Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1 | /* |
| 2 | drbd_bitmap.c |
| 3 | |
| 4 | This file is part of DRBD by Philipp Reisner and Lars Ellenberg. |
| 5 | |
| 6 | Copyright (C) 2004-2008, LINBIT Information Technologies GmbH. |
| 7 | Copyright (C) 2004-2008, Philipp Reisner <philipp.reisner@linbit.com>. |
| 8 | Copyright (C) 2004-2008, Lars Ellenberg <lars.ellenberg@linbit.com>. |
| 9 | |
| 10 | drbd is free software; you can redistribute it and/or modify |
| 11 | it under the terms of the GNU General Public License as published by |
| 12 | the Free Software Foundation; either version 2, or (at your option) |
| 13 | any later version. |
| 14 | |
| 15 | drbd is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | GNU General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU General Public License |
| 21 | along with drbd; see the file COPYING. If not, write to |
| 22 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. |
| 23 | */ |
| 24 | |
| 25 | #include <linux/bitops.h> |
| 26 | #include <linux/vmalloc.h> |
| 27 | #include <linux/string.h> |
| 28 | #include <linux/drbd.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 29 | #include <linux/slab.h> |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 30 | #include <asm/kmap_types.h> |
| 31 | #include "drbd_int.h" |
| 32 | |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 33 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 34 | /* OPAQUE outside this file! |
| 35 | * interface defined in drbd_int.h |
| 36 | |
| 37 | * convention: |
| 38 | * function name drbd_bm_... => used elsewhere, "public". |
| 39 | * function name bm_... => internal to implementation, "private". |
| 40 | |
| 41 | * Note that since find_first_bit returns int, at the current granularity of |
| 42 | * the bitmap (4KB per byte), this implementation "only" supports up to |
| 43 | * 1<<(32+12) == 16 TB... |
| 44 | */ |
| 45 | |
| 46 | /* |
| 47 | * NOTE |
| 48 | * Access to the *bm_pages is protected by bm_lock. |
| 49 | * It is safe to read the other members within the lock. |
| 50 | * |
| 51 | * drbd_bm_set_bits is called from bio_endio callbacks, |
| 52 | * We may be called with irq already disabled, |
| 53 | * so we need spin_lock_irqsave(). |
| 54 | * And we need the kmap_atomic. |
| 55 | */ |
| 56 | struct drbd_bitmap { |
| 57 | struct page **bm_pages; |
| 58 | spinlock_t bm_lock; |
| 59 | /* WARNING unsigned long bm_*: |
| 60 | * 32bit number of bit offset is just enough for 512 MB bitmap. |
| 61 | * it will blow up if we make the bitmap bigger... |
| 62 | * not that it makes much sense to have a bitmap that large, |
| 63 | * rather change the granularity to 16k or 64k or something. |
| 64 | * (that implies other problems, however...) |
| 65 | */ |
| 66 | unsigned long bm_set; /* nr of set bits; THINK maybe atomic_t? */ |
| 67 | unsigned long bm_bits; |
| 68 | size_t bm_words; |
| 69 | size_t bm_number_of_pages; |
| 70 | sector_t bm_dev_capacity; |
Thomas Gleixner | 8a03ae2 | 2010-01-29 20:39:07 +0000 | [diff] [blame] | 71 | struct mutex bm_change; /* serializes resize operations */ |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 72 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 73 | wait_queue_head_t bm_io_wait; /* used to serialize IO of single pages */ |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 74 | |
| 75 | unsigned long bm_flags; |
| 76 | |
| 77 | /* debugging aid, in case we are still racy somewhere */ |
| 78 | char *bm_why; |
| 79 | struct task_struct *bm_task; |
| 80 | }; |
| 81 | |
| 82 | /* definition of bits in bm_flags */ |
| 83 | #define BM_LOCKED 0 |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 84 | // #define BM_MD_IO_ERROR 1 unused now. |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 85 | #define BM_P_VMALLOCED 2 |
| 86 | |
Philipp Reisner | b4ee79d | 2010-04-01 09:57:40 +0200 | [diff] [blame] | 87 | static int __bm_change_bits_to(struct drbd_conf *mdev, const unsigned long s, |
Philipp Reisner | fd76438 | 2010-04-01 09:57:40 +0200 | [diff] [blame] | 88 | unsigned long e, int val, const enum km_type km); |
| 89 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 90 | static int bm_is_locked(struct drbd_bitmap *b) |
| 91 | { |
| 92 | return test_bit(BM_LOCKED, &b->bm_flags); |
| 93 | } |
| 94 | |
| 95 | #define bm_print_lock_info(m) __bm_print_lock_info(m, __func__) |
| 96 | static void __bm_print_lock_info(struct drbd_conf *mdev, const char *func) |
| 97 | { |
| 98 | struct drbd_bitmap *b = mdev->bitmap; |
| 99 | if (!__ratelimit(&drbd_ratelimit_state)) |
| 100 | return; |
| 101 | dev_err(DEV, "FIXME %s in %s, bitmap locked for '%s' by %s\n", |
| 102 | current == mdev->receiver.task ? "receiver" : |
| 103 | current == mdev->asender.task ? "asender" : |
| 104 | current == mdev->worker.task ? "worker" : current->comm, |
| 105 | func, b->bm_why ?: "?", |
| 106 | b->bm_task == mdev->receiver.task ? "receiver" : |
| 107 | b->bm_task == mdev->asender.task ? "asender" : |
| 108 | b->bm_task == mdev->worker.task ? "worker" : "?"); |
| 109 | } |
| 110 | |
| 111 | void drbd_bm_lock(struct drbd_conf *mdev, char *why) |
| 112 | { |
| 113 | struct drbd_bitmap *b = mdev->bitmap; |
| 114 | int trylock_failed; |
| 115 | |
| 116 | if (!b) { |
| 117 | dev_err(DEV, "FIXME no bitmap in drbd_bm_lock!?\n"); |
