Commit 797b4cffdf79b9ed66759b8d2d5252eba965fb18
Committed by
Linus Torvalds
1 parent
f870618428
reiserfs: use generic write
Make reiserfs to write via generic routines. Original reiserfs write optimized for big writes is deadlock rone Signed-off-by: Vladimir Saveliev <vs@namesys.com> Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing 1 changed file with 1 additions and 1239 deletions Side-by-side Diff
fs/reiserfs/file.c
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... | ... | @@ -153,608 +153,6 @@ |
153 | 153 | return (n_err < 0) ? -EIO : 0; |
154 | 154 | } |
155 | 155 | |
156 | -/* I really do not want to play with memory shortage right now, so | |
157 | - to simplify the code, we are not going to write more than this much pages at | |
158 | - a time. This still should considerably improve performance compared to 4k | |
159 | - at a time case. This is 32 pages of 4k size. */ | |
160 | -#define REISERFS_WRITE_PAGES_AT_A_TIME (128 * 1024) / PAGE_CACHE_SIZE | |
161 | - | |
162 | -/* Allocates blocks for a file to fulfil write request. | |
163 | - Maps all unmapped but prepared pages from the list. | |
164 | - Updates metadata with newly allocated blocknumbers as needed */ | |
165 | -static int reiserfs_allocate_blocks_for_region(struct reiserfs_transaction_handle *th, struct inode *inode, /* Inode we work with */ | |
166 | - loff_t pos, /* Writing position */ | |
167 | - int num_pages, /* number of pages write going | |
168 | - to touch */ | |
169 | - int write_bytes, /* amount of bytes to write */ | |
170 | - struct page **prepared_pages, /* array of | |
171 | - prepared pages | |
172 | - */ | |
173 | - int blocks_to_allocate /* Amount of blocks we | |
174 | - need to allocate to | |
175 | - fit the data into file | |
176 | - */ | |
177 | - ) | |
178 | -{ | |
179 | - struct cpu_key key; // cpu key of item that we are going to deal with | |
180 | - struct item_head *ih; // pointer to item head that we are going to deal with | |
181 | - struct buffer_head *bh; // Buffer head that contains items that we are going to deal with | |
182 | - __le32 *item; // pointer to item we are going to deal with | |
183 | - INITIALIZE_PATH(path); // path to item, that we are going to deal with. | |
184 | - b_blocknr_t *allocated_blocks; // Pointer to a place where allocated blocknumbers would be stored. | |
185 | - reiserfs_blocknr_hint_t hint; // hint structure for block allocator. | |
186 | - size_t res; // return value of various functions that we call. | |
187 | - int curr_block; // current block used to keep track of unmapped blocks. | |
188 | - int i; // loop counter | |
189 | - int itempos; // position in item | |
190 | - unsigned int from = (pos & (PAGE_CACHE_SIZE - 1)); // writing position in | |
191 | - // first page | |
192 | - unsigned int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1; /* last modified byte offset in last page */ | |
193 | - __u64 hole_size; // amount of blocks for a file hole, if it needed to be created. | |
194 | - int modifying_this_item = 0; // Flag for items traversal code to keep track | |
195 | - // of the fact that we already prepared | |
196 | - // current block for journal | |
197 | - int will_prealloc = 0; | |
198 | - RFALSE(!blocks_to_allocate, | |
199 | - "green-9004: tried to allocate zero blocks?"); | |
200 | - | |
201 | - /* only preallocate if this is a small write */ | |
202 | - if (REISERFS_I(inode)->i_prealloc_count || | |
203 | - (!(write_bytes & (inode->i_sb->s_blocksize - 1)) && | |
204 | - blocks_to_allocate < | |
205 | - REISERFS_SB(inode->i_sb)->s_alloc_options.preallocsize)) | |
206 | - will_prealloc = | |
207 | - REISERFS_SB(inode->i_sb)->s_alloc_options.preallocsize; | |
208 | - | |
209 | - allocated_blocks = kmalloc((blocks_to_allocate + will_prealloc) * | |
210 | - sizeof(b_blocknr_t), GFP_NOFS); | |
211 | - if (!allocated_blocks) | |
212 | - return -ENOMEM; | |
213 | - | |
214 | - /* First we compose a key to point at the writing position, we want to do | |
215 | - that outside of any locking region. */ | |
216 | - make_cpu_key(&key, inode, pos + 1, TYPE_ANY, 3 /*key length */ ); | |
217 | - | |
218 | - /* If we came here, it means we absolutely need to open a transaction, | |
219 | - since we need to allocate some blocks */ | |
220 | - reiserfs_write_lock(inode->i_sb); // Journaling stuff and we need that. | |
221 | - res = journal_begin(th, inode->i_sb, JOURNAL_PER_BALANCE_CNT * 3 + 1 + 2 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb)); // Wish I know if this number enough | |
222 | - if (res) | |
223 | - goto error_exit; | |
224 | - reiserfs_update_inode_transaction(inode); | |
225 | - | |
226 | - /* Look for the in-tree position of our write, need path for block allocator */ | |
227 | - res = search_for_position_by_key(inode->i_sb, &key, &path); | |
228 | - if (res == IO_ERROR) { | |
229 | - res = -EIO; | |
230 | - goto error_exit; | |
231 | - } | |
232 | - | |
233 | - /* Allocate blocks */ | |
234 | - /* First fill in "hint" structure for block allocator */ | |
235 | - hint.th = th; // transaction handle. | |
236 | - hint.path = &path; // Path, so that block allocator can determine packing locality or whatever it needs to determine. | |
237 | - hint.inode = inode; // Inode is needed by block allocator too. | |
238 | - hint.search_start = 0; // We have no hint on where to search free blocks for block allocator. | |
239 | - hint.key = key.on_disk_key; // on disk key of file. | |
240 | - hint.block = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); // Number of disk blocks this file occupies already. | |
241 | - hint.formatted_node = 0; // We are allocating blocks for unformatted node. | |
242 | - hint.preallocate = will_prealloc; | |
243 | - | |
244 | - /* Call block allocator to allocate blocks */ | |
245 | - res = | |
246 | - reiserfs_allocate_blocknrs(&hint, allocated_blocks, | |
247 | - blocks_to_allocate, blocks_to_allocate); | |
248 | - if (res != CARRY_ON) { | |
249 | - if (res == NO_DISK_SPACE) { | |
250 | - /* We flush the transaction in case of no space. This way some | |
251 | - blocks might become free */ | |
252 | - SB_JOURNAL(inode->i_sb)->j_must_wait = 1; | |
253 | - res = restart_transaction(th, inode, &path); | |
254 | - if (res) | |
255 | - goto error_exit; | |
256 | - | |
257 | - /* We might have scheduled, so search again */ | |
258 | - res = | |
259 | - search_for_position_by_key(inode->i_sb, &key, | |
260 | - &path); | |
261 | - if (res == IO_ERROR) { | |
262 | - res = -EIO; | |
263 | - goto error_exit; | |
264 | - } | |
265 | - | |
266 | - /* update changed info for hint structure. */ | |
267 | - res = | |
268 | - reiserfs_allocate_blocknrs(&hint, allocated_blocks, | |
269 | - blocks_to_allocate, | |
270 | - blocks_to_allocate); | |
271 | - if (res != CARRY_ON) { | |
272 | - res = res == QUOTA_EXCEEDED ? -EDQUOT : -ENOSPC; | |
273 | - pathrelse(&path); | |
274 | - goto error_exit; | |
275 | - } | |
