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); 91 memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr + offset, 92 kaddr + offset, copied); 93 kunmap_atomic(kaddr); 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 .write_begin = simple_write_begin, 102 .write_end = udf_adinicb_write_end, 103 }; 104 105 static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 106 unsigned long nr_segs, loff_t ppos) 107 { 108 ssize_t retval; 109 struct file *file = iocb->ki_filp; 110 struct inode *inode = file->f_path.dentry->d_inode; 111 int err, pos; 112 size_t count = iocb->ki_left; 113 struct udf_inode_info *iinfo = UDF_I(inode); 114 115 down_write(&iinfo->i_data_sem); 116 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { 117 if (file->f_flags & O_APPEND) 118 pos = inode->i_size; 119 else 120 pos = ppos; 121 122 if (inode->i_sb->s_blocksize < 123 (udf_file_entry_alloc_offset(inode) + 124 pos + count)) { 125 err = udf_expand_file_adinicb(inode); 126 if (err) { 127 udf_debug("udf_expand_adinicb: err=%d\n", err); 128 return err; 129 } 130 } else { 131 if (pos + count > inode->i_size) 132 iinfo->i_lenAlloc = pos + count; 133 else 134 iinfo->i_lenAlloc = inode->i_size; 135 up_write(&iinfo->i_data_sem); 136 } 137 } else 138 up_write(&iinfo->i_data_sem); 139 140 retval = generic_file_aio_write(iocb, iov, nr_segs, ppos); 141 if (retval > 0) 142 mark_inode_dirty(inode); 143 144 return retval; 145 } 146 147 long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 148 { 149 struct inode *inode = filp->f_dentry->d_inode; 150 long old_block, new_block; 151 int result = -EINVAL; 152 153 if (inode_permission(inode, MAY_READ) != 0) { 154 udf_debug("no permission to access inode %lu\n", inode->i_ino); 155 result = -EPERM; 156 goto out; 157 } 158 159 if (!arg) { 160 udf_debug("invalid argument to udf_ioctl\n"); 161 result = -EINVAL; 162 goto out; 163 } 164 165 switch (cmd) { 166 case UDF_GETVOLIDENT: 167 if (copy_to_user((char __user *)arg, 168 UDF_SB(inode->i_sb)->s_volume_ident, 32)) 169 result = -EFAULT; 170 else 171 result = 0; 172 goto out; 173 case UDF_RELOCATE_BLOCKS: 174 if (!capable(CAP_SYS_ADMIN)) { 175 result = -EACCES; 176 goto out; 177 } 178 if (get_user(old_block, (long __user *)arg)) { 179 result = -EFAULT; 180 goto out; 181 } 182 result = udf_relocate_blocks(inode->i_sb, 183 old_block, &new_block); 184 if (result == 0) 185 result = put_user(new_block, (long __user *)arg); 186 goto out; 187 case UDF_GETEASIZE: 188 result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg); 189 goto out; 190 case UDF_GETEABLOCK: 191 result = copy_to_user((char __user *)arg, 192 UDF_I(inode)->i_ext.i_data, 193 UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0; 194 goto out; 195 } 196 197 out: 198 return result; 199 } 200 201 static int udf_release_file(struct inode *inode, struct file *filp) 202 { 203 if (filp->f_mode & FMODE_WRITE) { 204 down_write(&UDF_I(inode)->i_data_sem); 205 udf_discard_prealloc(inode); 206 udf_truncate_tail_extent(inode); 207 up_write(&UDF_I(inode)->i_data_sem); 208 } 209 return 0; 210 } 211 212 const struct file_operations udf_file_operations = { 213 .read = do_sync_read, 214 .aio_read = generic_file_aio_read, 215 .unlocked_ioctl = udf_ioctl, 216 .open = generic_file_open, 217 .mmap = generic_file_mmap, 218 .write = do_sync_write, 219 .aio_write = udf_file_aio_write, 220 .release = udf_release_file, 221 .fsync = generic_file_fsync, 222 .splice_read = generic_file_splice_read, 223 .llseek = generic_file_llseek, 224 }; 225 226 static int udf_setattr(struct dentry *dentry, struct iattr *attr) 227 { 228 struct inode *inode = dentry->d_inode; 229 int error; 230 231 error = inode_change_ok(inode, attr); 232 if (error) 233 return error; 234 235 if ((attr->ia_valid & ATTR_SIZE) && 236 attr->ia_size != i_size_read(inode)) { 237 error = udf_setsize(inode, attr->ia_size); 238 if (error) 239 return error; 240 } 241 242 setattr_copy(inode, attr); 243 mark_inode_dirty(inode); 244 return 0; 245 } 246 247 const struct inode_operations udf_file_inode_operations = { 248 .setattr = udf_setattr, 249 }; 250