| 118 | return; |
| 119 | } |
| 120 | |
Thomas Gleixner | 8a03ae2 | 2010-01-29 20:39:07 +0000 | [diff] [blame] | 121 | trylock_failed = !mutex_trylock(&b->bm_change); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 122 | |
| 123 | if (trylock_failed) { |
| 124 | dev_warn(DEV, "%s going to '%s' but bitmap already locked for '%s' by %s\n", |
| 125 | current == mdev->receiver.task ? "receiver" : |
| 126 | current == mdev->asender.task ? "asender" : |
| 127 | current == mdev->worker.task ? "worker" : current->comm, |
| 128 | why, b->bm_why ?: "?", |
| 129 | b->bm_task == mdev->receiver.task ? "receiver" : |
| 130 | b->bm_task == mdev->asender.task ? "asender" : |
| 131 | b->bm_task == mdev->worker.task ? "worker" : "?"); |
Thomas Gleixner | 8a03ae2 | 2010-01-29 20:39:07 +0000 | [diff] [blame] | 132 | mutex_lock(&b->bm_change); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 133 | } |
| 134 | if (__test_and_set_bit(BM_LOCKED, &b->bm_flags)) |
| 135 | dev_err(DEV, "FIXME bitmap already locked in bm_lock\n"); |
| 136 | |
| 137 | b->bm_why = why; |
| 138 | b->bm_task = current; |
| 139 | } |
| 140 | |
| 141 | void drbd_bm_unlock(struct drbd_conf *mdev) |
| 142 | { |
| 143 | struct drbd_bitmap *b = mdev->bitmap; |
| 144 | if (!b) { |
| 145 | dev_err(DEV, "FIXME no bitmap in drbd_bm_unlock!?\n"); |
| 146 | return; |
| 147 | } |
| 148 | |
| 149 | if (!__test_and_clear_bit(BM_LOCKED, &mdev->bitmap->bm_flags)) |
| 150 | dev_err(DEV, "FIXME bitmap not locked in bm_unlock\n"); |
| 151 | |
| 152 | b->bm_why = NULL; |
| 153 | b->bm_task = NULL; |
Thomas Gleixner | 8a03ae2 | 2010-01-29 20:39:07 +0000 | [diff] [blame] | 154 | mutex_unlock(&b->bm_change); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 155 | } |
| 156 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 157 | /* we store some "meta" info about our pages in page->private */ |
| 158 | /* at a granularity of 4k storage per bitmap bit: |
| 159 | * one peta byte storage: 1<<50 byte, 1<<38 * 4k storage blocks |
| 160 | * 1<<38 bits, |
| 161 | * 1<<23 4k bitmap pages. |
| 162 | * Use 24 bits as page index, covers 2 peta byte storage |
| 163 | * at a granularity of 4k per bit. |
| 164 | * Used to report the failed page idx on io error from the endio handlers. |
| 165 | */ |
| 166 | #define BM_PAGE_IDX_MASK ((1UL<<24)-1) |
| 167 | /* this page is currently read in, or written back */ |
| 168 | #define BM_PAGE_IO_LOCK 31 |
| 169 | /* if there has been an IO error for this page */ |
| 170 | #define BM_PAGE_IO_ERROR 30 |
| 171 | /* this is to be able to intelligently skip disk IO, |
| 172 | * set if bits have been set since last IO. */ |
| 173 | #define BM_PAGE_NEED_WRITEOUT 29 |
| 174 | /* to mark for lazy writeout once syncer cleared all clearable bits, |
| 175 | * we if bits have been cleared since last IO. */ |
| 176 | #define BM_PAGE_LAZY_WRITEOUT 28 |
| 177 | |
| 178 | /* store_page_idx uses non-atomic assingment. It is only used directly after |
| 179 | * allocating the page. All other bm_set_page_* and bm_clear_page_* need to |
| 180 | * use atomic bit manipulation, as set_out_of_sync (and therefore bitmap |
| 181 | * changes) may happen from various contexts, and wait_on_bit/wake_up_bit |
| 182 | * requires it all to be atomic as well. */ |
| 183 | static void bm_store_page_idx(struct page *page, unsigned long idx) |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 184 | { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 185 | BUG_ON(0 != (idx & ~BM_PAGE_IDX_MASK)); |
| 186 | page_private(page) |= idx; |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 187 | } |
| 188 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 189 | static unsigned long bm_page_to_idx(struct page *page) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 190 | { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 191 | return page_private(page) & BM_PAGE_IDX_MASK; |
| 192 | } |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 193 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 194 | /* As is very unlikely that the same page is under IO from more than one |
| 195 | * context, we can get away with a bit per page and one wait queue per bitmap. |
| 196 | */ |
| 197 | static void bm_page_lock_io(struct drbd_conf *mdev, int page_nr) |
| 198 | { |
| 199 | struct drbd_bitmap *b = mdev->bitmap; |
| 200 | void *addr = &page_private(b->bm_pages[page_nr]); |
| 201 | wait_event(b->bm_io_wait, !test_and_set_bit(BM_PAGE_IO_LOCK, addr)); |
| 202 | } |
| 203 | |
| 204 | static void bm_page_unlock_io(struct drbd_conf *mdev, int page_nr) |
| 205 | { |
| 206 | struct drbd_bitmap *b = mdev->bitmap; |
| 207 | void *addr = &page_private(b->bm_pages[page_nr]); |
| 208 | clear_bit(BM_PAGE_IO_LOCK, addr); |
| 209 | smp_mb__after_clear_bit(); |
| 210 | wake_up(&mdev->bitmap->bm_io_wait); |
| 211 | } |
| 212 | |
| 213 | /* set _before_ submit_io, so it may be reset due to being changed |
| 214 | * while this page is in flight... will get submitted later again */ |
| 215 | static void bm_set_page_unchanged(struct page *page) |
| 216 | { |
| 217 | /* use cmpxchg? */ |
| 218 | clear_bit(BM_PAGE_NEED_WRITEOUT, &page_private(page)); |
| 219 | clear_bit(BM_PAGE_LAZY_WRITEOUT, &page_private(page)); |
| 220 | } |
| 221 | |
| 222 | static void bm_set_page_need_writeout(struct page *page) |
| 223 | { |
| 224 | set_bit(BM_PAGE_NEED_WRITEOUT, &page_private(page)); |
| 225 | } |
| 226 | |
| 227 | static int bm_test_page_unchanged(struct page *page) |
| 228 | { |
| 229 | volatile const unsigned long *addr = &page_private(page); |
| 230 | return (*addr & ((1UL<<BM_PAGE_NEED_WRITEOUT)|(1UL<<BM_PAGE_LAZY_WRITEOUT))) == 0; |
| 231 | } |
| 232 | |
| 233 | static void bm_set_page_io_err(struct page *page) |
| 234 | { |
| 235 | set_bit(BM_PAGE_IO_ERROR, &page_private(page)); |
| 236 | } |
| 237 | |
| 238 | static void bm_clear_page_io_err(struct page *page) |
| 239 | { |
| 240 | clear_bit(BM_PAGE_IO_ERROR, &page_private(page)); |
| 241 | } |
| 242 | |
| 243 | static void bm_set_page_lazy_writeout(struct page *page) |
| 244 | { |
| 245 | set_bit(BM_PAGE_LAZY_WRITEOUT, &page_private(page)); |
| 246 | } |
| 247 | |
| 248 | static int bm_test_page_lazy_writeout(struct page *page) |
| 249 | { |
| 250 | return test_bit(BM_PAGE_LAZY_WRITEOUT, &page_private(page)); |
| 251 | } |
| 252 | |
| 253 | /* on a 32bit box, this would allow for exactly (2<<38) bits. */ |
| 254 | static unsigned int bm_word_to_page_idx(struct drbd_bitmap *b, unsigned long long_nr) |
| 255 | { |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 256 | /* page_nr = (word*sizeof(long)) >> PAGE_SHIFT; */ |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 257 | unsigned int page_nr = long_nr >> (PAGE_SHIFT - LN2_BPL + 3); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 258 | BUG_ON(page_nr >= b->bm_number_of_pages); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 259 | return page_nr; |
| 260 | } |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 261 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 262 | static unsigned int bm_bit_to_page_idx(struct drbd_bitmap *b, u64 bitnr) |
| 263 | { |
| 264 | /* page_nr = (bitnr/8) >> PAGE_SHIFT; */ |
| 265 | unsigned int page_nr = bitnr >> (PAGE_SHIFT + 3); |
| 266 | BUG_ON(page_nr >= b->bm_number_of_pages); |
| 267 | return page_nr; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 268 | } |
| 269 | |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 270 | static unsigned long *__bm_map_pidx(struct drbd_bitmap *b, unsigned int idx, const enum km_type km) |
| 271 | { |
| 272 | struct page *page = b->bm_pages[idx]; |
| 273 | return (unsigned long *) kmap_atomic(page, km); |
| 274 | } |
| 275 | |
| 276 | static unsigned long *bm_map_pidx(struct drbd_bitmap *b, unsigned int idx) |
| 277 | { |
| 278 | return __bm_map_pidx(b, idx, KM_IRQ1); |
| 279 | } |
| 280 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 281 | static void __bm_unmap(unsigned long *p_addr, const enum km_type km) |
| 282 | { |
| 283 | kunmap_atomic(p_addr, km); |
| 284 | }; |
| 285 | |
| 286 | static void bm_unmap(unsigned long *p_addr) |
| 287 | { |
| 288 | return __bm_unmap(p_addr, KM_IRQ1); |
| 289 | } |
| 290 | |
| 291 | /* long word offset of _bitmap_ sector */ |
| 292 | #define S2W(s) ((s)<<(BM_EXT_SHIFT-BM_BLOCK_SHIFT-LN2_BPL)) |
| 293 | /* word offset from start of bitmap to word number _in_page_ |
| 294 | * modulo longs per page |
| 295 | #define MLPP(X) ((X) % (PAGE_SIZE/sizeof(long)) |
| 296 | hm, well, Philipp thinks gcc might not optimze the % into & (... - 1) |
| 297 | so do it explicitly: |
| 298 | */ |
| 299 | #define MLPP(X) ((X) & ((PAGE_SIZE/sizeof(long))-1)) |
| 300 | |
| 301 | /* Long words per page */ |
| 302 | #define LWPP (PAGE_SIZE/sizeof(long)) |
| 303 | |
| 304 | /* |
| 305 | * actually most functions herein should take a struct drbd_bitmap*, not a |
| 306 | * struct drbd_conf*, but for the debug macros I like to have the mdev around |
| 307 | * to be able to report device specific. |
| 308 | */ |
| 309 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 310 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 311 | static void bm_free_pages(struct page **pages, unsigned long number) |
| 312 | { |
| 313 | unsigned long i; |
| 314 | if (!pages) |
| 315 | return; |
| 316 | |
| 317 | for (i = 0; i < number; i++) { |
| 318 | if (!pages[i]) { |
| 319 | printk(KERN_ALERT "drbd: bm_free_pages tried to free " |
| 320 | "a NULL pointer; i=%lu n=%lu\n", |
| 321 | i, number); |
| 322 | continue; |
| 323 | } |
| 324 | __free_page(pages[i]); |
| 325 | pages[i] = NULL; |
| 326 | } |
| 327 | } |
| 328 | |
| 329 | static void bm_vk_free(void *ptr, int v) |
| 330 | { |
| 331 | if (v) |
| 332 | vfree(ptr); |
| 333 | else |
| 334 | kfree(ptr); |
| 335 | } |
| 336 | |
| 337 | /* |
| 338 | * "have" and "want" are NUMBER OF PAGES. |
| 339 | */ |
| 340 | static struct page **bm_realloc_pages(struct drbd_bitmap *b, unsigned long want) |
| 341 | { |
| 342 | struct page **old_pages = b->bm_pages; |
| 343 | struct page **new_pages, *page; |
| 344 | unsigned int i, bytes, vmalloced = 0; |
| 345 | unsigned long have = b->bm_number_of_pages; |
| 346 | |
| 347 | BUG_ON(have == 0 && old_pages != NULL); |
| 348 | BUG_ON(have != 0 && old_pages == NULL); |
| 349 | |
| 350 | if (have == want) |
| 351 | return old_pages; |
| 352 | |
| 353 | /* Trying kmalloc first, falling back to vmalloc. |
| 354 | * GFP_KERNEL is ok, as this is done when a lower level disk is |
| 355 | * "attached" to the drbd. Context is receiver thread or cqueue |
| 356 | * thread. As we have no disk yet, we are not in the IO path, |
| 357 | * not even the IO path of the peer. */ |
| 358 | bytes = sizeof(struct page *)*want; |
| 359 | new_pages = kmalloc(bytes, GFP_KERNEL); |
| 360 | if (!new_pages) { |
| 361 | new_pages = vmalloc(bytes); |
| 362 | if (!new_pages) |
| 363 | return NULL; |
| 364 | vmalloced = 1; |
| 365 | } |
| 366 | |
| 367 | memset(new_pages, 0, bytes); |
| 368 | if (want >= have) { |
| 369 | for (i = 0; i < have; i++) |
| 370 | new_pages[i] = old_pages[i]; |
| 371 | for (; i < want; i++) { |
| 372 | page = alloc_page(GFP_HIGHUSER); |
| 373 | if (!page) { |
| 374 | bm_free_pages(new_pages + have, i - have); |
| 375 | bm_vk_free(new_pages, vmalloced); |
| 376 | return NULL; |
| 377 | } |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 378 | /* we want to know which page it is |
| 379 | * from the endio handlers */ |
| 380 | bm_store_page_idx(page, i); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 381 | new_pages[i] = page; |
| 382 | } |
| 383 | } else { |
| 384 | for (i = 0; i < want; i++) |
| 385 | new_pages[i] = old_pages[i]; |
| 386 | /* NOT HERE, we are outside the spinlock! |
| 387 | bm_free_pages(old_pages + want, have - want); |
| 388 | */ |
| 389 | } |
| 390 | |
| 391 | if (vmalloced) |
| 392 | set_bit(BM_P_VMALLOCED, &b->bm_flags); |
| 393 | else |
| 394 | clear_bit(BM_P_VMALLOCED, &b->bm_flags); |
| 395 | |
| 396 | return new_pages; |
| 397 | } |
| 398 | |
| 399 | /* |
| 400 | * called on driver init only. TODO call when a device is created. |
| 401 | * allocates the drbd_bitmap, and stores it in mdev->bitmap. |
| 402 | */ |
| 403 | int drbd_bm_init(struct drbd_conf *mdev) |
| 404 | { |
| 405 | struct drbd_bitmap *b = mdev->bitmap; |
| 406 | WARN_ON(b != NULL); |
| 407 | b = kzalloc(sizeof(struct drbd_bitmap), GFP_KERNEL); |
| 408 | if (!b) |
| 409 | return -ENOMEM; |
| 410 | spin_lock_init(&b->bm_lock); |
Thomas Gleixner | 8a03ae2 | 2010-01-29 20:39:07 +0000 | [diff] [blame] | 411 | mutex_init(&b->bm_change); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 412 | init_waitqueue_head(&b->bm_io_wait); |
| 413 | |
| 414 | mdev->bitmap = b; |
| 415 | |
| 416 | return 0; |
| 417 | } |
| 418 | |
| 419 | sector_t drbd_bm_capacity(struct drbd_conf *mdev) |
| 420 | { |
| 421 | ERR_IF(!mdev->bitmap) return 0; |
| 422 | return mdev->bitmap->bm_dev_capacity; |
| 423 | } |
| 424 | |
| 425 | /* called on driver unload. TODO: call when a device is destroyed. |
| 426 | */ |
| 427 | void drbd_bm_cleanup(struct drbd_conf *mdev) |
| 428 | { |
| 429 | ERR_IF (!mdev->bitmap) return; |
| 430 | bm_free_pages(mdev->bitmap->bm_pages, mdev->bitmap->bm_number_of_pages); |
| 431 | bm_vk_free(mdev->bitmap->bm_pages, test_bit(BM_P_VMALLOCED, &mdev->bitmap->bm_flags)); |
| 432 | kfree(mdev->bitmap); |
| 433 | mdev->bitmap = NULL; |
| 434 | } |
| 435 | |
| 436 | /* |
| 437 | * since (b->bm_bits % BITS_PER_LONG) != 0, |
| 438 | * this masks out the remaining bits. |
| 439 | * Returns the number of bits cleared. |
| 440 | */ |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 441 | #define BITS_PER_PAGE (1UL << (PAGE_SHIFT + 3)) |
| 442 | #define BITS_PER_PAGE_MASK (BITS_PER_PAGE - 1) |
| 443 | #define BITS_PER_LONG_MASK (BITS_PER_LONG - 1) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 444 | static int bm_clear_surplus(struct drbd_bitmap *b) |
| 445 | { |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 446 | unsigned long mask; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 447 | unsigned long *p_addr, *bm; |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 448 | int tmp; |
| 449 | int cleared = 0; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 450 | |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 451 | /* number of bits modulo bits per page */ |
| 452 | tmp = (b->bm_bits & BITS_PER_PAGE_MASK); |
| 453 | /* mask the used bits of the word containing the last bit */ |
| 454 | mask = (1UL << (tmp & BITS_PER_LONG_MASK)) -1; |
| 455 | /* bitmap is always stored little endian, |
| 456 | * on disk and in core memory alike */ |
| 457 | mask = cpu_to_lel(mask); |
| 458 | |
| 459 | /* because of the "extra long to catch oob access" we allocate in |
| 460 | * drbd_bm_resize, bm_number_of_pages -1 is not necessarily the page |
| 461 | * containing the last _relevant_ bitmap word */ |
| 462 | p_addr = bm_map_pidx(b, bm_bit_to_page_idx(b, b->bm_bits - 1)); |
| 463 | bm = p_addr + (tmp/BITS_PER_LONG); |
| 464 | if (mask) { |
| 465 | /* If mask != 0, we are not exactly aligned, so bm now points |
| 466 | * to the long containing the last bit. |
| 467 | * If mask == 0, bm already points to the word immediately |
| 468 | * after the last (long word aligned) bit. */ |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 469 | cleared = hweight_long(*bm & ~mask); |
| 470 | *bm &= mask; |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 471 | bm++; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 472 | } |
| 473 | |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 474 | if (BITS_PER_LONG == 32 && ((bm - p_addr) & 1) == 1) { |
| 475 | /* on a 32bit arch, we may need to zero out |
| 476 | * a padding long to align with a 64bit remote */ |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 477 | cleared += hweight_long(*bm); |