276 | - } else { | |
277 | - res = res == QUOTA_EXCEEDED ? -EDQUOT : -ENOSPC; | |
278 | - pathrelse(&path); | |
279 | - goto error_exit; | |
280 | - } | |
281 | - } | |
282 | -#ifdef __BIG_ENDIAN | |
283 | - // Too bad, I have not found any way to convert a given region from | |
284 | - // cpu format to little endian format | |
285 | - { | |
286 | - int i; | |
287 | - for (i = 0; i < blocks_to_allocate; i++) | |
288 | - allocated_blocks[i] = cpu_to_le32(allocated_blocks[i]); | |
289 | - } | |
290 | -#endif | |
291 | - | |
292 | - /* Blocks allocating well might have scheduled and tree might have changed, | |
293 | - let's search the tree again */ | |
294 | - /* find where in the tree our write should go */ | |
295 | - res = search_for_position_by_key(inode->i_sb, &key, &path); | |
296 | - if (res == IO_ERROR) { | |
297 | - res = -EIO; | |
298 | - goto error_exit_free_blocks; | |
299 | - } | |
300 | - | |
301 | - bh = get_last_bh(&path); // Get a bufferhead for last element in path. | |
302 | - ih = get_ih(&path); // Get a pointer to last item head in path. | |
303 | - item = get_item(&path); // Get a pointer to last item in path | |
304 | - | |
305 | - /* Let's see what we have found */ | |
306 | - if (res != POSITION_FOUND) { /* position not found, this means that we | |
307 | - might need to append file with holes | |
308 | - first */ | |
309 | - // Since we are writing past the file's end, we need to find out if | |
310 | - // there is a hole that needs to be inserted before our writing | |
311 | - // position, and how many blocks it is going to cover (we need to | |
312 | - // populate pointers to file blocks representing the hole with zeros) | |
313 | - | |
314 | - { | |
315 | - int item_offset = 1; | |
316 | - /* | |
317 | - * if ih is stat data, its offset is 0 and we don't want to | |
318 | - * add 1 to pos in the hole_size calculation | |
319 | - */ | |
320 | - if (is_statdata_le_ih(ih)) | |
321 | - item_offset = 0; | |
322 | - hole_size = (pos + item_offset - | |
323 | - (le_key_k_offset | |
324 | - (get_inode_item_key_version(inode), | |
325 | - &(ih->ih_key)) + op_bytes_number(ih, | |
326 | - inode-> | |
327 | - i_sb-> | |
328 | - s_blocksize))) | |
329 | - >> inode->i_sb->s_blocksize_bits; | |
330 | - } | |
331 | - | |
332 | - if (hole_size > 0) { | |
333 | - int to_paste = min_t(__u64, hole_size, MAX_ITEM_LEN(inode->i_sb->s_blocksize) / UNFM_P_SIZE); // How much data to insert first time. | |
334 | - /* area filled with zeroes, to supply as list of zero blocknumbers | |
335 | - We allocate it outside of loop just in case loop would spin for | |
336 | - several iterations. */ | |
337 | - char *zeros = kzalloc(to_paste * UNFM_P_SIZE, GFP_ATOMIC); // We cannot insert more than MAX_ITEM_LEN bytes anyway. | |
338 | - if (!zeros) { | |
339 | - res = -ENOMEM; | |
340 | - goto error_exit_free_blocks; | |
341 | - } | |
342 | - do { | |
343 | - to_paste = | |
344 | - min_t(__u64, hole_size, | |
345 | - MAX_ITEM_LEN(inode->i_sb-> | |
346 | - s_blocksize) / | |
347 | - UNFM_P_SIZE); | |
348 | - if (is_indirect_le_ih(ih)) { | |
349 | - /* Ok, there is existing indirect item already. Need to append it */ | |
350 | - /* Calculate position past inserted item */ | |
351 | - make_cpu_key(&key, inode, | |
352 | - le_key_k_offset | |
353 | - (get_inode_item_key_version | |
354 | - (inode), | |
355 | - &(ih->ih_key)) + | |
356 | - op_bytes_number(ih, | |
357 | - inode-> | |
358 | - i_sb-> | |
359 | - s_blocksize), | |
360 | - TYPE_INDIRECT, 3); | |
361 | - res = | |
362 | - reiserfs_paste_into_item(th, &path, | |
363 | - &key, | |
364 | - inode, | |
365 | - (char *) | |
366 | - zeros, | |
367 | - UNFM_P_SIZE | |
368 | - * | |
369 | - to_paste); | |
370 | - if (res) { | |
371 | - kfree(zeros); | |
372 | - goto error_exit_free_blocks; | |
373 | - } | |
374 | - } else if (is_statdata_le_ih(ih)) { | |
375 | - /* No existing item, create it */ | |
376 | - /* item head for new item */ | |
377 | - struct item_head ins_ih; | |
378 | - | |
379 | - /* create a key for our new item */ | |
380 | - make_cpu_key(&key, inode, 1, | |
381 | - TYPE_INDIRECT, 3); | |
382 | - | |
383 | - /* Create new item head for our new item */ | |
384 | - make_le_item_head(&ins_ih, &key, | |
385 | - key.version, 1, | |
386 | - TYPE_INDIRECT, | |
387 | - to_paste * | |
388 | - UNFM_P_SIZE, | |
389 | - 0 /* free space */ ); | |
390 | - | |
391 | - /* Find where such item should live in the tree */ | |
392 | - res = | |
393 | - search_item(inode->i_sb, &key, | |
394 | - &path); | |
395 | - if (res != ITEM_NOT_FOUND) { | |
396 | - /* item should not exist, otherwise we have error */ | |
397 | - if (res != -ENOSPC) { | |
398 | - reiserfs_warning(inode-> | |
399 | - i_sb, | |
400 | - "green-9008: search_by_key (%K) returned %d", | |
401 | - &key, | |
402 | - res); | |
403 | - } | |
404 | - res = -EIO; | |
405 | - kfree(zeros); | |
406 | - goto error_exit_free_blocks; | |
407 | - } | |
408 | - res = | |
409 | - reiserfs_insert_item(th, &path, | |
410 | - &key, &ins_ih, | |
411 | - inode, | |
412 | - (char *)zeros); | |
413 | - } else { | |
414 | - reiserfs_panic(inode->i_sb, | |
415 | - "green-9011: Unexpected key type %K\n", | |
416 | - &key); | |
417 | - } | |
418 | - if (res) { | |
419 | - kfree(zeros); | |
420 | - goto error_exit_free_blocks; | |
421 | - } | |
422 | - /* Now we want to check if transaction is too full, and if it is | |
423 | - we restart it. This will also free the path. */ | |
424 | - if (journal_transaction_should_end | |
425 | - (th, th->t_blocks_allocated)) { | |
426 | - inode->i_size = cpu_key_k_offset(&key) + | |
427 | - (to_paste << inode->i_blkbits); | |
428 | - res = | |
429 | - restart_transaction(th, inode, | |
430 | - &path); | |
431 | - if (res) { | |
432 | - pathrelse(&path); | |
433 | - kfree(zeros); | |
434 | - goto error_exit; | |
435 | - } | |
436 | - } | |
437 | - | |
438 | - /* Well, need to recalculate path and stuff */ | |
439 | - set_cpu_key_k_offset(&key, | |
440 | - cpu_key_k_offset(&key) + | |
441 | - (to_paste << inode-> | |
442 | - i_blkbits)); | |
443 | - res = | |
444 | - search_for_position_by_key(inode->i_sb, | |
445 | - &key, &path); | |
446 | - if (res == IO_ERROR) { | |
447 | - res = -EIO; | |
448 | - kfree(zeros); | |
449 | - goto error_exit_free_blocks; | |
450 | - } | |
451 | - bh = get_last_bh(&path); | |
452 | - ih = get_ih(&path); | |
453 | - item = get_item(&path); | |
454 | - hole_size -= to_paste; | |
455 | - } while (hole_size); | |
456 | - kfree(zeros); | |
457 | - } | |
458 | - } | |
459 | - // Go through existing indirect items first | |
460 | - // replace all zeroes with blocknumbers from list | |
461 | - // Note that if no corresponding item was found, by previous search, | |
462 | - // it means there are no existing in-tree representation for file area | |
463 | - // we are going to overwrite, so there is nothing to scan through for holes. | |
464 | - for (curr_block = 0, itempos = path.pos_in_item; | |
465 | - curr_block < blocks_to_allocate && res == POSITION_FOUND;) { | |
466 | - retry: | |
467 | - | |
468 | - if (itempos >= ih_item_len(ih) / UNFM_P_SIZE) { | |
469 | - /* We run out of data in this indirect item, let's look for another | |
470 | - one. */ | |
471 | - /* First if we are already modifying current item, log it */ | |
472 | - if (modifying_this_item) { | |
473 | - journal_mark_dirty(th, inode->i_sb, bh); | |
474 | - modifying_this_item = 0; | |
475 | - } | |
476 | - /* Then set the key to look for a new indirect item (offset of old | |
477 | - item is added to old item length */ | |
478 | - set_cpu_key_k_offset(&key, | |
479 | - le_key_k_offset | |
480 | - (get_inode_item_key_version(inode), | |
481 | - &(ih->ih_key)) + | |
482 | - op_bytes_number(ih, | |
483 | - inode->i_sb-> | |
484 | - s_blocksize)); | |
485 | - /* Search ofor position of new key in the tree. */ | |
486 | - res = | |
487 | - search_for_position_by_key(inode->i_sb, &key, | |
488 | - &path); | |
489 | - if (res == IO_ERROR) { | |
490 | - res = -EIO; | |
491 | - goto error_exit_free_blocks; | |
492 | - } | |
493 | - bh = get_last_bh(&path); | |
494 | - ih = get_ih(&path); | |
495 | - item = get_item(&path); | |
496 | - itempos = path.pos_in_item; | |
497 | - continue; // loop to check all kinds of conditions and so on. | |
498 | - } | |
499 | - /* Ok, we have correct position in item now, so let's see if it is | |
500 | - representing file hole (blocknumber is zero) and fill it if needed */ | |
501 | - if (!item[itempos]) { | |
502 | - /* Ok, a hole. Now we need to check if we already prepared this | |
503 | - block to be journaled */ | |
504 | - while (!modifying_this_item) { // loop until succeed | |
505 | - /* Well, this item is not journaled yet, so we must prepare | |
506 | - it for journal first, before we can change it */ | |
507 | - struct item_head tmp_ih; // We copy item head of found item, | |
508 | - // here to detect if fs changed under | |
509 | - // us while we were preparing for | |
510 | - // journal. | |
511 | - int fs_gen; // We store fs generation here to find if someone | |
512 | - // changes fs under our feet | |
513 | - | |
514 | - copy_item_head(&tmp_ih, ih); // Remember itemhead | |
515 | - fs_gen = get_generation(inode->i_sb); // remember fs generation | |
516 | - reiserfs_prepare_for_journal(inode->i_sb, bh, 1); // Prepare a buffer within which indirect item is stored for changing. | |
517 | - if (fs_changed(fs_gen, inode->i_sb) | |
518 | - && item_moved(&tmp_ih, &path)) { | |
519 | - // Sigh, fs was changed under us, we need to look for new | |
520 | - // location of item we are working with | |
521 | - | |
522 | - /* unmark prepaerd area as journaled and search for it's | |
523 | - new position */ | |
524 | - reiserfs_restore_prepared_buffer(inode-> | |
525 | - i_sb, | |
526 | - bh); | |
527 | - res = | |
528 | - search_for_position_by_key(inode-> | |
529 | - i_sb, | |
530 | - &key, | |
531 | - &path); | |
532 | - if (res == IO_ERROR) { | |
533 | - res = -EIO; | |
534 | - goto error_exit_free_blocks; | |
535 | - } | |
536 | - bh = get_last_bh(&path); | |
537 | - ih = get_ih(&path); | |
538 | - item = get_item(&path); | |
539 | - itempos = path.pos_in_item; | |
540 | - goto retry; | |
541 | - } | |
542 | - modifying_this_item = 1; | |
543 | - } | |
544 | - item[itempos] = allocated_blocks[curr_block]; // Assign new block | |
545 | - curr_block++; | |
546 | - } | |
547 | - itempos++; | |
548 | - } | |
549 | - | |
550 | - if (modifying_this_item) { // We need to log last-accessed block, if it | |
551 | - // was modified, but not logged yet. | |
552 | - journal_mark_dirty(th, inode->i_sb, bh); | |
553 | - } | |
554 | - | |
555 | - if (curr_block < blocks_to_allocate) { | |
556 | - // Oh, well need to append to indirect item, or to create indirect item | |
557 | - // if there weren't any | |
558 | - if (is_indirect_le_ih(ih)) { | |
559 | - // Existing indirect item - append. First calculate key for append | |
560 | - // position. We do not need to recalculate path as it should | |
561 | - // already point to correct place. | |
562 | - make_cpu_key(&key, inode, | |
563 | - le_key_k_offset(get_inode_item_key_version | |
564 | - (inode), | |
565 | - &(ih->ih_key)) + | |
566 | - op_bytes_number(ih, | |
567 | - inode->i_sb->s_blocksize), | |
568 | - TYPE_INDIRECT, 3); | |
569 | - res = | |
570 | - reiserfs_paste_into_item(th, &path, &key, inode, | |
571 | - (char *)(allocated_blocks + | |
572 | - curr_block), | |
573 | - UNFM_P_SIZE * | |
574 | - (blocks_to_allocate - | |
575 | - curr_block)); | |
576 | - if (res) { | |
577 | - goto error_exit_free_blocks; | |
578 | - } | |
579 | - } else if (is_statdata_le_ih(ih)) { | |
580 | - // Last found item was statdata. That means we need to create indirect item. | |
581 | - struct item_head ins_ih; /* itemhead for new item */ | |
582 | - | |
583 | - /* create a key for our new item */ | |
584 | - make_cpu_key(&key, inode, 1, TYPE_INDIRECT, 3); // Position one, | |
585 | - // because that's | |
586 | - // where first | |
587 | - // indirect item | |
588 | - // begins | |
589 | - /* Create new item head for our new item */ | |
590 | - make_le_item_head(&ins_ih, &key, key.version, 1, | |
591 | - TYPE_INDIRECT, | |
592 | - (blocks_to_allocate - | |
593 | - curr_block) * UNFM_P_SIZE, | |
594 | - 0 /* free space */ ); | |
595 | - /* Find where such item should live in the tree */ | |
596 | - res = search_item(inode->i_sb, &key, &path); | |
597 | - if (res != ITEM_NOT_FOUND) { | |
598 | - /* Well, if we have found such item already, or some error | |
599 | - occured, we need to warn user and return error */ | |
600 | - if (res != -ENOSPC) { | |
601 | - reiserfs_warning(inode->i_sb, | |
602 | - "green-9009: search_by_key (%K) " | |
603 | - "returned %d", &key, | |
604 | - res); | |
605 | - } | |
606 | - res = -EIO; | |
607 | - goto error_exit_free_blocks; | |
608 | - } | |
609 | - /* Insert item into the tree with the data as its body */ | |
610 | - res = | |
611 | - reiserfs_insert_item(th, &path, &key, &ins_ih, | |
612 | - inode, | |
613 | - (char *)(allocated_blocks + | |
614 | - curr_block)); | |
615 | - } else { | |
616 | - reiserfs_panic(inode->i_sb, | |
617 | - "green-9010: unexpected item type for key %K\n", | |
618 | - &key); | |
619 | - } | |
620 | - } | |
621 | - // the caller is responsible for closing the transaction | |
622 | - // unless we return an error, they are also responsible for logging | |
623 | - // the inode. | |
624 | - // | |
625 | - pathrelse(&path); | |
626 | - /* | |
627 | - * cleanup prellocation from previous writes | |
628 | - * if this is a partial block write | |
629 | - */ | |
630 | - if (write_bytes & (inode->i_sb->s_blocksize - 1)) | |
631 | - reiserfs_discard_prealloc(th, inode); | |
632 | - reiserfs_write_unlock(inode->i_sb); | |
633 | - | |
634 | - // go through all the pages/buffers and map the buffers to newly allocated | |
