1/* 2 * file.c 3 * 4 * Copyright (C) 1995, 1996, 1997 by Paal-Kr. Engstad and Volker Lendecke 5 * Copyright (C) 1997 by Volker Lendecke 6 * 7 * Please add a note about your changes to smbfs in the ChangeLog file. 8 */ 9 10#include <linux/time.h> 11#include <linux/kernel.h> 12#include <linux/errno.h> 13#include <linux/fcntl.h> 14#include <linux/stat.h> 15#include <linux/mm.h> 16#include <linux/slab.h> 17#include <linux/pagemap.h> 18#include <linux/smp_lock.h> 19#include <linux/net.h> 20#include <linux/aio.h> 21 22#include <asm/uaccess.h> 23#include <asm/system.h> 24 25#include <linux/smbno.h> 26#include <linux/smb_fs.h> 27 28#include "smb_debug.h" 29#include "proto.h" 30 31static int 32smb_fsync(struct file *file, struct dentry * dentry, int datasync) 33{ 34 struct smb_sb_info *server = server_from_dentry(dentry); 35 int result; 36 37 VERBOSE("sync file %s/%s\n", DENTRY_PATH(dentry)); 38 39 /* 40 * The VFS will writepage() all dirty pages for us, but we 41 * should send a SMBflush to the server, letting it know that 42 * we want things synchronized with actual storage. 43 * 44 * Note: this function requires all pages to have been written already 45 * (should be ok with writepage_sync) 46 */ 47 result = smb_proc_flush(server, SMB_I(dentry->d_inode)->fileid); 48 return result; 49} 50 51/* 52 * Read a page synchronously. 53 */ 54static int 55smb_readpage_sync(struct dentry *dentry, struct page *page) 56{ 57 char *buffer = kmap(page); 58 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT; 59 struct smb_sb_info *server = server_from_dentry(dentry); 60 unsigned int rsize = smb_get_rsize(server); 61 int count = PAGE_SIZE; 62 int result; 63 64 VERBOSE("file %s/%s, count=%d@%Ld, rsize=%d\n", 65 DENTRY_PATH(dentry), count, offset, rsize); 66 67 result = smb_open(dentry, SMB_O_RDONLY); 68 if (result < 0) 69 goto io_error; 70 71 do { 72 if (count < rsize) 73 rsize = count; 74 75 result = server->ops->read(dentry->d_inode,offset,rsize,buffer); 76 if (result < 0) 77 goto io_error; 78 79 count -= result; 80 offset += result; 81 buffer += result; 82 dentry->d_inode->i_atime = 83 current_fs_time(dentry->d_inode->i_sb); 84 if (result < rsize) 85 break; 86 } while (count); 87 88 memset(buffer, 0, count); 89 flush_dcache_page(page); 90 SetPageUptodate(page); 91 result = 0; 92 93io_error: 94 kunmap(page); 95 unlock_page(page); 96 return result; 97} 98 99/* 100 * We are called with the page locked and we unlock it when done. 101 */ 102static int 103smb_readpage(struct file *file, struct page *page) 104{ 105 int error; 106 struct dentry *dentry = file->f_path.dentry; 107 108 page_cache_get(page); 109 error = smb_readpage_sync(dentry, page); 110 page_cache_release(page); 111 return error; 112} 113 114/* 115 * Write a page synchronously. 116 * Offset is the data offset within the page. 117 */ 118static int 119smb_writepage_sync(struct inode *inode, struct page *page, 120 unsigned long pageoffset, unsigned int count) 121{ 122 loff_t offset; 123 char *buffer = kmap(page) + pageoffset; 124 struct smb_sb_info *server = server_from_inode(inode); 125 unsigned int wsize = smb_get_wsize(server); 126 int ret = 0; 127 128 offset = ((loff_t)page->index << PAGE_CACHE_SHIFT) + pageoffset; 129 VERBOSE("file ino=%ld, fileid=%d, count=%d@%Ld, wsize=%d\n", 130 inode->i_ino, SMB_I(inode)->fileid, count, offset, wsize); 131 132 do { 133 int write_ret; 134 135 if (count < wsize) 136 wsize = count; 137 138 write_ret = server->ops->write(inode, offset, wsize, buffer); 139 if (write_ret < 0) { 140 PARANOIA("failed write, wsize=%d, write_ret=%d\n", 141 wsize, write_ret); 142 ret = write_ret; 143 break; 144 } 145 /* N.B. what if result < wsize?? */ 146#ifdef SMBFS_PARANOIA 147 if (write_ret < wsize) 148 PARANOIA("short write, wsize=%d, write_ret=%d\n", 149 wsize, write_ret); 150#endif 151 buffer += wsize; 152 offset += wsize; 153 count -= wsize; 154 /* 155 * Update the inode now rather than waiting for a refresh. 