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/pagemap.h> 17#include <linux/smp_lock.h> 18#include <linux/net.h> 19#include <linux/aio.h> 20 21#include <asm/uaccess.h> 22#include <asm/system.h> 23 24#include <linux/smbno.h> 25#include <linux/smb_fs.h> 26 27#include "smb_debug.h" 28#include "proto.h" 29 30static int 31smb_fsync(struct file *file, int datasync) 32{ 33 struct dentry *dentry = file->f_path.dentry; 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.tv_sec); 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_splice_read(struct file *file, loff_t *ppos, 266 struct pipe_inode_info *pipe, size_t count, 267 unsigned int flags) 268{ 269 struct dentry *dentry = file->f_path.dentry; 270 ssize_t status; 271 272 VERBOSE("file %s/%s, pos=%Ld, count=%lu\n", 273 DENTRY_PATH(dentry), *ppos, count); 274 275 status = smb_revalidate_inode(dentry); 276 if (status) { 277 PARANOIA("%s/%s validation failed, error=%Zd\n", 278 DENTRY_PATH(dentry), status); 279 goto out; 280 } 281 status = generic_file_splice_read(file, ppos, pipe, count, flags); 282out: 283 return status; 284} 285 286/* 287 * This does the "real" work of the write. The generic routine has 288 * allocated the page, locked it, done all the page alignment stuff 289 * calculations etc. Now we should just copy the data from user 290 * space and write it back to the real medium.. 291 * 292 * If the writer ends up delaying the write, the writer needs to 293 * increment the page use counts until he is done with the page. 294 */ 295static int smb_write_begin(struct file *file, struct address_space *mapping, 296 loff_t pos, unsigned len, unsigned flags, 297 struct page **pagep, void **fsdata) 298{ 299 pgoff_t index = pos >> PAGE_CACHE_SHIFT; 300 *pagep = grab_cache_page_write_begin(mapping, index, flags); 301 if (!*pagep) 302 return -ENOMEM; 303 return 0; 304} 305 306static int smb_write_end(struct file *file, struct address_space *mapping, 307 loff_t pos, unsigned len, unsigned copied, 308 struct page *page, void *fsdata) 309{ 310 int status; 311 unsigned offset = pos & (PAGE_CACHE_SIZE - 1); 312 313 lock_kernel(); 314 status = smb_updatepage(file, page, offset, copied); 315 unlock_kernel(); 316 317 if (!status) { 318 if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE) 319 SetPageUptodate(page); 320 status = copied; 321 } 322 323 unlock_page(page); 324 page_cache_release(page); 325 326 return status; 327} 328 329const struct address_space_operations smb_file_aops = { 330 .readpage = smb_readpage, 331 .writepage = smb_writepage, 332 .write_begin = smb_write_begin, 333 .write_end = smb_write_end, 334}; 335 336/* 337 * Write to a file (through the page cache). 338 */ 339static ssize_t 340smb_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 341 unsigned long nr_segs, loff_t pos) 342{ 343 struct file * file = iocb->ki_filp; 344 struct dentry * dentry = file->f_path.dentry; 345 ssize_t result; 346 347 VERBOSE("file %s/%s, count=%lu@%lu\n", 348 DENTRY_PATH(dentry), 349 (unsigned long) iocb->ki_left, (unsigned long) pos); 350 351 result = smb_revalidate_inode(dentry); 352 if (result) { 353 PARANOIA("%s/%s validation failed, error=%Zd\n", 354 DENTRY_PATH(dentry), result); 355 goto out; 356 } 357 358 result = smb_open(dentry, SMB_O_WRONLY); 359 if (result) 360 goto out; 361 362 if (iocb->ki_left > 0) { 363 result = generic_file_aio_write(iocb, iov, nr_segs, pos); 364 VERBOSE("pos=%ld, size=%ld, mtime=%ld, atime=%ld\n", 365 (long) file->f_pos, (long) dentry->d_inode->i_size, 366 dentry->d_inode->i_mtime.tv_sec, 367 dentry->d_inode->i_atime.tv_sec); 368 } 369out: 370 return result; 371} 372 373static int 374smb_file_open(struct inode *inode, struct file * file) 375{ 376 int result; 377 struct dentry *dentry = file->f_path.dentry; 378 int smb_mode = (file->f_mode & O_ACCMODE) - 1; 379 380 lock_kernel(); 381 result = smb_open(dentry, smb_mode); 382 if (result) 383 goto out; 384 SMB_I(inode)->openers++; 385out: 386 unlock_kernel(); 387 return result; 388} 389 390static int 391smb_file_release(struct inode *inode, struct file * file) 392{ 393 lock_kernel(); 394 if (!--SMB_I(inode)->openers) { 395 /* We must flush any dirty pages now as we won't be able to 396 write anything after close. mmap can trigger this. 397 "openers" should perhaps include mmap'ers ... */ 398 filemap_write_and_wait(inode->i_mapping); 399 smb_close(inode); 400 } 401 unlock_kernel(); 402 return 0; 403} 404 405/* 406 * Check whether the required access is compatible with 407 * an inode's permission. SMB doesn't recognize superuser 408 * privileges, so we need our own check for this. 409 */ 410static int 411smb_file_permission(struct inode *inode, int mask) 412{ 413 int mode = inode->i_mode; 414 int error = 0; 415 416 VERBOSE("mode=%x, mask=%x\n", mode, mask); 417 418 /* Look at user permissions */ 419 mode >>= 6; 420 if (mask & ~mode & (MAY_READ | MAY_WRITE | MAY_EXEC)) 421 error = -EACCES; 422 return error; 423} 424 425static loff_t smb_remote_llseek(struct file *file, loff_t offset, int origin) 426{ 427 loff_t ret; 428 lock_kernel(); 429 ret = generic_file_llseek_unlocked(file, offset, origin); 430 unlock_kernel(); 431 return ret; 432} 433 434const struct file_operations smb_file_operations = 435{ 436 .llseek = smb_remote_llseek, 437 .read = do_sync_read, 438 .aio_read = smb_file_aio_read, 439 .write = do_sync_write, 440 .aio_write = smb_file_aio_write, 441 .unlocked_ioctl = smb_ioctl, 442 .mmap = smb_file_mmap, 443 .open = smb_file_open, 444 .release = smb_file_release, 445 .fsync = smb_fsync, 446 .splice_read = smb_file_splice_read, 447}; 448 449const struct inode_operations smb_file_inode_operations = 450{ 451 .permission = smb_file_permission, 452 .getattr = smb_getattr, 453 .setattr = smb_notify_change, 454}; 455