635 | - // blocks (so that system knows where to write these pages later). | |
636 | - curr_block = 0; | |
637 | - for (i = 0; i < num_pages; i++) { | |
638 | - struct page *page = prepared_pages[i]; //current page | |
639 | - struct buffer_head *head = page_buffers(page); // first buffer for a page | |
640 | - int block_start, block_end; // in-page offsets for buffers. | |
641 | - | |
642 | - if (!page_buffers(page)) | |
643 | - reiserfs_panic(inode->i_sb, | |
644 | - "green-9005: No buffers for prepared page???"); | |
645 | - | |
646 | - /* For each buffer in page */ | |
647 | - for (bh = head, block_start = 0; bh != head || !block_start; | |
648 | - block_start = block_end, bh = bh->b_this_page) { | |
649 | - if (!bh) | |
650 | - reiserfs_panic(inode->i_sb, | |
651 | - "green-9006: Allocated but absent buffer for a page?"); | |
652 | - block_end = block_start + inode->i_sb->s_blocksize; | |
653 | - if (i == 0 && block_end <= from) | |
654 | - /* if this buffer is before requested data to map, skip it */ | |
655 | - continue; | |
656 | - if (i == num_pages - 1 && block_start >= to) | |
657 | - /* If this buffer is after requested data to map, abort | |
658 | - processing of current page */ | |
659 | - break; | |
660 | - | |
661 | - if (!buffer_mapped(bh)) { // Ok, unmapped buffer, need to map it | |
662 | - map_bh(bh, inode->i_sb, | |
663 | - le32_to_cpu(allocated_blocks | |
664 | - [curr_block])); | |
665 | - curr_block++; | |
666 | - set_buffer_new(bh); | |
667 | - } | |
668 | - } | |
669 | - } | |
670 | - | |
671 | - RFALSE(curr_block > blocks_to_allocate, | |
672 | - "green-9007: Used too many blocks? weird"); | |
673 | - | |
674 | - kfree(allocated_blocks); | |
675 | - return 0; | |
676 | - | |
677 | -// Need to deal with transaction here. | |
678 | - error_exit_free_blocks: | |
679 | - pathrelse(&path); | |
680 | - // free blocks | |
681 | - for (i = 0; i < blocks_to_allocate; i++) | |
682 | - reiserfs_free_block(th, inode, le32_to_cpu(allocated_blocks[i]), | |
683 | - 1); | |
684 | - | |
685 | - error_exit: | |
686 | - if (th->t_trans_id) { | |
687 | - int err; | |
688 | - // update any changes we made to blk count | |
689 | - mark_inode_dirty(inode); | |
690 | - err = | |
691 | - journal_end(th, inode->i_sb, | |
692 | - JOURNAL_PER_BALANCE_CNT * 3 + 1 + | |
693 | - 2 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb)); | |
694 | - if (err) | |
695 | - res = err; | |
696 | - } | |
697 | - reiserfs_write_unlock(inode->i_sb); | |
698 | - kfree(allocated_blocks); | |
699 | - | |
700 | - return res; | |
701 | -} | |
702 | - | |
703 | -/* Unlock pages prepared by reiserfs_prepare_file_region_for_write */ | |
704 | -static void reiserfs_unprepare_pages(struct page **prepared_pages, /* list of locked pages */ | |
705 | - size_t num_pages /* amount of pages */ ) | |
706 | -{ | |
707 | - int i; // loop counter | |
708 | - | |
709 | - for (i = 0; i < num_pages; i++) { | |
710 | - struct page *page = prepared_pages[i]; | |
711 | - | |
712 | - try_to_free_buffers(page); | |
713 | - unlock_page(page); | |
714 | - page_cache_release(page); | |
715 | - } | |
716 | -} | |
717 | - | |
718 | -/* This function will copy data from userspace to specified pages within | |
719 | - supplied byte range */ | |
720 | -static int reiserfs_copy_from_user_to_file_region(loff_t pos, /* In-file position */ | |
721 | - int num_pages, /* Number of pages affected */ | |
722 | - int write_bytes, /* Amount of bytes to write */ | |
723 | - struct page **prepared_pages, /* pointer to | |
724 | - array to | |
725 | - prepared pages | |
726 | - */ | |
727 | - const char __user * buf /* Pointer to user-supplied | |
728 | - data */ | |
729 | - ) | |
730 | -{ | |
731 | - long page_fault = 0; // status of copy_from_user. | |
732 | - int i; // loop counter. | |
733 | - int offset; // offset in page | |
734 | - | |
735 | - for (i = 0, offset = (pos & (PAGE_CACHE_SIZE - 1)); i < num_pages; | |
736 | - i++, offset = 0) { | |
737 | - size_t count = min_t(size_t, PAGE_CACHE_SIZE - offset, write_bytes); // How much of bytes to write to this page | |
738 | - struct page *page = prepared_pages[i]; // Current page we process. | |
739 | - | |
740 | - fault_in_pages_readable(buf, count); | |
741 | - | |
742 | - /* Copy data from userspace to the current page */ | |
743 | - kmap(page); | |
744 | - page_fault = __copy_from_user(page_address(page) + offset, buf, count); // Copy the data. | |
745 | - /* Flush processor's dcache for this page */ | |
746 | - flush_dcache_page(page); | |
747 | - kunmap(page); | |
748 | - buf += count; | |
749 | - write_bytes -= count; | |
750 | - | |
751 | - if (page_fault) | |
752 | - break; // Was there a fault? abort. | |
753 | - } | |
754 | - | |
755 | - return page_fault ? -EFAULT : 0; | |
756 | -} | |
757 | - | |
758 | 156 | /* taken fs/buffer.c:__block_commit_write */ |
759 | 157 | int reiserfs_commit_page(struct inode *inode, struct page *page, |
760 | 158 | unsigned from, unsigned to) |
... | ... | @@ -824,432 +222,6 @@ |
824 | 222 | return ret; |
825 | 223 | } |
826 | 224 | |
827 | -/* Submit pages for write. This was separated from actual file copying | |
828 | - because we might want to allocate block numbers in-between. | |
829 | - This function assumes that caller will adjust file size to correct value. */ | |
830 | -static int reiserfs_submit_file_region_for_write(struct reiserfs_transaction_handle *th, struct inode *inode, loff_t pos, /* Writing position offset */ | |
831 | - size_t num_pages, /* Number of pages to write */ | |
832 | - size_t write_bytes, /* number of bytes to write */ | |
833 | - struct page **prepared_pages /* list of pages */ | |
834 | - ) | |
835 | -{ | |
836 | - int status; // return status of block_commit_write. | |
837 | - int retval = 0; // Return value we are going to return. | |
838 | - int i; // loop counter | |
839 | - int offset; // Writing offset in page. | |
840 | - int orig_write_bytes = write_bytes; | |
841 | - int sd_update = 0; | |
842 | - | |
843 | - for (i = 0, offset = (pos & (PAGE_CACHE_SIZE - 1)); i < num_pages; | |
844 | - i++, offset = 0) { | |
845 | - int count = min_t(int, PAGE_CACHE_SIZE - offset, write_bytes); // How much of bytes to write to this page | |
846 | - struct page *page = prepared_pages[i]; // Current page we process. | |
847 | - | |
848 | - status = | |
849 | - reiserfs_commit_page(inode, page, offset, offset + count); | |
850 | - if (status) | |
851 | - retval = status; // To not overcomplicate matters We are going to | |
852 | - // submit all the pages even if there was error. | |
853 | - // we only remember error status to report it on | |
854 | - // exit. | |
855 | - write_bytes -= count; | |
856 | - } | |
857 | - /* now that we've gotten all the ordered buffers marked dirty, | |
858 | - * we can safely update i_size and close any running transaction | |
859 | - */ | |
860 | - if (pos + orig_write_bytes > inode->i_size) { | |
