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)
{
- loff_t retval;
struct inode *inode = file->f_mapping->host;
switch (origin) {
- case SEEK_END:
- offset += inode->i_size;
- break;
- case SEEK_CUR:
- offset += file->f_pos;
+ 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;
}
- retval = -EINVAL;
- if (offset>=0 && offset<=inode->i_sb->s_maxbytes) {
- /* Special lock needed here? */
- if (offset != file->f_pos) {
- file->f_pos = offset;
- file->f_version = 0;
- }
- retval = offset;
+
+ 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 retval;
+
+ 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 n;
+ loff_t rval;
+
mutex_lock(&file->f_dentry->d_inode->i_mutex);
- n = generic_file_llseek_unlocked(file, offset, origin);
+ rval = generic_file_llseek_unlocked(file, offset, origin);
mutex_unlock(&file->f_dentry->d_inode->i_mutex);
- return n;
+
+ return rval;
}
EXPORT_SYMBOL(generic_file_llseek);
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;
}
retval = offset;
}
+out:
unlock_kernel();
return retval;
}
}
EXPORT_SYMBOL(vfs_llseek);
-asmlinkage off_t sys_lseek(unsigned int fd, off_t offset, unsigned int origin)
+SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, origin)
{
off_t retval;
struct file * file;
}
#ifdef __ARCH_WANT_SYS_LLSEEK
-asmlinkage long sys_llseek(unsigned int fd, unsigned long offset_high,
- unsigned long offset_low, loff_t __user * result,
- unsigned int origin)
+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;
file->f_pos = pos;
}
-asmlinkage ssize_t sys_read(unsigned int fd, char __user * buf, size_t count)
+SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)
{
struct file *file;
ssize_t ret = -EBADF;
return ret;
}
-asmlinkage ssize_t sys_write(unsigned int fd, const char __user * buf, size_t count)
+SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf,
+ size_t, count)
{
struct file *file;
ssize_t ret = -EBADF;
return ret;
}
-asmlinkage ssize_t sys_pread64(unsigned int fd, char __user *buf,
- size_t count, loff_t pos)
+SYSCALL_DEFINE(pread64)(unsigned int fd, char __user *buf,
+ size_t count, loff_t pos)
{
struct file *file;
ssize_t ret = -EBADF;
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
-asmlinkage ssize_t sys_pwrite64(unsigned int fd, const char __user *buf,
- size_t count, loff_t pos)
+SYSCALL_DEFINE(pwrite64)(unsigned int fd, const char __user *buf,
+ size_t count, loff_t pos)
{
struct file *file;
ssize_t ret = -EBADF;
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
EXPORT_SYMBOL(vfs_writev);
-asmlinkage ssize_t
-sys_readv(unsigned long fd, const struct iovec __user *vec, unsigned long vlen)
+SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen)
{
struct file *file;
ssize_t ret = -EBADF;
return ret;
}
-asmlinkage ssize_t
-sys_writev(unsigned long fd, const struct iovec __user *vec, unsigned long vlen)
+SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec,
+ unsigned long, vlen)
{
struct file *file;
ssize_t ret = -EBADF;
return retval;
}
-asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, off_t __user *offset, size_t count)
+SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count)
{
loff_t pos;
off_t off;
return do_sendfile(out_fd, in_fd, NULL, count, 0);
}
-asmlinkage ssize_t sys_sendfile64(int out_fd, int in_fd, loff_t __user *offset, size_t count)
+SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count)
{
loff_t pos;
ssize_t ret;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff