| /* |
| * 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 <linux/fs.h> |
| #include <linux/uaccess.h> |
| #include <linux/kernel.h> |
| #include <linux/string.h> /* memset */ |
| #include <linux/capability.h> |
| #include <linux/errno.h> |
| #include <linux/pagemap.h> |
| #include <linux/uio.h> |
| |
| #include "udf_i.h" |
| #include "udf_sb.h" |
| |
| static void __udf_adinicb_readpage(struct page *page) |
| { |
| struct inode *inode = page->mapping->host; |
| char *kaddr; |
| struct udf_inode_info *iinfo = UDF_I(inode); |
| |
| kaddr = kmap(page); |
| memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size); |
| memset(kaddr + inode->i_size, 0, PAGE_CACHE_SIZE - inode->i_size); |
| flush_dcache_page(page); |
| SetPageUptodate(page); |
| kunmap(page); |
| } |
| |
| static int udf_adinicb_readpage(struct file *file, struct page *page) |
| { |
| BUG_ON(!PageLocked(page)); |
| __udf_adinicb_readpage(page); |
| unlock_page(page); |
| |
| return 0; |
| } |
| |
| static int udf_adinicb_writepage(struct page *page, |
| struct writeback_control *wbc) |
| { |
| struct inode *inode = page->mapping->host; |
| char *kaddr; |
| struct udf_inode_info *iinfo = UDF_I(inode); |
| |
| BUG_ON(!PageLocked(page)); |
| |
| kaddr = kmap(page); |
| memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size); |
| mark_inode_dirty(inode); |
| SetPageUptodate(page); |
| kunmap(page); |
| unlock_page(page); |
| |
| return 0; |
| } |
| |
| static int udf_adinicb_write_begin(struct file *file, |
| struct address_space *mapping, loff_t pos, |
| unsigned len, unsigned flags, struct page **pagep, |
| void **fsdata) |
| { |
| struct page *page; |
| |
| if (WARN_ON_ONCE(pos >= PAGE_CACHE_SIZE)) |
| return -EIO; |
| page = grab_cache_page_write_begin(mapping, 0, flags); |
| if (!page) |
| return -ENOMEM; |
| *pagep = page; |
| |
| if (!PageUptodate(page) && len != PAGE_CACHE_SIZE) |
| __udf_adinicb_readpage(page); |
| return 0; |
| } |
| |
| static ssize_t udf_adinicb_direct_IO(struct kiocb *iocb, struct iov_iter *iter, |
| loff_t offset) |
| { |
| /* Fallback to buffered I/O. */ |
| return 0; |
| } |
| |
| const struct address_space_operations udf_adinicb_aops = { |
| .readpage = udf_adinicb_readpage, |
| .writepage = udf_adinicb_writepage, |
| .write_begin = udf_adinicb_write_begin, |
| .write_end = simple_write_end, |
| .direct_IO = udf_adinicb_direct_IO, |
| }; |
| |
| 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); |
| int err; |
| |
| mutex_lock(&inode->i_mutex); |
| |
| retval = generic_write_checks(iocb, from); |
| if (retval <= 0) |
| goto out; |
| |
| down_write(&iinfo->i_data_sem); |
| if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { |
| loff_t end = iocb->ki_pos + iov_iter_count(from); |
| |
| if (inode->i_sb->s_blocksize < |
| (udf_file_entry_alloc_offset(inode) + end)) { |
| err = udf_expand_file_adinicb(inode); |
| if (err) { |
| mutex_unlock(&inode->i_mutex); |
| udf_debug("udf_expand_adinicb: err=%d\n", err); |
| return err; |
| } |
| } else { |
| iinfo->i_lenAlloc = max(end, inode->i_size); |
| up_write(&iinfo->i_data_sem); |
| } |
| } else |
| up_write(&iinfo->i_data_sem); |
| |
| retval = __generic_file_write_iter(iocb, from); |
| out: |
| mutex_unlock(&inode->i_mutex); |
| |
| if (retval > 0) { |
| ssize_t err; |
| |
| mark_inode_dirty(inode); |
| err = generic_write_sync(file, iocb->ki_pos - retval, retval); |
| if (err < 0) |
| retval = err; |
| } |
| |
| 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 = -EINVAL; |
| |
| if (inode_permission(inode, MAY_READ) != 0) { |
| udf_debug("no permission to access inode %lu\n", inode->i_ino); |
| result = -EPERM; |
| goto out; |
| } |
| |
| if (!arg) { |
| udf_debug("invalid argument to udf_ioctl\n"); |
| result = -EINVAL; |
| goto out; |
| } |
| |
| switch (cmd) { |
| case UDF_GETVOLIDENT: |
| if (copy_to_user((char __user *)arg, |
| UDF_SB(inode->i_sb)->s_volume_ident, 32)) |
| result = -EFAULT; |
| else |
| result = 0; |
| goto out; |
| case UDF_RELOCATE_BLOCKS: |
| if (!capable(CAP_SYS_ADMIN)) { |
| result = -EPERM; |
| goto out; |
| } |
| if (get_user(old_block, (long __user *)arg)) { |
| result = -EFAULT; |
| goto out; |
| } |
| result = udf_relocate_blocks(inode->i_sb, |
| old_block, &new_block); |
| if (result == 0) |
| result = put_user(new_block, (long __user *)arg); |
| goto out; |
| case UDF_GETEASIZE: |
| result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg); |
| goto out; |
| case UDF_GETEABLOCK: |
| result = copy_to_user((char __user *)arg, |
| UDF_I(inode)->i_ext.i_data, |
| UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0; |
| goto out; |
| } |
| |
| out: |
| return result; |
| } |
| |
| 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. |
| */ |
| mutex_lock(&inode->i_mutex); |
| 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); |
| mutex_unlock(&inode->i_mutex); |
| } |
| return 0; |
| } |
| |
| const struct file_operations udf_file_operations = { |
| .read_iter = generic_file_read_iter, |
| .unlocked_ioctl = udf_ioctl, |
| .open = generic_file_open, |
| .mmap = generic_file_mmap, |
| .write_iter = udf_file_write_iter, |
| .release = udf_release_file, |
| .fsync = generic_file_fsync, |
| .splice_read = generic_file_splice_read, |
| .llseek = generic_file_llseek, |
| }; |
| |
| static int udf_setattr(struct dentry *dentry, struct iattr *attr) |
| { |
| struct inode *inode = d_inode(dentry); |
| int error; |
| |
| error = setattr_prepare(dentry, attr); |
| if (error) |
| return error; |
| |
| if ((attr->ia_valid & ATTR_SIZE) && |
| attr->ia_size != i_size_read(inode)) { |
| error = udf_setsize(inode, attr->ia_size); |
| if (error) |
| return error; |
| } |
| |
| setattr_copy(inode, attr); |
| mark_inode_dirty(inode); |
| return 0; |
| } |
| |
| const struct inode_operations udf_file_inode_operations = { |
| .setattr = udf_setattr, |
| }; |