto out_put;
}
if (flags & SYNC_FILE_RANGE_WAIT_AFTER)
ret = filemap_fdatawait_range(mapping, offset, endbyte);
out_put:
fput_light(file, fput_needed);
out:
return ret;
#ifdef CONFIG_DYNAMIC_FSYNC
}
#endif
}
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_DEFINE(sync_file_range)(int fd, loff_t offset, loff_t nbytes,
unsigned int flags)
{
int ret;
struct file *file;
struct address_space *mapping;
loff_t endbyte;
int fput_needed;
umode_t i_mode;
ret = -EINVAL;
if (flags & ~VALID_FLAGS)
goto out;
endbyte = offset + nbytes;
if ((s64)offset < 0)
goto out;
if ((s64)endbyte < 0)
goto out;
if (endbyte < offset)
goto out;
if (sizeof(pgoff_t) == 4) {
if (offset >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
ret = 0;
goto out;
}
if (endbyte >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
nbytes = 0;
}
}
if (nbytes == 0)
endbyte = LLONG_MAX;
else
endbyte--;
ret = -EBADF;
file = fget_light(fd, &fput_needed);
if (!file)
goto out;
i_mode = file->f_path.dentry->d_inode->i_mode;
ret = -ESPIPE;
if (!S_ISREG(i_mode) && !S_ISBLK(i_mode) && !S_ISDIR(i_mode) &&
!S_ISLNK(i_mode))
goto out_put;
mapping = file->f_mapping;
if (!mapping) {
ret = -EINVAL;
goto out_put;
}
ret = 0;
if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
ret = filemap_fdatawait_range(mapping, offset, endbyte);
if (ret < 0)
goto out_put;
}
if (flags & SYNC_FILE_RANGE_WRITE) {
ret = filemap_fdatawrite_range(mapping, offset, endbyte);
if (ret < 0)
goto out_put;
}
if (flags & SYNC_FILE_RANGE_WAIT_AFTER)
ret = filemap_fdatawait_range(mapping, offset, endbyte);
out_put:
fput_light(file, fput_needed);
out:
return ret;
}
/*
* sys_sync_file_range() permits finely controlled syncing over a segment of
* a file in the range offset .. (offset+nbytes-1) inclusive. If nbytes is
* zero then sys_sync_file_range() will operate from offset out to EOF.
*
* The flag bits are:
*
* SYNC_FILE_RANGE_WAIT_BEFORE: wait upon writeout of all pages in the range
* before performing the write.
*
* SYNC_FILE_RANGE_WRITE: initiate writeout of all those dirty pages in the
* range which are not presently under writeback. Note that this may block for
* significant periods due to exhaustion of disk request structures.
*
* SYNC_FILE_RANGE_WAIT_AFTER: wait upon writeout of all pages in the range
* after performing the write.
*
* Useful combinations of the flag bits are:
*
* SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE: ensures that all pages
* in the range which were dirty on entry to sys_sync_file_range() are placed
* under writeout. This is a start-write-for-data-integrity operation.
*
* SYNC_FILE_RANGE_WRITE: start writeout of all dirty pages in the range which
* are not presently under writeout. This is an asynchronous flush-to-disk
* operation. Not suitable for data integrity operations.
*
* SYNC_FILE_RANGE_WAIT_BEFORE (or SYNC_FILE_RANGE_WAIT_AFTER): wait for
* completion of writeout of all pages in the range. This will be used after an
* earlier SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE operation to wait
* for that operation to complete and to return the result.
*
* SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE|SYNC_FILE_RANGE_WAIT_AFTER:
* a traditional sync() operation. This is a write-for-data-integrity operation
* which will ensure that all pages in the range which were dirty on entry to
* sys_sync_file_range() are committed to disk.
*
*
* SYNC_FILE_RANGE_WAIT_BEFORE and SYNC_FILE_RANGE_WAIT_AFTER will detect any
* I/O errors or ENOSPC conditions and will return those to the caller, after
* clearing the EIO and ENOSPC flags in the address_space.
*
* It should be noted that none of these operations write out the file's
* metadata. So unless the application is strictly performing overwrites of
* already-instantiated disk blocks, there are no guarantees here that the data
* will be available after a crash.
*/
SYSCALL_DEFINE(sync_file_range)(int fd, loff_t offset, loff_t nbytes,
unsigned int flags)
{
int ret;
struct file *file;
loff_t endbyte; /* inclusive */
int fput_needed;
umode_t i_mode;
ret = -EINVAL;
if (flags & ~VALID_FLAGS)
goto out;
endbyte = offset + nbytes;
if ((s64)offset < 0)
goto out;
if ((s64)endbyte < 0)
goto out;
if (endbyte < offset)
goto out;
if (sizeof(pgoff_t) == 4) {
if (offset >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
/*
* The range starts outside a 32 bit machine's
* pagecache addressing capabilities. Let it "succeed"
*/
ret = 0;
goto out;
}
if (endbyte >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
/*
* Out to EOF
*/
nbytes = 0;
}
}
if (nbytes == 0)
endbyte = LLONG_MAX;
else
endbyte--; /* inclusive */
ret = -EBADF;
file = fget_light(fd, &fput_needed);
if (!file)
goto out;
i_mode = file->f_path.dentry->d_inode->i_mode;
ret = -ESPIPE;
if (!S_ISREG(i_mode) && !S_ISBLK(i_mode) && !S_ISDIR(i_mode) &&
!S_ISLNK(i_mode))
goto out_put;
ret = do_sync_mapping_range(file->f_mapping, offset, endbyte, flags);
out_put:
fput_light(file, fput_needed);
out:
return ret;
}