1 /* 2 * file.c 3 * 4 * PURPOSE 5 * File handling routines for the OSTA-UDF(tm) filesystem. 6 * 7 * COPYRIGHT 8 * This file is distributed under the terms of the GNU General Public 9 * License (GPL). Copies of the GPL can be obtained from: 10 * ftp://prep.ai.mit.edu/pub/gnu/GPL 11 * Each contributing author retains all rights to their own work. 12 * 13 * (C) 1998-1999 Dave Boynton 14 * (C) 1998-2004 Ben Fennema 15 * (C) 1999-2000 Stelias Computing Inc 16 * 17 * HISTORY 18 * 19 * 10/02/98 dgb Attempt to integrate into udf.o 20 * 10/07/98 Switched to using generic_readpage, etc., like isofs 21 * And it works! 22 * 12/06/98 blf Added udf_file_read. uses generic_file_read for all cases but 23 * ICBTAG_FLAG_AD_IN_ICB. 24 * 04/06/99 64 bit file handling on 32 bit systems taken from ext2 file.c 25 * 05/12/99 Preliminary file write support 26 */ 27 28 #include "udfdecl.h" 29 #include <linux/fs.h> 30 #include <asm/uaccess.h> 31 #include <linux/kernel.h> 32 #include <linux/string.h> /* memset */ 33 #include <linux/capability.h> 34 #include <linux/errno.h> 35 #include <linux/pagemap.h> 36 #include <linux/buffer_head.h> 37 #include <linux/aio.h> 38 39 #include "udf_i.h" 40 #include "udf_sb.h" 41 42 static int udf_adinicb_readpage(struct file *file, struct page *page) 43 { 44 struct inode *inode = page->mapping->host; 45 char *kaddr; 46 struct udf_inode_info *iinfo = UDF_I(inode); 47 48 BUG_ON(!PageLocked(page)); 49 50 kaddr = kmap(page); 51 memset(kaddr, 0, PAGE_CACHE_SIZE); 52 memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size); 53 flush_dcache_page(page); 54 SetPageUptodate(page); 55 kunmap(page); 56 unlock_page(page); 57 58 return 0; 59 } 60 61 static int udf_adinicb_writepage(struct page *page, 62 struct writeback_control *wbc) 63 { 64 struct inode *inode = page->mapping->host; 65 char *kaddr; 66 struct udf_inode_info *iinfo = UDF_I(inode); 67 68 BUG_ON(!PageLocked(page)); 69 70 kaddr = kmap(page); 71 memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size); 72 mark_inode_dirty(inode); 73 SetPageUptodate(page); 74 kunmap(page); 75 unlock_page(page); 76 77 return 0; 78 } 79 80 static int udf_adinicb_write_end(struct file *file, 81 struct address_space *mapping, 82 loff_t pos, unsigned len, unsigned copied, 83 struct page *page, void *fsdata) 84 { 85 struct inode *inode = mapping->host; 86 unsigned offset = pos & (PAGE_CACHE_SIZE - 1); 87 char *kaddr; 88 struct udf_inode_info *iinfo = UDF_I(inode); 89 90 kaddr = kmap_atomic(page, KM_USER0); 91 memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr + offset, 92 kaddr + offset, copied); 93 kunmap_atomic(kaddr, KM_USER0); 94 95 return simple_write_end(file, mapping, pos, len, copied, page, fsdata); 96 } 97 98 const struct address_space_operations udf_adinicb_aops = { 99 .readpage = udf_adinicb_readpage, 100 .writepage = udf_adinicb_writepage, 101 .sync_page = block_sync_page, 102 .write_begin = simple_write_begin, 103 .write_end = udf_adinicb_write_end, 104 }; 105 106 static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 107 unsigned long nr_segs, loff_t ppos) 108 { 109 ssize_t retval; 110 struct file *file = iocb->ki_filp; 111 struct inode *inode = file->f_path.dentry->d_inode; 112 int err, pos; 113 size_t count = iocb->ki_left; 114 struct udf_inode_info *iinfo = UDF_I(inode); 115 116 down_write(&iinfo->i_data_sem); 117 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { 118 if (file->f_flags & O_APPEND) 119 pos = inode->i_size; 120 else 121 pos = ppos; 122 123 if (inode->i_sb->s_blocksize < 124 (udf_file_entry_alloc_offset(inode) + 125 pos + count)) { 126 udf_expand_file_adinicb(inode, pos + count, &err); 127 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { 128 udf_debug("udf_expand_adinicb: err=%d\n", err); 129 up_write(&iinfo->i_data_sem); 130 return err; 131 } 132 } else { 133 if (pos + count > inode->i_size) 134 iinfo->i_lenAlloc = pos + count; 135 else 136 iinfo->i_lenAlloc = inode->i_size; 137 } 138 } 139 up_write(&iinfo->i_data_sem); 140 141 retval = generic_file_aio_write(iocb, iov, nr_segs, ppos); 142 if (retval > 0) 143 mark_inode_dirty(inode); 144 145 return retval; 146 } 147 148 long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 149 { 150 struct inode *inode = filp->f_dentry->d_inode; 151 long old_block, new_block; 152 int result = -EINVAL; 153 154 if (file_permission(filp, MAY_READ) != 0) { 155 udf_debug("no permission to access inode %lu\n", inode->i_ino); 156 result = -EPERM; 157 goto out; 158 } 159 160 if (!arg) { 161 udf_debug("invalid argument to udf_ioctl\n"); 162 result = -EINVAL; 163 goto out; 164 } 165 166 switch (cmd) { 167 case UDF_GETVOLIDENT: 168 if (copy_to_user((char __user *)arg, 169 UDF_SB(inode->i_sb)->s_volume_ident, 32)) 170 result = -EFAULT; 171 else 172 result = 0; 173 goto out; 174 case UDF_RELOCATE_BLOCKS: 175 if (!capable(CAP_SYS_ADMIN)) { 176 result = -EACCES; 177 goto out; 178 } 179 if (get_user(old_block, (long __user *)arg)) { 180 result = -EFAULT; 181 goto out; 182 } 183 result = udf_relocate_blocks(inode->i_sb, 184 old_block, &new_block); 185 if (result == 0) 186 result = put_user(new_block, (long __user *)arg); 187 goto out; 188 case UDF_GETEASIZE: 189 result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg); 190 goto out; 191 case UDF_GETEABLOCK: 192 result = copy_to_user((char __user *)arg, 193 UDF_I(inode)->i_ext.i_data, 194 UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0; 195 goto out; 196 } 197 198 out: 199 return result; 200 } 201 202 static int udf_release_file(struct inode *inode, struct file *filp) 203 { 204 if (filp->f_mode & FMODE_WRITE) { 205 mutex_lock(&inode->i_mutex); 206 down_write(&UDF_I(inode)->i_data_sem); 207 udf_discard_prealloc(inode); 208 udf_truncate_tail_extent(inode); 209 up_write(&UDF_I(inode)->i_data_sem); 210 mutex_unlock(&inode->i_mutex); 211 } 212 return 0; 213 } 214 215 const struct file_operations udf_file_operations = { 216 .read = do_sync_read, 217 .aio_read = generic_file_aio_read, 218 .unlocked_ioctl = udf_ioctl, 219 .open = generic_file_open, 220 .mmap = generic_file_mmap, 221 .write = do_sync_write, 222 .aio_write = udf_file_aio_write, 223 .release = udf_release_file, 224 .fsync = generic_file_fsync, 225 .splice_read = generic_file_splice_read, 226 .llseek = generic_file_llseek, 227 }; 228 229 static int udf_setattr(struct dentry *dentry, struct iattr *attr) 230 { 231 struct inode *inode = dentry->d_inode; 232 int error; 233 234 error = inode_change_ok(inode, attr); 235 if (error) 236 return error; 237 238 if ((attr->ia_valid & ATTR_SIZE) && 239 attr->ia_size != i_size_read(inode)) { 240 error = vmtruncate(inode, attr->ia_size); 241 if (error) 242 return error; 243 } 244 245 setattr_copy(inode, attr); 246 mark_inode_dirty(inode); 247 return 0; 248 } 249 250 const struct inode_operations udf_file_inode_operations = { 251 .setattr = udf_setattr, 252 .truncate = udf_truncate, 253 }; 254