/* * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README */ #include <linux/capability.h> #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> #include <linux/compat.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: if (!reiserfs_attrs(inode->i_sb)) return -ENOTTY; 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 (!reiserfs_attrs(inode->i_sb)) return -ENOTTY; if (IS_RDONLY(inode)) return -EROFS; if (!is_owner_or_cap(inode)) 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 (!is_owner_or_cap(inode)) 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; } } #ifdef CONFIG_COMPAT long reiserfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct inode *inode = file->f_path.dentry->d_inode; int ret; /* These are just misnamed, they actually get/put from/to user an int */ switch (cmd) { case REISERFS_IOC32_UNPACK: cmd = REISERFS_IOC_UNPACK; break; case REISERFS_IOC32_GETFLAGS: cmd = REISERFS_IOC_GETFLAGS; break; case REISERFS_IOC32_SETFLAGS: cmd = REISERFS_IOC_SETFLAGS; break; case REISERFS_IOC32_GETVERSION: cmd = REISERFS_IOC_GETVERSION; break; case REISERFS_IOC32_SETVERSION: cmd = REISERFS_IOC_SETVERSION; break; default: return -ENOIOCTLCMD; } lock_kernel(); ret = reiserfs_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg)); unlock_kernel(); return ret; } #endif int reiserfs_commit_write(struct file *f, struct page *page, unsigned from, unsigned to); int reiserfs_prepare_write(struct file *f, struct page *page, unsigned from, unsigned to); /* ** 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; } /* we need to make sure nobody is changing the file size beneath ** us */ mutex_lock(&inode->i_mutex); reiserfs_write_lock(inode->i_sb); 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 = reiserfs_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 = reiserfs_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: mutex_unlock(&inode->i_mutex); reiserfs_write_unlock(inode->i_sb); return retval; }