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/capability.h> 35 #include <linux/errno.h> 36 #include <linux/smp_lock.h> 37 #include <linux/pagemap.h> 38 #include <linux/buffer_head.h> 39 #include <linux/aio.h> 40 41 #include "udf_i.h" 42 #include "udf_sb.h" 43 44 static int udf_adinicb_readpage(struct file *file, struct page * page) 45 { 46 struct inode *inode = page->mapping->host; 47 char *kaddr; 48 49 BUG_ON(!PageLocked(page)); 50 51 kaddr = kmap(page); 52 memset(kaddr, 0, PAGE_CACHE_SIZE); 53 memcpy(kaddr, UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), inode->i_size); 54 flush_dcache_page(page); 55 SetPageUptodate(page); 56 kunmap(page); 57 unlock_page(page); 58 return 0; 59 } 60 61 static int udf_adinicb_writepage(struct page *page, struct writeback_control *wbc) 62 { 63 struct inode *inode = page->mapping->host; 64 char *kaddr; 65 66 BUG_ON(!PageLocked(page)); 67 68 kaddr = kmap(page); 69 memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), kaddr, inode->i_size); 70 mark_inode_dirty(inode); 71 SetPageUptodate(page); 72 kunmap(page); 73 unlock_page(page); 74 return 0; 75 } 76 77 static int udf_adinicb_prepare_write(struct file *file, struct page *page, unsigned offset, unsigned to) 78 { 79 kmap(page); 80 return 0; 81 } 82 83 static int udf_adinicb_commit_write(struct file *file, struct page *page, unsigned offset, unsigned to) 84 { 85 struct inode *inode = page->mapping->host; 86 char *kaddr = page_address(page); 87 88 memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode) + offset, 89 kaddr + offset, to - offset); 90 mark_inode_dirty(inode); 91 SetPageUptodate(page); 92 kunmap(page); 93 /* only one page here */ 94 if (to > inode->i_size) 95 inode->i_size = to; 96 return 0; 97 } 98 99 const struct address_space_operations udf_adinicb_aops = { 100 .readpage = udf_adinicb_readpage, 101 .writepage = udf_adinicb_writepage, 102 .sync_page = block_sync_page, 103 .prepare_write = udf_adinicb_prepare_write, 104 .commit_write = udf_adinicb_commit_write, 105 }; 106 107 static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 108 unsigned long nr_segs, loff_t ppos) 109 { 110 ssize_t retval; 111 struct file *file = iocb->ki_filp; 112 struct inode *inode = file->f_path.dentry->d_inode; 113 int err, pos; 114 size_t count = iocb->ki_left; 115 116 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB) 117 { 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 < (udf_file_entry_alloc_offset(inode) + 124 pos + count)) 125 { 126 udf_expand_file_adinicb(inode, pos + count, &err); 127 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB) 128 { 129 udf_debug("udf_expand_adinicb: err=%d\n", err); 130 return err; 131 } 132 } 133 else 134 { 135 if (pos + count > inode->i_size) 136 UDF_I_LENALLOC(inode) = pos + count; 137 else 138 UDF_I_LENALLOC(inode) = inode->i_size; 139 } 140 } 141 142 retval = generic_file_aio_write(iocb, iov, nr_segs, ppos); 143 144 if (retval > 0) 145 mark_inode_dirty(inode); 146 return retval; 147 } 148 149 /* 150 * udf_ioctl 151 * 152 * PURPOSE 153 * Issue an ioctl. 154 * 155 * DESCRIPTION 156 * Optional - sys_ioctl() will return -ENOTTY if this routine is not 157 * available, and the ioctl cannot be handled without filesystem help. 158 * 159 * sys_ioctl() handles these ioctls that apply only to regular files: 160 * FIBMAP [requires udf_block_map()], FIGETBSZ, FIONREAD 161 * These ioctls are also handled by sys_ioctl(): 162 * FIOCLEX, FIONCLEX, FIONBIO, FIOASYNC 163 * All other ioctls are passed to the filesystem. 164 * 165 * Refer to sys_ioctl() in fs/ioctl.c 166 * sys_ioctl() -> . 167 * 168 * PRE-CONDITIONS 169 * inode Pointer to inode that ioctl was issued on. 170 * filp Pointer to file that ioctl was issued on. 171 * cmd The ioctl command. 172 * arg The ioctl argument [can be interpreted as a 173 * user-space pointer if desired]. 174 * 175 * POST-CONDITIONS 176 * <return> Success (>=0) or an error code (<=0) that 177 * sys_ioctl() will return. 178 * 179 * HISTORY 180 * July 1, 1997 - Andrew E. Mileski 181 * Written, tested, and released. 182 */ 183 int udf_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, 184 unsigned long arg) 185 { 186 int result = -EINVAL; 187 188 if ( file_permission(filp, MAY_READ) != 0 ) 189 { 190 udf_debug("no permission to access inode %lu\n", 191 inode->i_ino); 192 return -EPERM; 193 } 194 195 if ( !arg ) 196 { 197 udf_debug("invalid argument to udf_ioctl\n"); 198 return -EINVAL; 199 } 200 201 switch (cmd) 202 { 203 case UDF_GETVOLIDENT: 204 return copy_to_user((char __user *)arg, 205 UDF_SB_VOLIDENT(inode->i_sb), 32) ? -EFAULT : 0; 206 case UDF_RELOCATE_BLOCKS: 207 { 208 long old, new; 209 210 if (!capable(CAP_SYS_ADMIN)) return -EACCES; 211 if (get_user(old, (long __user *)arg)) return -EFAULT; 212 if ((result = udf_relocate_blocks(inode->i_sb, 213 old, &new)) == 0) 214 result = put_user(new, (long __user *)arg); 215 216 return result; 217 } 218 case UDF_GETEASIZE: 219 result = put_user(UDF_I_LENEATTR(inode), (int __user *)arg); 220 break; 221 222 case UDF_GETEABLOCK: 223 result = copy_to_user((char __user *)arg, UDF_I_DATA(inode), 224 UDF_I_LENEATTR(inode)) ? -EFAULT : 0; 225 break; 226 } 227 228 return result; 229 } 230 231 /* 232 * udf_release_file 233 * 234 * PURPOSE 235 * Called when all references to the file are closed 236 * 237 * DESCRIPTION 238 * Discard prealloced blocks 239 * 240 * HISTORY 241 * 242 */ 243 static int udf_release_file(struct inode * inode, struct file * filp) 244 { 245 if (filp->f_mode & FMODE_WRITE) 246 { 247 lock_kernel(); 248 udf_discard_prealloc(inode); 249 unlock_kernel(); 250 } 251 return 0; 252 } 253 254 const struct file_operations udf_file_operations = { 255 .read = do_sync_read, 256 .aio_read = generic_file_aio_read, 257 .ioctl = udf_ioctl, 258 .open = generic_file_open, 259 .mmap = generic_file_mmap, 260 .write = do_sync_write, 261 .aio_write = udf_file_aio_write, 262 .release = udf_release_file, 263 .fsync = udf_fsync_file, 264 .sendfile = generic_file_sendfile, 265 }; 266 267 const struct inode_operations udf_file_inode_operations = { 268 .truncate = udf_truncate, 269 }; 270