| 478 | *bm = 0; |
| 479 | } |
| 480 | bm_unmap(p_addr); |
| 481 | return cleared; |
| 482 | } |
| 483 | |
| 484 | static void bm_set_surplus(struct drbd_bitmap *b) |
| 485 | { |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 486 | unsigned long mask; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 487 | unsigned long *p_addr, *bm; |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 488 | int tmp; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 489 | |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 490 | /* number of bits modulo bits per page */ |
| 491 | tmp = (b->bm_bits & BITS_PER_PAGE_MASK); |
| 492 | /* mask the used bits of the word containing the last bit */ |
| 493 | mask = (1UL << (tmp & BITS_PER_LONG_MASK)) -1; |
| 494 | /* bitmap is always stored little endian, |
| 495 | * on disk and in core memory alike */ |
| 496 | mask = cpu_to_lel(mask); |
| 497 | |
| 498 | /* because of the "extra long to catch oob access" we allocate in |
| 499 | * drbd_bm_resize, bm_number_of_pages -1 is not necessarily the page |
| 500 | * containing the last _relevant_ bitmap word */ |
| 501 | p_addr = bm_map_pidx(b, bm_bit_to_page_idx(b, b->bm_bits - 1)); |
| 502 | bm = p_addr + (tmp/BITS_PER_LONG); |
| 503 | if (mask) { |
| 504 | /* If mask != 0, we are not exactly aligned, so bm now points |
| 505 | * to the long containing the last bit. |
| 506 | * If mask == 0, bm already points to the word immediately |
| 507 | * after the last (long word aligned) bit. */ |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 508 | *bm |= ~mask; |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 509 | bm++; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 510 | } |
| 511 | |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 512 | if (BITS_PER_LONG == 32 && ((bm - p_addr) & 1) == 1) { |
| 513 | /* on a 32bit arch, we may need to zero out |
| 514 | * a padding long to align with a 64bit remote */ |
| 515 | *bm = ~0UL; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 516 | } |
| 517 | bm_unmap(p_addr); |
| 518 | } |
| 519 | |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 520 | static unsigned long bm_count_bits(struct drbd_bitmap *b) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 521 | { |
| 522 | unsigned long *p_addr, *bm, offset = 0; |
| 523 | unsigned long bits = 0; |
| 524 | unsigned long i, do_now; |
Lars Ellenberg | 7777a8b | 2010-12-15 23:21:39 +0100 | [diff] [blame] | 525 | unsigned long words; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 526 | |
Lars Ellenberg | 7777a8b | 2010-12-15 23:21:39 +0100 | [diff] [blame] | 527 | /* due to 64bit alignment, the last long on a 32bit arch |
| 528 | * may be not used at all. The last used long will likely |
| 529 | * be only partially used, always. Don't count those bits, |
| 530 | * but mask them out. */ |
| 531 | words = (b->bm_bits + BITS_PER_LONG - 1) >> LN2_BPL; |
| 532 | |
| 533 | while (offset < words) { |
| 534 | i = do_now = min_t(size_t, words-offset, LWPP); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 535 | p_addr = __bm_map_pidx(b, bm_word_to_page_idx(b, offset), KM_USER0); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 536 | bm = p_addr + MLPP(offset); |
| 537 | while (i--) { |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 538 | bits += hweight_long(*bm++); |
| 539 | } |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 540 | offset += do_now; |
Lars Ellenberg | 7777a8b | 2010-12-15 23:21:39 +0100 | [diff] [blame] | 541 | if (offset == words) { |
| 542 | /* last word may only be partially used, |
| 543 | * see also bm_clear_surplus. */ |
| 544 | i = (1UL << (b->bm_bits & (BITS_PER_LONG-1))) -1; |
| 545 | if (i) { |
| 546 | bits -= hweight_long(p_addr[do_now-1] & ~i); |
| 547 | p_addr[do_now-1] &= i; |
| 548 | } |
| 549 | /* 32bit arch, may have an unused padding long */ |
| 550 | if (words != b->bm_words) |
| 551 | p_addr[do_now] = 0; |
| 552 | } |
| 553 | __bm_unmap(p_addr, KM_USER0); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 554 | cond_resched(); |
| 555 | } |
| 556 | |
| 557 | return bits; |
| 558 | } |
| 559 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 560 | /* offset and len in long words.*/ |
| 561 | static void bm_memset(struct drbd_bitmap *b, size_t offset, int c, size_t len) |
| 562 | { |
| 563 | unsigned long *p_addr, *bm; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 564 | unsigned int idx; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 565 | size_t do_now, end; |
| 566 | |
| 567 | #define BM_SECTORS_PER_BIT (BM_BLOCK_SIZE/512) |
| 568 | |
| 569 | end = offset + len; |
| 570 | |
| 571 | if (end > b->bm_words) { |
| 572 | printk(KERN_ALERT "drbd: bm_memset end > bm_words\n"); |
| 573 | return; |
| 574 | } |
| 575 | |
| 576 | while (offset < end) { |
| 577 | do_now = min_t(size_t, ALIGN(offset + 1, LWPP), end) - offset; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 578 | idx = bm_word_to_page_idx(b, offset); |
| 579 | p_addr = bm_map_pidx(b, idx); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 580 | bm = p_addr + MLPP(offset); |
| 581 | if (bm+do_now > p_addr + LWPP) { |
| 582 | printk(KERN_ALERT "drbd: BUG BUG BUG! p_addr:%p bm:%p do_now:%d\n", |
| 583 | p_addr, bm, (int)do_now); |
