diff options
Diffstat (limited to 'fs/reiserfs/ioctl.c')
| -rw-r--r-- | fs/reiserfs/ioctl.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/fs/reiserfs/ioctl.c b/fs/reiserfs/ioctl.c new file mode 100644 index 00000000000..94dc42475a0 --- /dev/null +++ b/fs/reiserfs/ioctl.c @@ -0,0 +1,151 @@ +/* + * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README + */ + +#include <linux/fs.h> +#include <linux/reiserfs_fs.h> +#include <linux/time.h> +#include <asm/uaccess.h> +#include <linux/pagemap.h> +#include <linux/smp_lock.h> + +static int reiserfs_unpack (struct inode * inode, struct file * filp); + +/* +** reiserfs_ioctl - handler for ioctl for inode +** supported commands: +** 1) REISERFS_IOC_UNPACK - try to unpack tail from direct item into indirect +** and prevent packing file (argument arg has to be non-zero) +** 2) REISERFS_IOC_[GS]ETFLAGS, REISERFS_IOC_[GS]ETVERSION +** 3) That's all for a while ... +*/ +int reiserfs_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, + unsigned long arg) +{ + unsigned int flags; + + switch (cmd) { + case REISERFS_IOC_UNPACK: + if( S_ISREG( inode -> i_mode ) ) { + if (arg) + return reiserfs_unpack (inode, filp); + else + return 0; + } else + return -ENOTTY; + /* following two cases are taken from fs/ext2/ioctl.c by Remy + Card (card@masi.ibp.fr) */ + case REISERFS_IOC_GETFLAGS: + flags = REISERFS_I(inode) -> i_attrs; + i_attrs_to_sd_attrs( inode, ( __u16 * ) &flags ); + return put_user(flags, (int __user *) arg); + case REISERFS_IOC_SETFLAGS: { + if (IS_RDONLY(inode)) + return -EROFS; + + if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + return -EPERM; + + if (get_user(flags, (int __user *) arg)) + return -EFAULT; + + if ( ( ( flags ^ REISERFS_I(inode) -> i_attrs) & ( REISERFS_IMMUTABLE_FL | REISERFS_APPEND_FL)) && + !capable( CAP_LINUX_IMMUTABLE ) ) + return -EPERM; + + if( ( flags & REISERFS_NOTAIL_FL ) && + S_ISREG( inode -> i_mode ) ) { + int result; + + result = reiserfs_unpack( inode, filp ); + if( result ) + return result; + } + sd_attrs_to_i_attrs( flags, inode ); + REISERFS_I(inode) -> i_attrs = flags; + inode->i_ctime = CURRENT_TIME_SEC; + mark_inode_dirty(inode); + return 0; + } + case REISERFS_IOC_GETVERSION: + return put_user(inode->i_generation, (int __user *) arg); + case REISERFS_IOC_SETVERSION: + if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) + return -EPERM; + if (IS_RDONLY(inode)) + return -EROFS; + if (get_user(inode->i_generation, (int __user *) arg)) + return -EFAULT; + inode->i_ctime = CURRENT_TIME_SEC; + mark_inode_dirty(inode); + return 0; + default: + return -ENOTTY; + } +} + +/* +** reiserfs_unpack +** Function try to convert tail from direct item into indirect. +** It set up nopack attribute in the REISERFS_I(inode)->nopack +*/ +static int reiserfs_unpack (struct inode * inode, struct file * filp) +{ + int retval = 0; + int index ; + struct page *page ; + struct address_space *mapping ; + unsigned long write_from ; + unsigned long blocksize = inode->i_sb->s_blocksize ; + + if (inode->i_size == 0) { + REISERFS_I(inode)->i_flags |= i_nopack_mask; + return 0 ; + } + /* ioctl already done */ + if (REISERFS_I(inode)->i_flags & i_nopack_mask) { + return 0 ; + } + reiserfs_write_lock(inode->i_sb); + + /* we need to make sure nobody is changing the file size beneath + ** us + */ + down(&inode->i_sem) ; + + write_from = inode->i_size & (blocksize - 1) ; + /* if we are on a block boundary, we are already unpacked. */ + if ( write_from == 0) { + REISERFS_I(inode)->i_flags |= i_nopack_mask; + goto out ; + } + + /* we unpack by finding the page with the tail, and calling + ** reiserfs_prepare_write on that page. This will force a + ** reiserfs_get_block to unpack the tail for us. + */ + index = inode->i_size >> PAGE_CACHE_SHIFT ; + mapping = inode->i_mapping ; + page = grab_cache_page(mapping, index) ; + retval = -ENOMEM; + if (!page) { + goto out ; + } + retval = mapping->a_ops->prepare_write(NULL, page, write_from, write_from) ; + if (retval) + goto out_unlock ; + + /* conversion can change page contents, must flush */ + flush_dcache_page(page) ; + retval = mapping->a_ops->commit_write(NULL, page, write_from, write_from) ; + REISERFS_I(inode)->i_flags |= i_nopack_mask; + +out_unlock: + unlock_page(page) ; + page_cache_release(page) ; + +out: + up(&inode->i_sem) ; + reiserfs_write_unlock(inode->i_sb); + return retval; +} |