diff options
Diffstat (limited to 'fs/read_write.c')
| -rw-r--r-- | fs/read_write.c | 62 |
1 files changed, 46 insertions, 16 deletions
diff --git a/fs/read_write.c b/fs/read_write.c index 969a6d9c020b..400fe81c973e 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -50,6 +50,14 @@ generic_file_llseek_unlocked(struct file *file, loff_t offset, int origin) 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; } @@ -105,6 +113,10 @@ loff_t default_llseek(struct file *file, loff_t offset, int origin) 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; @@ -115,6 +127,7 @@ loff_t default_llseek(struct file *file, loff_t offset, int origin) } retval = offset; } +out: unlock_kernel(); return retval; } @@ -134,7 +147,7 @@ loff_t vfs_llseek(struct file *file, loff_t offset, int origin) } 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; @@ -158,9 +171,9 @@ bad: } #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; @@ -356,7 +369,7 @@ static inline void file_pos_write(struct file *file, loff_t pos) 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; @@ -373,7 +386,8 @@ asmlinkage ssize_t sys_read(unsigned int fd, char __user * buf, size_t count) 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; @@ -390,8 +404,8 @@ asmlinkage ssize_t sys_write(unsigned int fd, const char __user * buf, size_t co 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; @@ -410,9 +424,17 @@ asmlinkage ssize_t sys_pread64(unsigned int fd, char __user *buf, 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; @@ -431,6 +453,14 @@ asmlinkage ssize_t sys_pwrite64(unsigned int fd, const char __user *buf, 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 @@ -659,8 +689,8 @@ ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, 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; @@ -680,8 +710,8 @@ sys_readv(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) 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; @@ -799,7 +829,7 @@ out: 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; @@ -818,7 +848,7 @@ asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, off_t __user *offset, siz 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; |