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 <linux/udf_fs.h> 31 #include <asm/uaccess.h> 32 #include <linux/kernel.h> 33 #include <linux/string.h> /* memset */ 34 #include <linux/errno.h> 35 #include <linux/smp_lock.h> 36 #include <linux/pagemap.h> 37 #include <linux/buffer_head.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 47 BUG_ON(!PageLocked(page)); 48 49 kaddr = kmap(page); 50 memset(kaddr, 0, PAGE_CACHE_SIZE); 51 memcpy(kaddr, UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), inode->i_size); 52 flush_dcache_page(page); 53 SetPageUptodate(page); 54 kunmap(page); 55 unlock_page(page); 56 return 0; 57 } 58 59 static int udf_adinicb_writepage(struct page *page, struct writeback_control *wbc) 60 { 61 struct inode *inode = page->mapping->host; 62 char *kaddr; 63 64 BUG_ON(!PageLocked(page)); 65 66 kaddr = kmap(page); 67 memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), kaddr, inode->i_size); 68 mark_inode_dirty(inode); 69 SetPageUptodate(page); 70 kunmap(page); 71 unlock_page(page); 72 return 0; 73 } 74 75 static int udf_adinicb_prepare_write(struct file *file, struct page *page, unsigned offset, unsigned to) 76 { 77 kmap(page); 78 return 0; 79 } 80 81 static int udf_adinicb_commit_write(struct file *file, struct page *page, unsigned offset, unsigned to) 82 { 83 struct inode *inode = page->mapping->host; 84 char *kaddr = page_address(page); 85 86 memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode) + offset, 87 kaddr + offset, to - offset); 88 mark_inode_dirty(inode); 89 SetPageUptodate(page); 90 kunmap(page); 91 /* only one page here */ 92 if (to > inode->i_size) 93 inode->i_size = to; 94 return 0; 95 } 96 97 struct address_space_operations udf_adinicb_aops = { 98 .readpage = udf_adinicb_readpage, 99 .writepage = udf_adinicb_writepage, 100 .sync_page = block_sync_page, 101 .prepare_write = udf_adinicb_prepare_write, 102 .commit_write = udf_adinicb_commit_write, 103 }; 104 105 static ssize_t udf_file_write(struct file * file, const char __user * buf, 106 size_t count, loff_t *ppos) 107 { 108 ssize_t retval; 109 struct inode *inode = file->f_dentry->d_inode; 110 int err, pos; 111 112 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB) 113 { 114 if (file->f_flags & O_APPEND) 115 pos = inode->i_size; 116 else 117 pos = *ppos; 118 119 if (inode->i_sb->s_blocksize < (udf_file_entry_alloc_offset(inode) + 120 pos + count)) 121 { 122 udf_expand_file_adinicb(inode, pos + count, &err); 123 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB) 124 { 125 udf_debug("udf_expand_adinicb: err=%d\n", err); 126 return err; 127 } 128 } 129 else 130 { 131 if (pos + count > inode->i_size) 132 UDF_I_LENALLOC(inode) = pos + count; 133 else 134 UDF_I_LENALLOC(inode) = inode->i_size; 135 } 136 } 137 138 retval = generic_file_write(file, buf, count, ppos); 139 140 if (retval > 0) 141 mark_inode_dirty(inode); 142 return retval; 143 } 144 145 /* 146 * udf_ioctl 147 * 148 * PURPOSE 149 * Issue an ioctl. 150 * 151 * DESCRIPTION 152 * Optional - sys_ioctl() will return -ENOTTY if this routine is not 153 * available, and the ioctl cannot be handled without filesystem help. 154 * 155 * sys_ioctl() handles these ioctls that apply only to regular files: 156 * FIBMAP [requires udf_block_map()], FIGETBSZ, FIONREAD 157 * These ioctls are also handled by sys_ioctl(): 158 * FIOCLEX, FIONCLEX, FIONBIO, FIOASYNC 159 * All other ioctls are passed to the filesystem. 160 * 161 * Refer to sys_ioctl() in fs/ioctl.c 162 * sys_ioctl() -> . 163 * 164 * PRE-CONDITIONS 165 * inode Pointer to inode that ioctl was issued on. 166 * filp Pointer to file that ioctl was issued on. 167 * cmd The ioctl command. 168 * arg The ioctl argument [can be interpreted as a 169 * user-space pointer if desired]. 170 * 171 * POST-CONDITIONS 172 * <return> Success (>=0) or an error code (<=0) that 173 * sys_ioctl() will return. 174 * 175 * HISTORY 176 * July 1, 1997 - Andrew E. Mileski 177 * Written, tested, and released. 178 */ 179 int udf_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, 180 unsigned long arg) 181 { 182 int result = -EINVAL; 183 184 if ( file_permission(filp, MAY_READ) != 0 ) 185 { 186 udf_debug("no permission to access inode %lu\n", 187 inode->i_ino); 188 return -EPERM; 189 } 190 191 if ( !arg ) 192 { 193 udf_debug("invalid argument to udf_ioctl\n"); 194 return -EINVAL; 195 } 196 197 switch (cmd) 198 { 199 case UDF_GETVOLIDENT: 200 return copy_to_user((char __user *)arg, 201 UDF_SB_VOLIDENT(inode->i_sb), 32) ? -EFAULT : 0; 202 case UDF_RELOCATE_BLOCKS: 203 { 204 long old, new; 205 206 if (!capable(CAP_SYS_ADMIN)) return -EACCES; 207 if (get_user(old, (long __user *)arg)) return -EFAULT; 208 if ((result = udf_relocate_blocks(inode->i_sb, 209 old, &new)) == 0) 210 result = put_user(new, (long __user *)arg); 211 212 return result; 213 } 214 case UDF_GETEASIZE: 215 result = put_user(UDF_I_LENEATTR(inode), (int __user *)arg); 216 break; 217 218 case UDF_GETEABLOCK: 219 result = copy_to_user((char __user *)arg, UDF_I_DATA(inode), 220 UDF_I_LENEATTR(inode)) ? -EFAULT : 0; 221 break; 222 } 223 224 return result; 225 } 226 227 /* 228 * udf_release_file 229 * 230 * PURPOSE 231 * Called when all references to the file are closed 232 * 233 * DESCRIPTION 234 * Discard prealloced blocks 235 * 236 * HISTORY 237 * 238 */ 239 static int udf_release_file(struct inode * inode, struct file * filp) 240 { 241 if (filp->f_mode & FMODE_WRITE) 242 { 243 lock_kernel(); 244 udf_discard_prealloc(inode); 245 unlock_kernel(); 246 } 247 return 0; 248 } 249 250 struct file_operations udf_file_operations = { 251 .read = generic_file_read, 252 .ioctl = udf_ioctl, 253 .open = generic_file_open, 254 .mmap = generic_file_mmap, 255 .write = udf_file_write, 256 .release = udf_release_file, 257 .fsync = udf_fsync_file, 258 .sendfile = generic_file_sendfile, 259 }; 260 261 struct inode_operations udf_file_inode_operations = { 262 .truncate = udf_truncate, 263 }; 264