| 584 | break; /* breaks to after catch_oob_access_end() only! */ |
| 585 | } |
| 586 | memset(bm, c, do_now * sizeof(long)); |
| 587 | bm_unmap(p_addr); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 588 | bm_set_page_need_writeout(b->bm_pages[idx]); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 589 | offset += do_now; |
| 590 | } |
| 591 | } |
| 592 | |
| 593 | /* |
| 594 | * make sure the bitmap has enough room for the attached storage, |
| 595 | * if necessary, resize. |
| 596 | * called whenever we may have changed the device size. |
| 597 | * returns -ENOMEM if we could not allocate enough memory, 0 on success. |
| 598 | * In case this is actually a resize, we copy the old bitmap into the new one. |
| 599 | * Otherwise, the bitmap is initialized to all bits set. |
| 600 | */ |
Philipp Reisner | 02d9a94 | 2010-03-24 16:23:03 +0100 | [diff] [blame] | 601 | int drbd_bm_resize(struct drbd_conf *mdev, sector_t capacity, int set_new_bits) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 602 | { |
| 603 | struct drbd_bitmap *b = mdev->bitmap; |
| 604 | unsigned long bits, words, owords, obits, *p_addr, *bm; |
| 605 | unsigned long want, have, onpages; /* number of pages */ |
| 606 | struct page **npages, **opages = NULL; |
| 607 | int err = 0, growing; |
| 608 | int opages_vmalloced; |
| 609 | |
| 610 | ERR_IF(!b) return -ENOMEM; |
| 611 | |
| 612 | drbd_bm_lock(mdev, "resize"); |
| 613 | |
| 614 | dev_info(DEV, "drbd_bm_resize called with capacity == %llu\n", |
| 615 | (unsigned long long)capacity); |
| 616 | |
| 617 | if (capacity == b->bm_dev_capacity) |
| 618 | goto out; |
| 619 | |
| 620 | opages_vmalloced = test_bit(BM_P_VMALLOCED, &b->bm_flags); |
| 621 | |
| 622 | if (capacity == 0) { |
| 623 | spin_lock_irq(&b->bm_lock); |
| 624 | opages = b->bm_pages; |
| 625 | onpages = b->bm_number_of_pages; |
| 626 | owords = b->bm_words; |
| 627 | b->bm_pages = NULL; |
| 628 | b->bm_number_of_pages = |
| 629 | b->bm_set = |
| 630 | b->bm_bits = |
| 631 | b->bm_words = |
| 632 | b->bm_dev_capacity = 0; |
| 633 | spin_unlock_irq(&b->bm_lock); |
| 634 | bm_free_pages(opages, onpages); |
| 635 | bm_vk_free(opages, opages_vmalloced); |
| 636 | goto out; |
| 637 | } |
| 638 | bits = BM_SECT_TO_BIT(ALIGN(capacity, BM_SECT_PER_BIT)); |
| 639 | |
| 640 | /* if we would use |
| 641 | words = ALIGN(bits,BITS_PER_LONG) >> LN2_BPL; |
| 642 | a 32bit host could present the wrong number of words |
| 643 | to a 64bit host. |
| 644 | */ |
| 645 | words = ALIGN(bits, 64) >> LN2_BPL; |
| 646 | |
| 647 | if (get_ldev(mdev)) { |
| 648 | D_ASSERT((u64)bits <= (((u64)mdev->ldev->md.md_size_sect-MD_BM_OFFSET) << 12)); |
| 649 | put_ldev(mdev); |
| 650 | } |
| 651 | |
| 652 | /* one extra long to catch off by one errors */ |
| 653 | want = ALIGN((words+1)*sizeof(long), PAGE_SIZE) >> PAGE_SHIFT; |
| 654 | have = b->bm_number_of_pages; |
| 655 | if (want == have) { |
| 656 | D_ASSERT(b->bm_pages != NULL); |
| 657 | npages = b->bm_pages; |
| 658 | } else { |
Andreas Gruenbacher | 0cf9d27 | 2010-12-07 10:43:29 +0100 | [diff] [blame] | 659 | if (drbd_insert_fault(mdev, DRBD_FAULT_BM_ALLOC)) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 660 | npages = NULL; |
| 661 | else |
| 662 | npages = bm_realloc_pages(b, want); |
| 663 | } |
| 664 | |
| 665 | if (!npages) { |
| 666 | err = -ENOMEM; |
| 667 | goto out; |
| 668 | } |
| 669 | |
| 670 | spin_lock_irq(&b->bm_lock); |
| 671 | opages = b->bm_pages; |
| 672 | owords = b->bm_words; |
| 673 | obits = b->bm_bits; |
| 674 | |
| 675 | growing = bits > obits; |
Philipp Reisner | 5223671 | 2010-04-28 14:46:57 +0200 | [diff] [blame] | 676 | if (opages && growing && set_new_bits) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 677 | bm_set_surplus(b); |
| 678 | |
| 679 | b->bm_pages = npages; |
| 680 | b->bm_number_of_pages = want; |
| 681 | b->bm_bits = bits; |
| 682 | b->bm_words = words; |
| 683 | b->bm_dev_capacity = capacity; |
| 684 | |
| 685 | if (growing) { |
Philipp Reisner | 02d9a94 | 2010-03-24 16:23:03 +0100 | [diff] [blame] | 686 | if (set_new_bits) { |
| 687 | bm_memset(b, owords, 0xff, words-owords); |
| 688 | b->bm_set += bits - obits; |
| 689 | } else |
| 690 | bm_memset(b, owords, 0x00, words-owords); |
| 691 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 692 | } |
| 693 | |
| 694 | if (want < have) { |
| 695 | /* implicit: (opages != NULL) && (opages != npages) */ |
| 696 | bm_free_pages(opages + want, have - want); |
| 697 | } |
| 698 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 699 | p_addr = bm_map_pidx(b, bm_word_to_page_idx(b, words)); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 700 | bm = p_addr + MLPP(words); |
| 701 | *bm = DRBD_MAGIC; |
| 702 | bm_unmap(p_addr); |
| 703 | |
| 704 | (void)bm_clear_surplus(b); |
| 705 | |
| 706 | spin_unlock_irq(&b->bm_lock); |
| 707 | if (opages != npages) |
| 708 | bm_vk_free(opages, opages_vmalloced); |
| 709 | if (!growing) |
| 710 | b->bm_set = bm_count_bits(b); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 711 | dev_info(DEV, "resync bitmap: bits=%lu words=%lu pages=%lu\n", bits, words, want); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 712 | |
| 713 | out: |
| 714 | drbd_bm_unlock(mdev); |
| 715 | return err; |
| 716 | } |
| 717 | |
| 718 | /* inherently racy: |