861 | - inode->i_size = pos + orig_write_bytes; // Set new size | |
862 | - /* If the file have grown so much that tail packing is no | |
863 | - * longer possible, reset "need to pack" flag */ | |
864 | - if ((have_large_tails(inode->i_sb) && | |
865 | - inode->i_size > i_block_size(inode) * 4) || | |
866 | - (have_small_tails(inode->i_sb) && | |
867 | - inode->i_size > i_block_size(inode))) | |
868 | - REISERFS_I(inode)->i_flags &= ~i_pack_on_close_mask; | |
869 | - else if ((have_large_tails(inode->i_sb) && | |
870 | - inode->i_size < i_block_size(inode) * 4) || | |
871 | - (have_small_tails(inode->i_sb) && | |
872 | - inode->i_size < i_block_size(inode))) | |
873 | - REISERFS_I(inode)->i_flags |= i_pack_on_close_mask; | |
874 | - | |
875 | - if (th->t_trans_id) { | |
876 | - reiserfs_write_lock(inode->i_sb); | |
877 | - // this sets the proper flags for O_SYNC to trigger a commit | |
878 | - mark_inode_dirty(inode); | |
879 | - reiserfs_write_unlock(inode->i_sb); | |
880 | - } else { | |
881 | - reiserfs_write_lock(inode->i_sb); | |
882 | - reiserfs_update_inode_transaction(inode); | |
883 | - mark_inode_dirty(inode); | |
884 | - reiserfs_write_unlock(inode->i_sb); | |
885 | - } | |
886 | - | |
887 | - sd_update = 1; | |
888 | - } | |
889 | - if (th->t_trans_id) { | |
890 | - reiserfs_write_lock(inode->i_sb); | |
891 | - if (!sd_update) | |
892 | - mark_inode_dirty(inode); | |
893 | - status = journal_end(th, th->t_super, th->t_blocks_allocated); | |
894 | - if (status) | |
895 | - retval = status; | |
896 | - reiserfs_write_unlock(inode->i_sb); | |
897 | - } | |
898 | - th->t_trans_id = 0; | |
899 | - | |
900 | - /* | |
901 | - * we have to unlock the pages after updating i_size, otherwise | |
902 | - * we race with writepage | |
903 | - */ | |
904 | - for (i = 0; i < num_pages; i++) { | |
905 | - struct page *page = prepared_pages[i]; | |
906 | - unlock_page(page); | |
907 | - mark_page_accessed(page); | |
908 | - page_cache_release(page); | |
909 | - } | |
910 | - return retval; | |
911 | -} | |
912 | - | |
913 | -/* Look if passed writing region is going to touch file's tail | |
914 | - (if it is present). And if it is, convert the tail to unformatted node */ | |
915 | -static int reiserfs_check_for_tail_and_convert(struct inode *inode, /* inode to deal with */ | |
916 | - loff_t pos, /* Writing position */ | |
917 | - int write_bytes /* amount of bytes to write */ | |
918 | - ) | |
919 | -{ | |
920 | - INITIALIZE_PATH(path); // needed for search_for_position | |
921 | - struct cpu_key key; // Key that would represent last touched writing byte. | |
922 | - struct item_head *ih; // item header of found block; | |
923 | - int res; // Return value of various functions we call. | |
924 | - int cont_expand_offset; // We will put offset for generic_cont_expand here | |
925 | - // This can be int just because tails are created | |
926 | - // only for small files. | |
927 | - | |
928 | -/* this embodies a dependency on a particular tail policy */ | |
929 | - if (inode->i_size >= inode->i_sb->s_blocksize * 4) { | |
930 | - /* such a big files do not have tails, so we won't bother ourselves | |
931 | - to look for tails, simply return */ | |
932 | - return 0; | |
933 | - } | |
934 | - | |
935 | - reiserfs_write_lock(inode->i_sb); | |
936 | - /* find the item containing the last byte to be written, or if | |
937 | - * writing past the end of the file then the last item of the | |
938 | - * file (and then we check its type). */ | |
939 | - make_cpu_key(&key, inode, pos + write_bytes + 1, TYPE_ANY, | |
940 | - 3 /*key length */ ); | |
941 | - res = search_for_position_by_key(inode->i_sb, &key, &path); | |
942 | - if (res == IO_ERROR) { | |
943 | - reiserfs_write_unlock(inode->i_sb); | |
944 | - return -EIO; | |
945 | - } | |
946 | - ih = get_ih(&path); | |
947 | - res = 0; | |
948 | - if (is_direct_le_ih(ih)) { | |
949 | - /* Ok, closest item is file tail (tails are stored in "direct" | |
950 | - * items), so we need to unpack it. */ | |
951 | - /* To not overcomplicate matters, we just call generic_cont_expand | |
952 | - which will in turn call other stuff and finally will boil down to | |
953 | - reiserfs_get_block() that would do necessary conversion. */ | |
954 | - cont_expand_offset = | |
955 | - le_key_k_offset(get_inode_item_key_version(inode), | |
956 | - &(ih->ih_key)); | |
957 | - pathrelse(&path); | |
958 | - res = generic_cont_expand(inode, cont_expand_offset); | |
959 | - } else | |
960 | - pathrelse(&path); | |
961 | - | |
962 | - reiserfs_write_unlock(inode->i_sb); | |
963 | - return res; | |
964 | -} | |
965 | - | |
966 | -/* This function locks pages starting from @pos for @inode. | |
967 | - @num_pages pages are locked and stored in | |
968 | - @prepared_pages array. Also buffers are allocated for these pages. | |
969 | - First and last page of the region is read if it is overwritten only | |
970 | - partially. If last page did not exist before write (file hole or file | |
971 | - append), it is zeroed, then. | |
972 | - Returns number of unallocated blocks that should be allocated to cover | |
973 | - new file data.*/ | |
974 | -static int reiserfs_prepare_file_region_for_write(struct inode *inode | |
975 | - /* Inode of the file */ , | |
976 | - loff_t pos, /* position in the file */ | |
977 | - size_t num_pages, /* number of pages to | |
978 | - prepare */ | |
979 | - size_t write_bytes, /* Amount of bytes to be | |
980 | - overwritten from | |
981 | - @pos */ | |
982 | - struct page **prepared_pages /* pointer to array | |
983 | - where to store | |
984 | - prepared pages */ | |
985 | - ) | |
986 | -{ | |
987 | - int res = 0; // Return values of different functions we call. | |
988 | - unsigned long index = pos >> PAGE_CACHE_SHIFT; // Offset in file in pages. | |
989 | - int from = (pos & (PAGE_CACHE_SIZE - 1)); // Writing offset in first page | |
990 | - int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1; | |
991 | - /* offset of last modified byte in last | |
992 | - page */ | |
993 | - struct address_space *mapping = inode->i_mapping; // Pages are mapped here. | |
994 | - int i; // Simple counter | |
995 | - int blocks = 0; /* Return value (blocks that should be allocated) */ | |
996 | - struct buffer_head *bh, *head; // Current bufferhead and first bufferhead | |
997 | - // of a page. | |
998 | - unsigned block_start, block_end; // Starting and ending offsets of current | |
999 | - // buffer in the page. | |
1000 | - struct buffer_head *wait[2], **wait_bh = wait; // Buffers for page, if | |
1001 | - // Page appeared to be not up | |
1002 | - // to date. Note how we have | |
1003 | - // at most 2 buffers, this is | |
1004 | - // because we at most may | |
1005 | - // partially overwrite two | |
1006 | - // buffers for one page. One at // the beginning of write area | |
1007 | - // and one at the end. | |
1008 | - // Everything inthe middle gets // overwritten totally. | |
1009 | - | |