156 */ 157 inode->i_mtime = inode->i_atime = current_fs_time(inode->i_sb); 158 SMB_I(inode)->flags |= SMB_F_LOCALWRITE; 159 if (offset > inode->i_size) 160 inode->i_size = offset; 161 } while (count); 162 163 kunmap(page); 164 return ret; 165} 166 167/* 168 * Write a page to the server. This will be used for NFS swapping only 169 * (for now), and we currently do this synchronously only. 170 * 171 * We are called with the page locked and we unlock it when done. 172 */ 173static int 174smb_writepage(struct page *page, struct writeback_control *wbc) 175{ 176 struct address_space *mapping = page->mapping; 177 struct inode *inode; 178 unsigned long end_index; 179 unsigned offset = PAGE_CACHE_SIZE; 180 int err; 181 182 BUG_ON(!mapping); 183 inode = mapping->host; 184 BUG_ON(!inode); 185 186 end_index = inode->i_size >> PAGE_CACHE_SHIFT; 187 188 /* easy case */ 189 if (page->index < end_index) 190 goto do_it; 191 /* things got complicated... */ 192 offset = inode->i_size & (PAGE_CACHE_SIZE-1); 193 /* OK, are we completely out? */ 194 if (page->index >= end_index+1 || !offset) 195 return 0; /* truncated - don't care */ 196do_it: 197 page_cache_get(page); 198 err = smb_writepage_sync(inode, page, 0, offset); 199 SetPageUptodate(page); 200 unlock_page(page); 201 page_cache_release(page); 202 return err; 203} 204 205static int 206smb_updatepage(struct file *file, struct page *page, unsigned long offset, 207 unsigned int count) 208{ 209 struct dentry *dentry = file->f_path.dentry; 210 211 DEBUG1("(%s/%s %d@%lld)\n", DENTRY_PATH(dentry), count, 212 ((unsigned long long)page->index << PAGE_CACHE_SHIFT) + offset); 213 214 return smb_writepage_sync(dentry->d_inode, page, offset, count); 215} 216 217static ssize_t 218smb_file_aio_read(struct kiocb *iocb, const struct iovec *iov, 219 unsigned long nr_segs, loff_t pos) 220{ 221 struct file * file = iocb->ki_filp; 222 struct dentry * dentry = file->f_path.dentry; 223 ssize_t status; 224 225 VERBOSE("file %s/%s, count=%lu@%lu\n", DENTRY_PATH(dentry), 226 (unsigned long) iocb->ki_left, (unsigned long) pos); 227 228 status = smb_revalidate_inode(dentry); 229 if (status) { 230 PARANOIA("%s/%s validation failed, error=%Zd\n", 231 DENTRY_PATH(dentry), status); 232 goto out; 233 } 234 235 VERBOSE("before read, size=%ld, flags=%x, atime=%ld\n", 236 (long)dentry->d_inode->i_size, 237 dentry->d_inode->i_flags, dentry->d_inode->i_atime); 238 239 status = generic_file_aio_read(iocb, iov, nr_segs, pos); 240out: 241 return status; 242} 243 244static int 245smb_file_mmap(struct file * file, struct vm_area_struct * vma) 246{ 247 struct dentry * dentry = file->f_path.dentry; 248 int status; 249 250 VERBOSE("file %s/%s, address %lu - %lu\n", 251 DENTRY_PATH(dentry), vma->vm_start, vma->vm_end); 252 253 status = smb_revalidate_inode(dentry); 254 if (status) { 255 PARANOIA("%s/%s validation failed, error=%d\n", 256 DENTRY_PATH(dentry), status); 257 goto out; 258 } 259 status = generic_file_mmap(file, vma); 260out: 261 return status; 262} 263 264static ssize_t 265smb_file_sendfile(struct file *file, loff_t *ppos, 266 size_t count, read_actor_t actor, void *target) 267{ 268 struct dentry *dentry = file->f_path.dentry; 269 ssize_t status; 270 271 VERBOSE("file %s/%s, pos=%Ld, count=%d\n", 272 DENTRY_PATH(dentry), *ppos, count); 273 274 status = smb_revalidate_inode(dentry); 275 if (status) { 276 PARANOIA("%s/%s validation failed, error=%Zd\n", 277 DENTRY_PATH(dentry), status); 278 goto out; 279 } 280 status = generic_file_sendfile(file, ppos, count, actor, target); 281out: 282 return status; 283} 284 285/* 286 * This does the "real" work of the write. The generic routine has 287 * allocated the page, locked it, done all the page alignment stuff 288 * calculations etc. Now we should just copy the data from user 289 * space and write it back to the real medium.. 