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