/* * file.c * * PURPOSE * File handling routines for the OSTA-UDF(tm) filesystem. * * COPYRIGHT * This file is distributed under the terms of the GNU General Public * License (GPL). Copies of the GPL can be obtained from: * ftp://prep.ai.mit.edu/pub/gnu/GPL * Each contributing author retains all rights to their own work. * * (C) 1998-1999 Dave Boynton * (C) 1998-2004 Ben Fennema * (C) 1999-2000 Stelias Computing Inc * * HISTORY * * 10/02/98 dgb Attempt to integrate into udf.o * 10/07/98 Switched to using generic_readpage, etc., like isofs * And it works! * 12/06/98 blf Added udf_file_read. uses generic_file_read for all cases but * ICBTAG_FLAG_AD_IN_ICB. * 04/06/99 64 bit file handling on 32 bit systems taken from ext2 file.c * 05/12/99 Preliminary file write support */ #include "udfdecl.h" #include #include #include #include /* memset */ #include #include #include #include #include "udf_i.h" #include "udf_sb.h" static vm_fault_t udf_page_mkwrite(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct inode *inode = file_inode(vma->vm_file); struct address_space *mapping = inode->i_mapping; struct page *page = vmf->page; loff_t size; unsigned int end; vm_fault_t ret = VM_FAULT_LOCKED; int err; sb_start_pagefault(inode->i_sb); file_update_time(vma->vm_file); filemap_invalidate_lock_shared(mapping); lock_page(page); size = i_size_read(inode); if (page->mapping != inode->i_mapping || page_offset(page) >= size) { unlock_page(page); ret = VM_FAULT_NOPAGE; goto out_unlock; } /* Space is already allocated for in-ICB file */ if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) goto out_dirty; if (page->index == size >> PAGE_SHIFT) end = size & ~PAGE_MASK; else end = PAGE_SIZE; err = __block_write_begin(page, 0, end, udf_get_block); if (!err) err = block_commit_write(page, 0, end); if (err < 0) { unlock_page(page); ret = block_page_mkwrite_return(err); goto out_unlock; } out_dirty: set_page_dirty(page); wait_for_stable_page(page); out_unlock: filemap_invalidate_unlock_shared(mapping); sb_end_pagefault(inode->i_sb); return ret; } static const struct vm_operations_struct udf_file_vm_ops = { .fault = filemap_fault, .map_pages = filemap_map_pages, .page_mkwrite = udf_page_mkwrite, }; static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from) { ssize_t retval; struct file *file = iocb->ki_filp; struct inode *inode = file_inode(file); struct udf_inode_info *iinfo = UDF_I(inode); inode_lock(inode); retval = generic_write_checks(iocb, from); if (retval <= 0) goto out; if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB && inode->i_sb->s_blocksize < (udf_file_entry_alloc_offset(inode) + iocb->ki_pos + iov_iter_count(from))) { filemap_invalidate_lock(inode->i_mapping); retval = udf_expand_file_adinicb(inode); filemap_invalidate_unlock(inode->i_mapping); if (retval) goto out; } retval = __generic_file_write_iter(iocb, from); out: if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB && retval > 0) { down_write(&iinfo->i_data_sem); iinfo->i_lenAlloc = inode->i_size; up_write(&iinfo->i_data_sem); } inode_unlock(inode); if (retval > 0) { mark_inode_dirty(inode); retval = generic_write_sync(iocb, retval); } return retval; } long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { struct inode *inode = file_inode(filp); long old_block, new_block; int result; if (file_permission(filp, MAY_READ) != 0) { udf_debug("no permission to access inode %lu\n", inode->i_ino); return -EPERM; } if (!arg && ((cmd == UDF_GETVOLIDENT) || (cmd == UDF_GETEASIZE) || (cmd == UDF_RELOCATE_BLOCKS) || (cmd == UDF_GETEABLOCK))) { udf_debug("invalid argument to udf_ioctl\n"); return -EINVAL; } switch (cmd) { case UDF_GETVOLIDENT: if (copy_to_user((char __user *)arg, UDF_SB(inode->i_sb)->s_volume_ident, 32)) return -EFAULT; return 0; case UDF_RELOCATE_BLOCKS: if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (get_user(old_block, (long __user *)arg)) return -EFAULT; result = udf_relocate_blocks(inode->i_sb, old_block, &new_block); if (result == 0) result = put_user(new_block, (long __user *)arg); return result; case UDF_GETEASIZE: return put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg); case UDF_GETEABLOCK: return copy_to_user((char __user *)arg, UDF_I(inode)->i_data, UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0; default: return -ENOIOCTLCMD; } return 0; } static int udf_release_file(struct inode *inode, struct file *filp) { if (filp->f_mode & FMODE_WRITE && atomic_read(&inode->i_writecount) == 1) { /* * Grab i_mutex to avoid races with writes changing i_size * while we are running. */ inode_lock(inode); down_write(&UDF_I(inode)->i_data_sem); udf_discard_prealloc(inode); udf_truncate_tail_extent(inode); up_write(&UDF_I(inode)->i_data_sem); inode_unlock(inode); } return 0; } static int udf_file_mmap(struct file *file, struct vm_area_struct *vma) { file_accessed(file); vma->vm_ops = &udf_file_vm_ops; return 0; } const struct file_operations udf_file_operations = { .read_iter = generic_file_read_iter, .unlocked_ioctl = udf_ioctl, .open = generic_file_open, .mmap = udf_file_mmap, .write_iter = udf_file_write_iter, .release = udf_release_file, .fsync = generic_file_fsync, .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .llseek = generic_file_llseek, }; static int udf_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *attr) { struct inode *inode = d_inode(dentry); struct super_block *sb = inode->i_sb; int error; error = setattr_prepare(&nop_mnt_idmap, dentry, attr); if (error) return error; if ((attr->ia_valid & ATTR_UID) && UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET) && !uid_eq(attr->ia_uid, UDF_SB(sb)->s_uid)) return -EPERM; if ((attr->ia_valid & ATTR_GID) && UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET) && !gid_eq(attr->ia_gid, UDF_SB(sb)->s_gid)) return -EPERM; if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size != i_size_read(inode)) { error = udf_setsize(inode, attr->ia_size); if (error) return error; } if (attr->ia_valid & ATTR_MODE) udf_update_extra_perms(inode, attr->ia_mode); setattr_copy(&nop_mnt_idmap, inode, attr); mark_inode_dirty(inode); return 0; } const struct inode_operations udf_file_inode_operations = { .setattr = udf_setattr, };