1 /* 2 * file.c 3 * 4 * PURPOSE 5 * File handling routines for the OSTA-UDF(tm) filesystem. 6 * 7 * CONTACTS 8 * E-mail regarding any portion of the Linux UDF file system should be 9 * directed to the development team mailing list (run by majordomo): 10 * linux_udf@hpesjro.fc.hp.com 11 * 12 * COPYRIGHT 13 * This file is distributed under the terms of the GNU General Public 14 * License (GPL). Copies of the GPL can be obtained from: 15 * ftp://prep.ai.mit.edu/pub/gnu/GPL 16 * Each contributing author retains all rights to their own work. 17 * 18 * (C) 1998-1999 Dave Boynton 19 * (C) 1998-2004 Ben Fennema 20 * (C) 1999-2000 Stelias Computing Inc 21 * 22 * HISTORY 23 * 24 * 10/02/98 dgb Attempt to integrate into udf.o 25 * 10/07/98 Switched to using generic_readpage, etc., like isofs 26 * And it works! 27 * 12/06/98 blf Added udf_file_read. uses generic_file_read for all cases but 28 * ICBTAG_FLAG_AD_IN_ICB. 29 * 04/06/99 64 bit file handling on 32 bit systems taken from ext2 file.c 30 * 05/12/99 Preliminary file write support 31 */ 32 33 #include "udfdecl.h" 34 #include <linux/fs.h> 35 #include <linux/udf_fs.h> 36 #include <asm/uaccess.h> 37 #include <linux/kernel.h> 38 #include <linux/string.h> /* memset */ 39 #include <linux/errno.h> 40 #include <linux/smp_lock.h> 41 #include <linux/pagemap.h> 42 #include <linux/buffer_head.h> 43 44 #include "udf_i.h" 45 #include "udf_sb.h" 46 47 static int udf_adinicb_readpage(struct file *file, struct page * page) 48 { 49 struct inode *inode = page->mapping->host; 50 char *kaddr; 51 52 if (!PageLocked(page)) 53 PAGE_BUG(page); 54 55 kaddr = kmap(page); 56 memset(kaddr, 0, PAGE_CACHE_SIZE); 57 memcpy(kaddr, UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), inode->i_size); 58 flush_dcache_page(page); 59 SetPageUptodate(page); 60 kunmap(page); 61 unlock_page(page); 62 return 0; 63 } 64 65 static int udf_adinicb_writepage(struct page *page, struct writeback_control *wbc) 66 { 67 struct inode *inode = page->mapping->host; 68 char *kaddr; 69 70 if (!PageLocked(page)) 71 PAGE_BUG(page); 72 73 kaddr = kmap(page); 74 memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), kaddr, inode->i_size); 75 mark_inode_dirty(inode); 76 SetPageUptodate(page); 77 kunmap(page); 78 unlock_page(page); 79 return 0; 80 } 81 82 static int udf_adinicb_prepare_write(struct file *file, struct page *page, unsigned offset, unsigned to) 83 { 84 kmap(page); 85 return 0; 86 } 87 88 static int udf_adinicb_commit_write(struct file *file, struct page *page, unsigned offset, unsigned to) 89 { 90 struct inode *inode = page->mapping->host; 91 char *kaddr = page_address(page); 92 93 memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode) + offset, 94 kaddr + offset, to - offset); 95 mark_inode_dirty(inode); 96 SetPageUptodate(page); 97 kunmap(page); 98 /* only one page here */ 99 if (to > inode->i_size) 100 inode->i_size = to; 101 return 0; 102 } 103 104 struct address_space_operations udf_adinicb_aops = { 105 .readpage = udf_adinicb_readpage, 106 .writepage = udf_adinicb_writepage, 107 .sync_page = block_sync_page, 108 .prepare_write = udf_adinicb_prepare_write, 109 .commit_write = udf_adinicb_commit_write, 110 }; 111 112 static ssize_t udf_file_write(struct file * file, const char __user * buf, 113 size_t count, loff_t *ppos) 114 { 115 ssize_t retval; 116 struct inode *inode = file->f_dentry->d_inode; 117 int err, pos; 118 119 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB) 120 { 121 if (file->f_flags & O_APPEND) 122 pos = inode->i_size; 123 else 124 pos = *ppos; 125 126 if (inode->i_sb->s_blocksize < (udf_file_entry_alloc_offset(inode) + 127 pos + count)) 128 { 129 udf_expand_file_adinicb(inode, pos + count, &err); 130 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB) 131 { 132 udf_debug("udf_expand_adinicb: err=%d\n", err); 133 return err; 134 } 135 } 136 else 137 { 138 if (pos + count > inode->i_size) 139 UDF_I_LENALLOC(inode) = pos + count; 140 else 141 UDF_I_LENALLOC(inode) = inode->i_size; 142 } 143 } 144 145 retval = generic_file_write(file, buf, count, ppos); 146 147 if (retval > 0) 148 mark_inode_dirty(inode); 149 return retval; 150 } 151 152 /* 153 * udf_ioctl 154 * 155 * PURPOSE 156 * Issue an ioctl. 157 * 158 * DESCRIPTION 159 * Optional - sys_ioctl() will return -ENOTTY if this routine is not 160 * available, and the ioctl cannot be handled without filesystem help. 161 * 162 * sys_ioctl() handles these ioctls that apply only to regular files: 163 * FIBMAP [requires udf_block_map()], FIGETBSZ, FIONREAD 164 * These ioctls are also handled by sys_ioctl(): 165 * FIOCLEX, FIONCLEX, FIONBIO, FIOASYNC 166 * All other ioctls are passed to the filesystem. 167 * 168 * Refer to sys_ioctl() in fs/ioctl.c 169 * sys_ioctl() -> . 170 * 171 * PRE-CONDITIONS 172 * inode Pointer to inode that ioctl was issued on. 173 * filp Pointer to file that ioctl was issued on. 174 * cmd The ioctl command. 175 * arg The ioctl argument [can be interpreted as a 176 * user-space pointer if desired]. 177 * 178 * POST-CONDITIONS 179 * <return> Success (>=0) or an error code (<=0) that 180 * sys_ioctl() will return. 181 * 182 * HISTORY 183 * July 1, 1997 - Andrew E. Mileski 184 * Written, tested, and released. 185 */ 186 int udf_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, 187 unsigned long arg) 188 { 189 int result = -EINVAL; 190 191 if ( permission(inode, MAY_READ, NULL) != 0 ) 192 { 193 udf_debug("no permission to access inode %lu\n", 194 inode->i_ino); 195 return -EPERM; 196 } 197 198 if ( !arg ) 199 { 200 udf_debug("invalid argument to udf_ioctl\n"); 201 return -EINVAL; 202 } 203 204 switch (cmd) 205 { 206 case UDF_GETVOLIDENT: 207 return copy_to_user((char __user *)arg, 208 UDF_SB_VOLIDENT(inode->i_sb), 32) ? -EFAULT : 0; 209 case UDF_RELOCATE_BLOCKS: 210 { 211 long old, new; 212 213 if (!capable(CAP_SYS_ADMIN)) return -EACCES; 214 if (get_user(old, (long __user *)arg)) return -EFAULT; 215 if ((result = udf_relocate_blocks(inode->i_sb, 216 old, &new)) == 0) 217 result = put_user(new, (long __user *)arg); 218 219 return result; 220 } 221 case UDF_GETEASIZE: 222 result = put_user(UDF_I_LENEATTR(inode), (int __user *)arg); 223 break; 224 225 case UDF_GETEABLOCK: 226 result = copy_to_user((char __user *)arg, UDF_I_DATA(inode), 227 UDF_I_LENEATTR(inode)) ? -EFAULT : 0; 228 break; 229 } 230 231 return result; 232 } 233 234 /* 235 * udf_release_file 236 * 237 * PURPOSE 238 * Called when all references to the file are closed 239 * 240 * DESCRIPTION 241 * Discard prealloced blocks 242 * 243 * HISTORY 244 * 245 */ 246 static int udf_release_file(struct inode * inode, struct file * filp) 247 { 248 if (filp->f_mode & FMODE_WRITE) 249 { 250 lock_kernel(); 251 udf_discard_prealloc(inode); 252 unlock_kernel(); 253 } 254 return 0; 255 } 256 257 struct file_operations udf_file_operations = { 258 .read = generic_file_read, 259 .ioctl = udf_ioctl, 260 .open = generic_file_open, 261 .mmap = generic_file_mmap, 262 .write = udf_file_write, 263 .release = udf_release_file, 264 .fsync = udf_fsync_file, 265 .sendfile = generic_file_sendfile, 266 }; 267 268 struct inode_operations udf_file_inode_operations = { 269 .truncate = udf_truncate, 270 }; 271