290 * 291 * If the writer ends up delaying the write, the writer needs to 292 * increment the page use counts until he is done with the page. 293 */ 294static int smb_prepare_write(struct file *file, struct page *page, 295 unsigned offset, unsigned to) 296{ 297 return 0; 298} 299 300static int smb_commit_write(struct file *file, struct page *page, 301 unsigned offset, unsigned to) 302{ 303 int status; 304 305 status = -EFAULT; 306 lock_kernel(); 307 status = smb_updatepage(file, page, offset, to-offset); 308 unlock_kernel(); 309 return status; 310} 311 312const struct address_space_operations smb_file_aops = { 313 .readpage = smb_readpage, 314 .writepage = smb_writepage, 315 .prepare_write = smb_prepare_write, 316 .commit_write = smb_commit_write 317}; 318 319/* 320 * Write to a file (through the page cache). 321 */ 322static ssize_t 323smb_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 324 unsigned long nr_segs, loff_t pos) 325{ 326 struct file * file = iocb->ki_filp; 327 struct dentry * dentry = file->f_path.dentry; 328 ssize_t result; 329 330 VERBOSE("file %s/%s, count=%lu@%lu\n", 331 DENTRY_PATH(dentry), 332 (unsigned long) iocb->ki_left, (unsigned long) pos); 333 334 result = smb_revalidate_inode(dentry); 335 if (result) { 336 PARANOIA("%s/%s validation failed, error=%Zd\n", 337 DENTRY_PATH(dentry), result); 338 goto out; 339 } 340 341 result = smb_open(dentry, SMB_O_WRONLY); 342 if (result) 343 goto out; 344 345 if (iocb->ki_left > 0) { 346 result = generic_file_aio_write(iocb, iov, nr_segs, pos); 347 VERBOSE("pos=%ld, size=%ld, mtime=%ld, atime=%ld\n", 348 (long) file->f_pos, (long) dentry->d_inode->i_size, 349 dentry->d_inode->i_mtime, dentry->d_inode->i_atime); 350 } 351out: 352 return result; 353} 354 355static int 356smb_file_open(struct inode *inode, struct file * file) 357{ 358 int result; 359 struct dentry *dentry = file->f_path.dentry; 360 int smb_mode = (file->f_mode & O_ACCMODE) - 1; 361 362 lock_kernel(); 363 result = smb_open(dentry, smb_mode); 364 if (result) 365 goto out; 366 SMB_I(inode)->openers++; 367out: 368 unlock_kernel(); 369 return result; 370} 371 372static int 373smb_file_release(struct inode *inode, struct file * file) 374{ 375 lock_kernel(); 376 if (!--SMB_I(inode)->openers) { 377 /* We must flush any dirty pages now as we won't be able to 378 write anything after close. mmap can trigger this. 379 "openers" should perhaps include mmap'ers ... */ 380 filemap_write_and_wait(inode->i_mapping); 381 smb_close(inode); 382 } 383 unlock_kernel(); 384 return 0; 385} 386 387/* 388 * Check whether the required access is compatible with 389 * an inode's permission. SMB doesn't recognize superuser 390 * privileges, so we need our own check for this. 391 */ 392static int 393smb_file_permission(struct inode *inode, int mask, struct nameidata *nd) 394{ 395 int mode = inode->i_mode; 396 int error = 0; 397 398 VERBOSE("mode=%x, mask=%x\n", mode, mask); 399 400 /* Look at user permissions */ 401 mode >>= 6; 402 if ((mode & 7 & mask) != mask) 403 error = -EACCES; 404 return error; 405} 406 407const struct file_operations smb_file_operations = 408{ 409 .llseek = remote_llseek, 410 .read = do_sync_read, 411 .aio_read = smb_file_aio_read, 412 .write = do_sync_write, 413 .aio_write = smb_file_aio_write, 414 .ioctl = smb_ioctl, 415 .mmap = smb_file_mmap, 416 .open = smb_file_open, 417 .release = smb_file_release, 418 .fsync = smb_fsync, 419 .sendfile = smb_file_sendfile, 420}; 421 422const struct inode_operations smb_file_inode_operations = 423{ 424 .permission = smb_file_permission, 425 .getattr = smb_getattr, 426 .setattr = smb_notify_change, 427}; 428