1010 | - struct cpu_key key; // cpu key of item that we are going to deal with | |
1011 | - struct item_head *ih = NULL; // pointer to item head that we are going to deal with | |
1012 | - struct buffer_head *itembuf = NULL; // Buffer head that contains items that we are going to deal with | |
1013 | - INITIALIZE_PATH(path); // path to item, that we are going to deal with. | |
1014 | - __le32 *item = NULL; // pointer to item we are going to deal with | |
1015 | - int item_pos = -1; /* Position in indirect item */ | |
1016 | - | |
1017 | - if (num_pages < 1) { | |
1018 | - reiserfs_warning(inode->i_sb, | |
1019 | - "green-9001: reiserfs_prepare_file_region_for_write " | |
1020 | - "called with zero number of pages to process"); | |
1021 | - return -EFAULT; | |
1022 | - } | |
1023 | - | |
1024 | - /* We have 2 loops for pages. In first loop we grab and lock the pages, so | |
1025 | - that nobody would touch these until we release the pages. Then | |
1026 | - we'd start to deal with mapping buffers to blocks. */ | |
1027 | - for (i = 0; i < num_pages; i++) { | |
1028 | - prepared_pages[i] = grab_cache_page(mapping, index + i); // locks the page | |
1029 | - if (!prepared_pages[i]) { | |
1030 | - res = -ENOMEM; | |
1031 | - goto failed_page_grabbing; | |
1032 | - } | |
1033 | - if (!page_has_buffers(prepared_pages[i])) | |
1034 | - create_empty_buffers(prepared_pages[i], | |
1035 | - inode->i_sb->s_blocksize, 0); | |
1036 | - } | |
1037 | - | |
1038 | - /* Let's count amount of blocks for a case where all the blocks | |
1039 | - overwritten are new (we will substract already allocated blocks later) */ | |
1040 | - if (num_pages > 2) | |
1041 | - /* These are full-overwritten pages so we count all the blocks in | |
1042 | - these pages are counted as needed to be allocated */ | |
1043 | - blocks = | |
1044 | - (num_pages - 2) << (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
1045 | - | |
1046 | - /* count blocks needed for first page (possibly partially written) */ | |
1047 | - blocks += ((PAGE_CACHE_SIZE - from) >> inode->i_blkbits) + !!(from & (inode->i_sb->s_blocksize - 1)); /* roundup */ | |
1048 | - | |
1049 | - /* Now we account for last page. If last page == first page (we | |
1050 | - overwrite only one page), we substract all the blocks past the | |
1051 | - last writing position in a page out of already calculated number | |
1052 | - of blocks */ | |
1053 | - blocks += ((num_pages > 1) << (PAGE_CACHE_SHIFT - inode->i_blkbits)) - | |
1054 | - ((PAGE_CACHE_SIZE - to) >> inode->i_blkbits); | |
1055 | - /* Note how we do not roundup here since partial blocks still | |
1056 | - should be allocated */ | |
1057 | - | |
1058 | - /* Now if all the write area lies past the file end, no point in | |
1059 | - maping blocks, since there is none, so we just zero out remaining | |
1060 | - parts of first and last pages in write area (if needed) */ | |
1061 | - if ((pos & ~((loff_t) PAGE_CACHE_SIZE - 1)) > inode->i_size) { | |
1062 | - if (from != 0) /* First page needs to be partially zeroed */ | |
1063 | - zero_user_page(prepared_pages[0], 0, from, KM_USER0); | |
1064 | - | |
1065 | - if (to != PAGE_CACHE_SIZE) /* Last page needs to be partially zeroed */ | |
1066 | - zero_user_page(prepared_pages[num_pages-1], to, | |
1067 | - PAGE_CACHE_SIZE - to, KM_USER0); | |
1068 | - | |
1069 | - /* Since all blocks are new - use already calculated value */ | |
1070 | - return blocks; | |
1071 | - } | |
1072 | - | |
1073 | - /* Well, since we write somewhere into the middle of a file, there is | |
1074 | - possibility we are writing over some already allocated blocks, so | |
1075 | - let's map these blocks and substract number of such blocks out of blocks | |
1076 | - we need to allocate (calculated above) */ | |
1077 | - /* Mask write position to start on blocksize, we do it out of the | |
1078 | - loop for performance reasons */ | |
1079 | - pos &= ~((loff_t) inode->i_sb->s_blocksize - 1); | |
1080 | - /* Set cpu key to the starting position in a file (on left block boundary) */ | |
1081 | - make_cpu_key(&key, inode, | |
1082 | - 1 + ((pos) & ~((loff_t) inode->i_sb->s_blocksize - 1)), | |
1083 | - TYPE_ANY, 3 /*key length */ ); | |
1084 | - | |
1085 | - reiserfs_write_lock(inode->i_sb); // We need that for at least search_by_key() | |
1086 | - for (i = 0; i < num_pages; i++) { | |
1087 | - | |
1088 | - head = page_buffers(prepared_pages[i]); | |
1089 | - /* For each buffer in the page */ | |
1090 | - for (bh = head, block_start = 0; bh != head || !block_start; | |
1091 | - block_start = block_end, bh = bh->b_this_page) { | |
1092 | - if (!bh) | |
1093 | - reiserfs_panic(inode->i_sb, | |
1094 | - "green-9002: Allocated but absent buffer for a page?"); | |
1095 | - /* Find where this buffer ends */ | |
1096 | - block_end = block_start + inode->i_sb->s_blocksize; | |
1097 | - if (i == 0 && block_end <= from) | |
1098 | - /* if this buffer is before requested data to map, skip it */ | |
1099 | - continue; | |
1100 | - | |
1101 | - if (i == num_pages - 1 && block_start >= to) { | |
1102 | - /* If this buffer is after requested data to map, abort | |
1103 | - processing of current page */ | |
1104 | - break; | |
1105 | - } | |
1106 | - | |
1107 | - if (buffer_mapped(bh) && bh->b_blocknr != 0) { | |
1108 | - /* This is optimisation for a case where buffer is mapped | |
1109 | - and have blocknumber assigned. In case significant amount | |
1110 | - of such buffers are present, we may avoid some amount | |
1111 | - of search_by_key calls. | |
1112 | - Probably it would be possible to move parts of this code | |
1113 | - out of BKL, but I afraid that would overcomplicate code | |
1114 | - without any noticeable benefit. | |
1115 | - */ | |
1116 | - item_pos++; | |
1117 | - /* Update the key */ | |
1118 | - set_cpu_key_k_offset(&key, | |
1119 | - cpu_key_k_offset(&key) + | |
1120 | - inode->i_sb->s_blocksize); | |
1121 | - blocks--; // Decrease the amount of blocks that need to be | |
1122 | - // allocated | |
1123 | - continue; // Go to the next buffer | |
1124 | - } | |
1125 | - | |
1126 | - if (!itembuf || /* if first iteration */ | |
1127 | - item_pos >= ih_item_len(ih) / UNFM_P_SIZE) { /* or if we progressed past the | |
1128 | - current unformatted_item */ | |
1129 | - /* Try to find next item */ | |
1130 | - res = | |
1131 | - search_for_position_by_key(inode->i_sb, | |
1132 | - &key, &path); | |
1133 | - /* Abort if no more items */ | |
1134 | - if (res != POSITION_FOUND) { | |
1135 | - /* make sure later loops don't use this item */ | |
1136 | - itembuf = NULL; | |
1137 | - item = NULL; | |
1138 | - break; | |
1139 | - } | |
1140 | - | |
1141 | - /* Update information about current indirect item */ | |
1142 | - itembuf = get_last_bh(&path); | |
1143 | - ih = get_ih(&path); | |
1144 | - item = get_item(&path); | |
1145 | - item_pos = path.pos_in_item; | |
1146 | - | |
1147 | - RFALSE(!is_indirect_le_ih(ih), | |
