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/smp_lock.h> 36 #include <linux/pagemap.h> 37 #include <linux/buffer_head.h> 38 #include <linux/aio.h> 39 40 #include "udf_i.h" 41 #include "udf_sb.h" 42 43 static int udf_adinicb_readpage(struct file *file, struct page *page) 44 { 45 struct inode *inode = page->mapping->host; 46 char *kaddr; 47 struct udf_inode_info *iinfo = UDF_I(inode); 48 49 BUG_ON(!PageLocked(page)); 50 51 kaddr = kmap(page); 52 memset(kaddr, 0, PAGE_CACHE_SIZE); 53 memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, 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, 63 struct writeback_control *wbc) 64 { 65 struct inode *inode = page->mapping->host; 66 char *kaddr; 67 struct udf_inode_info *iinfo = UDF_I(inode); 68 69 BUG_ON(!PageLocked(page)); 70 71 kaddr = kmap(page); 72 memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size); 73 mark_inode_dirty(inode); 74 SetPageUptodate(page); 75 kunmap(page); 76 unlock_page(page); 77 78 return 0; 79 } 80 81 static int udf_adinicb_write_end(struct file *file, 82 struct address_space *mapping, 83 loff_t pos, unsigned len, unsigned copied, 84 struct page *page, void *fsdata) 85 { 86 struct inode *inode = mapping->host; 87 unsigned offset = pos & (PAGE_CACHE_SIZE - 1); 88 char *kaddr; 89 struct udf_inode_info *iinfo = UDF_I(inode); 90 91 kaddr = kmap_atomic(page, KM_USER0); 92 memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr + offset, 93 kaddr + offset, copied); 94 kunmap_atomic(kaddr, KM_USER0); 95 96 return simple_write_end(file, mapping, pos, len, copied, page, fsdata); 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 .write_begin = simple_write_begin, 104 .write_end = udf_adinicb_write_end, 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 struct udf_inode_info *iinfo = UDF_I(inode); 116 117 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { 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 < 124 (udf_file_entry_alloc_offset(inode) + 125 pos + count)) { 126 udf_expand_file_adinicb(inode, pos + count, &err); 127 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { 128 udf_debug("udf_expand_adinicb: err=%d\n", err); 129 return err; 130 } 131 } else { 132 if (pos + count > inode->i_size) 133 iinfo->i_lenAlloc = pos + count; 134 else 135 iinfo->i_lenAlloc = inode->i_size; 136 } 137 } 138 139 retval = generic_file_aio_write(iocb, iov, nr_segs, ppos); 140 if (retval > 0) 141 mark_inode_dirty(inode); 142 143 return retval; 144 } 145 146 int udf_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, 147 unsigned long arg) 148 { 149 long old_block, new_block; 150 int result = -EINVAL; 151 152 if (file_permission(filp, MAY_READ) != 0) { 153 udf_debug("no permission to access inode %lu\n", 154 inode->i_ino); 155 return -EPERM; 156 } 157 158 if (!arg) { 159 udf_debug("invalid argument to udf_ioctl\n"); 160 return -EINVAL; 161 } 162 163 switch (cmd) { 164 case UDF_GETVOLIDENT: 165 if (copy_to_user((char __user *)arg, 166 UDF_SB(inode->i_sb)->s_volume_ident, 32)) 167 return -EFAULT; 168 else 169 return 0; 170 case UDF_RELOCATE_BLOCKS: 171 if (!capable(CAP_SYS_ADMIN)) 172 return -EACCES; 173 if (get_user(old_block, (long __user *)arg)) 174 return -EFAULT; 175 result = udf_relocate_blocks(inode->i_sb, 176 old_block, &new_block); 177 if (result == 0) 178 result = put_user(new_block, (long __user *)arg); 179 return result; 180 case UDF_GETEASIZE: 181 result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg); 182 break; 183 case UDF_GETEABLOCK: 184 result = copy_to_user((char __user *)arg, 185 UDF_I(inode)->i_ext.i_data, 186 UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0; 187 break; 188 } 189 190 return result; 191 } 192 193 static int udf_release_file(struct inode *inode, struct file *filp) 194 { 195 if (filp->f_mode & FMODE_WRITE) { 196 lock_kernel(); 197 udf_discard_prealloc(inode); 198 unlock_kernel(); 199 } 200 return 0; 201 } 202 203 const struct file_operations udf_file_operations = { 204 .read = do_sync_read, 205 .aio_read = generic_file_aio_read, 206 .ioctl = udf_ioctl, 207 .open = generic_file_open, 208 .mmap = generic_file_mmap, 209 .write = do_sync_write, 210 .aio_write = udf_file_aio_write, 211 .release = udf_release_file, 212 .fsync = udf_fsync_file, 213 .splice_read = generic_file_splice_read, 214 .llseek = generic_file_llseek, 215 }; 216 217 const struct inode_operations udf_file_inode_operations = { 218 .truncate = udf_truncate, 219 }; 220