--- /dev/null
+/*
+ * 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 = inode_change_ok(inode, 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,
+};
Code Review / kvmfornfv.git / blobdiff