1148 | - "green-9003: indirect item expected"); | |
1149 | - } | |
1150 | - | |
1151 | - /* See if there is some block associated with the file | |
1152 | - at that position, map the buffer to this block */ | |
1153 | - if (get_block_num(item, item_pos)) { | |
1154 | - map_bh(bh, inode->i_sb, | |
1155 | - get_block_num(item, item_pos)); | |
1156 | - blocks--; // Decrease the amount of blocks that need to be | |
1157 | - // allocated | |
1158 | - } | |
1159 | - item_pos++; | |
1160 | - /* Update the key */ | |
1161 | - set_cpu_key_k_offset(&key, | |
1162 | - cpu_key_k_offset(&key) + | |
1163 | - inode->i_sb->s_blocksize); | |
1164 | - } | |
1165 | - } | |
1166 | - pathrelse(&path); // Free the path | |
1167 | - reiserfs_write_unlock(inode->i_sb); | |
1168 | - | |
1169 | - /* Now zero out unmappend buffers for the first and last pages of | |
1170 | - write area or issue read requests if page is mapped. */ | |
1171 | - /* First page, see if it is not uptodate */ | |
1172 | - if (!PageUptodate(prepared_pages[0])) { | |
1173 | - head = page_buffers(prepared_pages[0]); | |
1174 | - | |
1175 | - /* For each buffer in page */ | |
1176 | - for (bh = head, block_start = 0; bh != head || !block_start; | |
1177 | - block_start = block_end, bh = bh->b_this_page) { | |
1178 | - | |
1179 | - if (!bh) | |
1180 | - reiserfs_panic(inode->i_sb, | |
1181 | - "green-9002: Allocated but absent buffer for a page?"); | |
1182 | - /* Find where this buffer ends */ | |
1183 | - block_end = block_start + inode->i_sb->s_blocksize; | |
1184 | - if (block_end <= from) | |
1185 | - /* if this buffer is before requested data to map, skip it */ | |
1186 | - continue; | |
1187 | - if (block_start < from) { /* Aha, our partial buffer */ | |
1188 | - if (buffer_mapped(bh)) { /* If it is mapped, we need to | |
1189 | - issue READ request for it to | |
1190 | - not loose data */ | |
1191 | - ll_rw_block(READ, 1, &bh); | |
1192 | - *wait_bh++ = bh; | |
1193 | - } else { /* Not mapped, zero it */ | |
1194 | - zero_user_page(prepared_pages[0], | |
1195 | - block_start, | |
1196 | - from - block_start, KM_USER0); | |
1197 | - set_buffer_uptodate(bh); | |
1198 | - } | |
1199 | - } | |
1200 | - } | |
1201 | - } | |
1202 | - | |
1203 | - /* Last page, see if it is not uptodate, or if the last page is past the end of the file. */ | |
1204 | - if (!PageUptodate(prepared_pages[num_pages - 1]) || | |
1205 | - ((pos + write_bytes) >> PAGE_CACHE_SHIFT) > | |
1206 | - (inode->i_size >> PAGE_CACHE_SHIFT)) { | |
1207 | - head = page_buffers(prepared_pages[num_pages - 1]); | |
1208 | - | |
1209 | - /* for each buffer in page */ | |
1210 | - for (bh = head, block_start = 0; bh != head || !block_start; | |
1211 | - block_start = block_end, bh = bh->b_this_page) { | |
1212 | - | |
1213 | - if (!bh) | |
1214 | - reiserfs_panic(inode->i_sb, | |
1215 | - "green-9002: Allocated but absent buffer for a page?"); | |
1216 | - /* Find where this buffer ends */ | |
1217 | - block_end = block_start + inode->i_sb->s_blocksize; | |
1218 | - if (block_start >= to) | |
1219 | - /* if this buffer is after requested data to map, skip it */ | |
1220 | - break; | |
1221 | - if (block_end > to) { /* Aha, our partial buffer */ | |
1222 | - if (buffer_mapped(bh)) { /* If it is mapped, we need to | |
1223 | - issue READ request for it to | |
1224 | - not loose data */ | |
1225 | - ll_rw_block(READ, 1, &bh); | |
1226 | - *wait_bh++ = bh; | |
1227 | - } else { /* Not mapped, zero it */ | |
1228 | - zero_user_page(prepared_pages[num_pages-1], | |
1229 | - to, block_end - to, KM_USER0); | |
1230 | - set_buffer_uptodate(bh); | |
1231 | - } | |
1232 | - } | |
1233 | - } | |
1234 | - } | |
1235 | - | |
1236 | - /* Wait for read requests we made to happen, if necessary */ | |
1237 | - while (wait_bh > wait) { | |
1238 | - wait_on_buffer(*--wait_bh); | |
1239 | - if (!buffer_uptodate(*wait_bh)) { | |
1240 | - res = -EIO; | |
1241 | - goto failed_read; | |
1242 | - } | |
1243 | - } | |
1244 | - | |
1245 | - return blocks; | |
1246 | - failed_page_grabbing: | |
1247 | - num_pages = i; | |
1248 | - failed_read: | |
1249 | - reiserfs_unprepare_pages(prepared_pages, num_pages); | |
1250 | - return res; | |
1251 | -} | |
1252 | - | |
1253 | 225 | /* Write @count bytes at position @ppos in a file indicated by @file |
1254 | 226 | from the buffer @buf. |
1255 | 227 | |
1256 | 228 | |
... | ... | @@ -1284,14 +256,9 @@ |
1284 | 256 | * new current position before returning. */ |
1285 | 257 | ) |
1286 | 258 | { |
1287 | - size_t already_written = 0; // Number of bytes already written to the file. | |
1288 | - loff_t pos; // Current position in the file. | |
1289 | - ssize_t res; // return value of various functions that we call. | |
1290 | - int err = 0; | |
1291 | 259 | struct inode *inode = file->f_path.dentry->d_inode; // Inode of the file that we are writing to. |
1292 | 260 | /* To simplify coding at this time, we store |
1293 | 261 | locked pages in array for now */ |
1294 | - struct page *prepared_pages[REISERFS_WRITE_PAGES_AT_A_TIME]; | |
1295 | 262 | struct reiserfs_transaction_handle th; |
1296 | 263 | th.t_trans_id = 0; |
1297 | 264 | |
... | ... | @@ -1311,212 +278,7 @@ |
1311 | 278 | count = MAX_NON_LFS - (unsigned long)*ppos; |
1312 | 279 | } |
1313 | 280 | |
1314 | - if (file->f_flags & O_DIRECT) | |
1315 | - return do_sync_write(file, buf, count, ppos); | |
1316 | - | |
1317 | - if (unlikely((ssize_t) count < 0)) | |
1318 | - return -EINVAL; | |
1319 | - | |
1320 | - if (unlikely(!access_ok(VERIFY_READ, buf, count))) | |
1321 | - return -EFAULT; | |
1322 | - | |
1323 | - mutex_lock(&inode->i_mutex); // locks the entire file for just us | |
1324 | - | |
1325 | - pos = *ppos; | |
1326 | - | |
1327 | - /* Check if we can write to specified region of file, file | |
1328 | - is not overly big and this kind of stuff. Adjust pos and | |
1329 | - count, if needed */ | |
1330 | - res = generic_write_checks(file, &pos, &count, 0); | |
1331 | - if (res) | |
1332 | - goto out; | |
1333 | - | |
1334 | - if (count == 0) | |
1335 | - goto out; | |
1336 | - | |
1337 | - res = remove_suid(file->f_path.dentry); | |
1338 | - if (res) | |
1339 | - goto out; | |
1340 | - | |
1341 | - file_update_time(file); | |
1342 | - | |
1343 | - // Ok, we are done with all the checks. | |
1344 | - | |
1345 | - // Now we should start real work | |
1346 | - | |
1347 | - /* If we are going to write past the file's packed tail or if we are going | |
1348 | - to overwrite part of the tail, we need that tail to be converted into | |
1349 | - unformatted node */ | |
1350 | - res = reiserfs_check_for_tail_and_convert(inode, pos, count); | |
1351 | - if (res) | |
1352 | - goto out; | |
1353 | - | |
1354 | - while (count > 0) { | |
1355 | - /* This is the main loop in which we running until some error occures | |
1356 | - or until we write all of the data. */ | |
1357 | - size_t num_pages; /* amount of pages we are going to write this iteration */ | |