| 719 | * if not protected by other means, return value may be out of date when |
| 720 | * leaving this function... |
| 721 | * we still need to lock it, since it is important that this returns |
| 722 | * bm_set == 0 precisely. |
| 723 | * |
| 724 | * maybe bm_set should be atomic_t ? |
| 725 | */ |
Philipp Reisner | 0778286 | 2010-08-31 12:00:50 +0200 | [diff] [blame] | 726 | unsigned long _drbd_bm_total_weight(struct drbd_conf *mdev) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 727 | { |
| 728 | struct drbd_bitmap *b = mdev->bitmap; |
| 729 | unsigned long s; |
| 730 | unsigned long flags; |
| 731 | |
| 732 | ERR_IF(!b) return 0; |
| 733 | ERR_IF(!b->bm_pages) return 0; |
| 734 | |
| 735 | spin_lock_irqsave(&b->bm_lock, flags); |
| 736 | s = b->bm_set; |
| 737 | spin_unlock_irqrestore(&b->bm_lock, flags); |
| 738 | |
| 739 | return s; |
| 740 | } |
| 741 | |
| 742 | unsigned long drbd_bm_total_weight(struct drbd_conf *mdev) |
| 743 | { |
| 744 | unsigned long s; |
| 745 | /* if I don't have a disk, I don't know about out-of-sync status */ |
| 746 | if (!get_ldev_if_state(mdev, D_NEGOTIATING)) |
| 747 | return 0; |
| 748 | s = _drbd_bm_total_weight(mdev); |
| 749 | put_ldev(mdev); |
| 750 | return s; |
| 751 | } |
| 752 | |
| 753 | size_t drbd_bm_words(struct drbd_conf *mdev) |
| 754 | { |
| 755 | struct drbd_bitmap *b = mdev->bitmap; |
| 756 | ERR_IF(!b) return 0; |
| 757 | ERR_IF(!b->bm_pages) return 0; |
| 758 | |
| 759 | return b->bm_words; |
| 760 | } |
| 761 | |
| 762 | unsigned long drbd_bm_bits(struct drbd_conf *mdev) |
| 763 | { |
| 764 | struct drbd_bitmap *b = mdev->bitmap; |
| 765 | ERR_IF(!b) return 0; |
| 766 | |
| 767 | return b->bm_bits; |
| 768 | } |
| 769 | |
| 770 | /* merge number words from buffer into the bitmap starting at offset. |
| 771 | * buffer[i] is expected to be little endian unsigned long. |
| 772 | * bitmap must be locked by drbd_bm_lock. |
| 773 | * currently only used from receive_bitmap. |
| 774 | */ |
| 775 | void drbd_bm_merge_lel(struct drbd_conf *mdev, size_t offset, size_t number, |
| 776 | unsigned long *buffer) |
| 777 | { |
| 778 | struct drbd_bitmap *b = mdev->bitmap; |
| 779 | unsigned long *p_addr, *bm; |
| 780 | unsigned long word, bits; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 781 | unsigned int idx; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 782 | size_t end, do_now; |
| 783 | |
| 784 | end = offset + number; |
| 785 | |
| 786 | ERR_IF(!b) return; |
| 787 | ERR_IF(!b->bm_pages) return; |
| 788 | if (number == 0) |
| 789 | return; |
| 790 | WARN_ON(offset >= b->bm_words); |
| 791 | WARN_ON(end > b->bm_words); |
| 792 | |
| 793 | spin_lock_irq(&b->bm_lock); |
| 794 | while (offset < end) { |
| 795 | do_now = min_t(size_t, ALIGN(offset+1, LWPP), end) - offset; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 796 | idx = bm_word_to_page_idx(b, offset); |
| 797 | p_addr = bm_map_pidx(b, idx); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 798 | bm = p_addr + MLPP(offset); |
| 799 | offset += do_now; |
| 800 | while (do_now--) { |
| 801 | bits = hweight_long(*bm); |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 802 | word = *bm | *buffer++; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 803 | *bm++ = word; |
| 804 | b->bm_set += hweight_long(word) - bits; |
| 805 | } |
| 806 | bm_unmap(p_addr); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 807 | bm_set_page_need_writeout(b->bm_pages[idx]); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 808 | } |
| 809 | /* with 32bit <-> 64bit cross-platform connect |
| 810 | * this is only correct for current usage, |
| 811 | * where we _know_ that we are 64 bit aligned, |
| 812 | * and know that this function is used in this way, too... |
| 813 | */ |
| 814 | if (end == b->bm_words) |
| 815 | b->bm_set -= bm_clear_surplus(b); |
| 816 | |
| 817 | spin_unlock_irq(&b->bm_lock); |
| 818 | } |
| 819 | |
| 820 | /* copy number words from the bitmap starting at offset into the buffer. |
| 821 | * buffer[i] will be little endian unsigned long. |
| 822 | */ |
| 823 | void drbd_bm_get_lel(struct drbd_conf *mdev, size_t offset, size_t number, |
| 824 | unsigned long *buffer) |
| 825 | { |
| 826 | struct drbd_bitmap *b = mdev->bitmap; |
| 827 | unsigned long *p_addr, *bm; |
| 828 | size_t end, do_now; |
| 829 | |
| 830 | end = offset + number; |
| 831 | |
| 832 | ERR_IF(!b) return; |
| 833 | ERR_IF(!b->bm_pages) return; |
| 834 | |
| 835 | spin_lock_irq(&b->bm_lock); |
| 836 | if ((offset >= b->bm_words) || |
| 837 | (end > b->bm_words) || |
| 838 | (number <= 0)) |
| 839 | dev_err(DEV, "offset=%lu number=%lu bm_words=%lu\n", |
| 840 | (unsigned long) offset, |
| 841 | (unsigned long) number, |
| 842 | (unsigned long) b->bm_words); |
| 843 | else { |
| 844 | while (offset < end) { |
| 845 | do_now = min_t(size_t, ALIGN(offset+1, LWPP), end) - offset; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 846 | p_addr = bm_map_pidx(b, bm_word_to_page_idx(b, offset)); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 847 | bm = p_addr + MLPP(offset); |
| 848 | offset += do_now; |
| 849 | while (do_now--) |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 850 | *buffer++ = *bm++; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 851 | bm_unmap(p_addr); |
