diff options
Diffstat (limited to 'fs/open.c')
| -rw-r--r-- | fs/open.c | 73 |
1 files changed, 70 insertions, 3 deletions
diff --git a/fs/open.c b/fs/open.c index 0d515d16197..a6b054edacb 100644 --- a/fs/open.c +++ b/fs/open.c @@ -26,6 +26,7 @@ #include <linux/syscalls.h> #include <linux/rcupdate.h> #include <linux/audit.h> +#include <linux/falloc.h> int vfs_statfs(struct dentry *dentry, struct kstatfs *buf) { @@ -352,6 +353,64 @@ asmlinkage long sys_ftruncate64(unsigned int fd, loff_t length) } #endif +asmlinkage long sys_fallocate(int fd, int mode, loff_t offset, loff_t len) +{ + struct file *file; + struct inode *inode; + long ret = -EINVAL; + + if (offset < 0 || len <= 0) + goto out; + + /* Return error if mode is not supported */ + ret = -EOPNOTSUPP; + if (mode && !(mode & FALLOC_FL_KEEP_SIZE)) + goto out; + + ret = -EBADF; + file = fget(fd); + if (!file) + goto out; + if (!(file->f_mode & FMODE_WRITE)) + goto out_fput; + /* + * Revalidate the write permissions, in case security policy has + * changed since the files were opened. + */ + ret = security_file_permission(file, MAY_WRITE); + if (ret) + goto out_fput; + + inode = file->f_path.dentry->d_inode; + + ret = -ESPIPE; + if (S_ISFIFO(inode->i_mode)) + goto out_fput; + + ret = -ENODEV; + /* + * Let individual file system decide if it supports preallocation + * for directories or not. + */ + if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode)) + goto out_fput; + + ret = -EFBIG; + /* Check for wrap through zero too */ + if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0)) + goto out_fput; + + if (inode->i_op && inode->i_op->fallocate) + ret = inode->i_op->fallocate(inode, mode, offset, len); + else + ret = -ENOSYS; + +out_fput: + fput(file); +out: + return ret; +} + /* * access() needs to use the real uid/gid, not the effective uid/gid. * We do this by temporarily clearing all FS-related capabilities and @@ -855,7 +914,7 @@ EXPORT_SYMBOL(dentry_open); /* * Find an empty file descriptor entry, and mark it busy. */ -int get_unused_fd(void) +int get_unused_fd_flags(int flags) { struct files_struct * files = current->files; int fd, error; @@ -891,7 +950,10 @@ repeat: } FD_SET(fd, fdt->open_fds); - FD_CLR(fd, fdt->close_on_exec); + if (flags & O_CLOEXEC) + FD_SET(fd, fdt->close_on_exec); + else + FD_CLR(fd, fdt->close_on_exec); files->next_fd = fd + 1; #if 1 /* Sanity check */ @@ -907,6 +969,11 @@ out: return error; } +int get_unused_fd(void) +{ + return get_unused_fd_flags(0); +} + EXPORT_SYMBOL(get_unused_fd); static void __put_unused_fd(struct files_struct *files, unsigned int fd) @@ -959,7 +1026,7 @@ long do_sys_open(int dfd, const char __user *filename, int flags, int mode) int fd = PTR_ERR(tmp); if (!IS_ERR(tmp)) { - fd = get_unused_fd(); + fd = get_unused_fd_flags(flags); if (fd >= 0) { struct file *f = do_filp_open(dfd, tmp, flags, mode); if (IS_ERR(f)) { |