1358 | - size_t write_bytes; /* amount of bytes to write during this iteration */ | |
1359 | - size_t blocks_to_allocate; /* how much blocks we need to allocate for this iteration */ | |
1360 | - | |
1361 | - /* (pos & (PAGE_CACHE_SIZE-1)) is an idiom for offset into a page of pos */ | |
1362 | - num_pages = !!((pos + count) & (PAGE_CACHE_SIZE - 1)) + /* round up partial | |
1363 | - pages */ | |
1364 | - ((count + | |
1365 | - (pos & (PAGE_CACHE_SIZE - 1))) >> PAGE_CACHE_SHIFT); | |
1366 | - /* convert size to amount of | |
1367 | - pages */ | |
1368 | - reiserfs_write_lock(inode->i_sb); | |
1369 | - if (num_pages > REISERFS_WRITE_PAGES_AT_A_TIME | |
1370 | - || num_pages > reiserfs_can_fit_pages(inode->i_sb)) { | |
1371 | - /* If we were asked to write more data than we want to or if there | |
1372 | - is not that much space, then we shorten amount of data to write | |
1373 | - for this iteration. */ | |
1374 | - num_pages = | |
1375 | - min_t(size_t, REISERFS_WRITE_PAGES_AT_A_TIME, | |
1376 | - reiserfs_can_fit_pages(inode->i_sb)); | |
1377 | - /* Also we should not forget to set size in bytes accordingly */ | |
1378 | - write_bytes = (num_pages << PAGE_CACHE_SHIFT) - | |
1379 | - (pos & (PAGE_CACHE_SIZE - 1)); | |
1380 | - /* If position is not on the | |
1381 | - start of the page, we need | |
1382 | - to substract the offset | |
1383 | - within page */ | |
1384 | - } else | |
1385 | - write_bytes = count; | |
1386 | - | |
1387 | - /* reserve the blocks to be allocated later, so that later on | |
1388 | - we still have the space to write the blocks to */ | |
1389 | - reiserfs_claim_blocks_to_be_allocated(inode->i_sb, | |
1390 | - num_pages << | |
1391 | - (PAGE_CACHE_SHIFT - | |
1392 | - inode->i_blkbits)); | |
1393 | - reiserfs_write_unlock(inode->i_sb); | |
1394 | - | |
1395 | - if (!num_pages) { /* If we do not have enough space even for a single page... */ | |
1396 | - if (pos > | |
1397 | - inode->i_size + inode->i_sb->s_blocksize - | |
1398 | - (pos & (inode->i_sb->s_blocksize - 1))) { | |
1399 | - res = -ENOSPC; | |
1400 | - break; // In case we are writing past the end of the last file block, break. | |
1401 | - } | |
1402 | - // Otherwise we are possibly overwriting the file, so | |
1403 | - // let's set write size to be equal or less than blocksize. | |
1404 | - // This way we get it correctly for file holes. | |
1405 | - // But overwriting files on absolutelly full volumes would not | |
1406 | - // be very efficient. Well, people are not supposed to fill | |
1407 | - // 100% of disk space anyway. | |
1408 | - write_bytes = | |
1409 | - min_t(size_t, count, | |
1410 | - inode->i_sb->s_blocksize - | |
1411 | - (pos & (inode->i_sb->s_blocksize - 1))); | |
1412 | - num_pages = 1; | |
1413 | - // No blocks were claimed before, so do it now. | |
1414 | - reiserfs_claim_blocks_to_be_allocated(inode->i_sb, | |
1415 | - 1 << | |
1416 | - (PAGE_CACHE_SHIFT | |
1417 | - - | |
1418 | - inode-> | |
1419 | - i_blkbits)); | |
1420 | - } | |
1421 | - | |
1422 | - /* Prepare for writing into the region, read in all the | |
1423 | - partially overwritten pages, if needed. And lock the pages, | |
1424 | - so that nobody else can access these until we are done. | |
1425 | - We get number of actual blocks needed as a result. */ | |
1426 | - res = reiserfs_prepare_file_region_for_write(inode, pos, | |
1427 | - num_pages, | |
1428 | - write_bytes, | |
1429 | - prepared_pages); | |
1430 | - if (res < 0) { | |
1431 | - reiserfs_release_claimed_blocks(inode->i_sb, | |
1432 | - num_pages << | |
1433 | - (PAGE_CACHE_SHIFT - | |
1434 | - inode->i_blkbits)); | |
1435 | - break; | |
1436 | - } | |
1437 | - | |
1438 | - blocks_to_allocate = res; | |
1439 | - | |
1440 | - /* First we correct our estimate of how many blocks we need */ | |
1441 | - reiserfs_release_claimed_blocks(inode->i_sb, | |
1442 | - (num_pages << | |
1443 | - (PAGE_CACHE_SHIFT - | |
1444 | - inode->i_sb-> | |
1445 | - s_blocksize_bits)) - | |
1446 | - blocks_to_allocate); | |
1447 | - | |
1448 | - if (blocks_to_allocate > 0) { /*We only allocate blocks if we need to */ | |
1449 | - /* Fill in all the possible holes and append the file if needed */ | |
1450 | - res = | |
1451 | - reiserfs_allocate_blocks_for_region(&th, inode, pos, | |
1452 | - num_pages, | |
1453 | - write_bytes, | |
1454 | - prepared_pages, | |
1455 | - blocks_to_allocate); | |
1456 | - } | |
1457 | - | |
1458 | - /* well, we have allocated the blocks, so it is time to free | |
1459 | - the reservation we made earlier. */ | |
1460 | - reiserfs_release_claimed_blocks(inode->i_sb, | |
1461 | - blocks_to_allocate); | |
1462 | - if (res) { | |
1463 | - reiserfs_unprepare_pages(prepared_pages, num_pages); | |
1464 | - break; | |
1465 | - } | |
1466 | - | |
1467 | -/* NOTE that allocating blocks and filling blocks can be done in reverse order | |
1468 | - and probably we would do that just to get rid of garbage in files after a | |
1469 | - crash */ | |
1470 | - | |
1471 | - /* Copy data from user-supplied buffer to file's pages */ | |
1472 | - res = | |
1473 | - reiserfs_copy_from_user_to_file_region(pos, num_pages, | |
1474 | - write_bytes, | |
1475 | - prepared_pages, buf); | |
1476 | - if (res) { | |
1477 | - reiserfs_unprepare_pages(prepared_pages, num_pages); | |
1478 | - break; | |
1479 | - } | |
1480 | - | |
1481 | - /* Send the pages to disk and unlock them. */ | |
1482 | - res = | |
1483 | - reiserfs_submit_file_region_for_write(&th, inode, pos, | |
1484 | - num_pages, | |
1485 | - write_bytes, | |
1486 | - prepared_pages); | |
1487 | - if (res) | |
1488 | - break; | |
1489 | - | |
1490 | - already_written += write_bytes; | |
1491 | - buf += write_bytes; | |
1492 | - *ppos = pos += write_bytes; | |
1493 | - count -= write_bytes; | |
1494 | - balance_dirty_pages_ratelimited_nr(inode->i_mapping, num_pages); | |
1495 | - } | |
1496 | - | |
1497 | - /* this is only true on error */ | |
1498 | - if (th.t_trans_id) { | |
1499 | - reiserfs_write_lock(inode->i_sb); | |
1500 | - err = journal_end(&th, th.t_super, th.t_blocks_allocated); | |
1501 | - reiserfs_write_unlock(inode->i_sb); | |
1502 | - if (err) { | |
1503 | - res = err; | |
1504 | - goto out; | |
1505 | - } | |
1506 | - } | |
1507 | - | |
1508 | - if (likely(res >= 0) && | |
1509 | - (unlikely((file->f_flags & O_SYNC) || IS_SYNC(inode)))) | |
1510 | - res = generic_osync_inode(inode, file->f_mapping, | |
1511 | - OSYNC_METADATA | OSYNC_DATA); | |
1512 | - | |
1513 | - mutex_unlock(&inode->i_mutex); | |
1514 | - reiserfs_async_progress_wait(inode->i_sb); | |
1515 | - return (already_written != 0) ? already_written : res; | |
1516 | - | |
1517 | - out: | |
1518 | - mutex_unlock(&inode->i_mutex); // unlock the file on exit. | |
1519 | - return res; | |
281 | + return do_sync_write(file, buf, count, ppos); | |
1520 | 282 | } |
1521 | 283 | |
1522 | 284 | const struct file_operations reiserfs_file_operations = { |