| 852 | } |
| 853 | } |
| 854 | spin_unlock_irq(&b->bm_lock); |
| 855 | } |
| 856 | |
| 857 | /* set all bits in the bitmap */ |
| 858 | void drbd_bm_set_all(struct drbd_conf *mdev) |
| 859 | { |
| 860 | struct drbd_bitmap *b = mdev->bitmap; |
| 861 | ERR_IF(!b) return; |
| 862 | ERR_IF(!b->bm_pages) return; |
| 863 | |
| 864 | spin_lock_irq(&b->bm_lock); |
| 865 | bm_memset(b, 0, 0xff, b->bm_words); |
| 866 | (void)bm_clear_surplus(b); |
| 867 | b->bm_set = b->bm_bits; |
| 868 | spin_unlock_irq(&b->bm_lock); |
| 869 | } |
| 870 | |
| 871 | /* clear all bits in the bitmap */ |
| 872 | void drbd_bm_clear_all(struct drbd_conf *mdev) |
| 873 | { |
| 874 | struct drbd_bitmap *b = mdev->bitmap; |
| 875 | ERR_IF(!b) return; |
| 876 | ERR_IF(!b->bm_pages) return; |
| 877 | |
| 878 | spin_lock_irq(&b->bm_lock); |
| 879 | bm_memset(b, 0, 0, b->bm_words); |
| 880 | b->bm_set = 0; |
| 881 | spin_unlock_irq(&b->bm_lock); |
| 882 | } |
| 883 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 884 | struct bm_aio_ctx { |
| 885 | struct drbd_conf *mdev; |
| 886 | atomic_t in_flight; |
| 887 | wait_queue_head_t io_wait; |
| 888 | unsigned flags; |
| 889 | #define BM_AIO_COPY_PAGES 1 |
| 890 | int error; |
| 891 | }; |
| 892 | |
| 893 | /* bv_page may be a copy, or may be the original */ |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 894 | static void bm_async_io_complete(struct bio *bio, int error) |
| 895 | { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 896 | struct bm_aio_ctx *ctx = bio->bi_private; |
| 897 | struct drbd_conf *mdev = ctx->mdev; |
| 898 | struct drbd_bitmap *b = mdev->bitmap; |
| 899 | unsigned int idx = bm_page_to_idx(bio->bi_io_vec[0].bv_page); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 900 | int uptodate = bio_flagged(bio, BIO_UPTODATE); |
| 901 | |
| 902 | |
| 903 | /* strange behavior of some lower level drivers... |
| 904 | * fail the request by clearing the uptodate flag, |
| 905 | * but do not return any error?! |
| 906 | * do we want to WARN() on this? */ |
| 907 | if (!error && !uptodate) |
| 908 | error = -EIO; |
| 909 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 910 | if (!bm_test_page_unchanged(b->bm_pages[idx])) |
| 911 | dev_info(DEV, "bitmap page idx %u changed during IO!\n", idx); |
| 912 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 913 | if (error) { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 914 | /* ctx error will hold the completed-last non-zero error code, |
| 915 | * in case error codes differ. */ |
| 916 | ctx->error = error; |
| 917 | bm_set_page_io_err(b->bm_pages[idx]); |
| 918 | /* Not identical to on disk version of it. |
| 919 | * Is BM_PAGE_IO_ERROR enough? */ |
| 920 | if (__ratelimit(&drbd_ratelimit_state)) |
| 921 | dev_err(DEV, "IO ERROR %d on bitmap page idx %u\n", |
| 922 | error, idx); |
| 923 | } else { |
| 924 | bm_clear_page_io_err(b->bm_pages[idx]); |
| 925 | dynamic_dev_dbg(DEV, "bitmap page idx %u completed\n", idx); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 926 | } |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 927 | |
| 928 | bm_page_unlock_io(mdev, idx); |
| 929 | |
| 930 | /* FIXME give back to page pool */ |
| 931 | if (ctx->flags & BM_AIO_COPY_PAGES) |
| 932 | put_page(bio->bi_io_vec[0].bv_page); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 933 | |
| 934 | bio_put(bio); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 935 | |
| 936 | if (atomic_dec_and_test(&ctx->in_flight)) |
| 937 | wake_up(&ctx->io_wait); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 938 | } |
| 939 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 940 | static void bm_page_io_async(struct bm_aio_ctx *ctx, int page_nr, int rw) __must_hold(local) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 941 | { |
| 942 | /* we are process context. we always get a bio */ |
| 943 | struct bio *bio = bio_alloc(GFP_KERNEL, 1); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 944 | struct drbd_conf *mdev = ctx->mdev; |
| 945 | struct drbd_bitmap *b = mdev->bitmap; |
| 946 | struct page *page; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 947 | unsigned int len; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 948 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 949 | sector_t on_disk_sector = |
| 950 | mdev->ldev->md.md_offset + mdev->ldev->md.bm_offset; |
| 951 | on_disk_sector += ((sector_t)page_nr) << (PAGE_SHIFT-9); |
| 952 | |
| 953 | /* this might happen with very small |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 954 | * flexible external meta data device, |
| 955 | * or with PAGE_SIZE > 4k */ |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 956 | len = min_t(unsigned int, PAGE_SIZE, |
| 957 | (drbd_md_last_sector(mdev->ldev) - on_disk_sector + 1)<<9); |
| 958 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 959 | /* serialize IO on this page */ |
| 960 | bm_page_lock_io(mdev, page_nr); |
| 961 | /* before memcpy and submit, |
| 962 | * so it can be redirtied any time */ |
| 963 | bm_set_page_unchanged(b->bm_pages[page_nr]); |
| 964 | |
| 965 | if (ctx->flags & BM_AIO_COPY_PAGES) { |
| 966 | /* FIXME alloc_page is good enough for now, but actually needs |
| 967 | * to use pre-allocated page pool */ |
| 968 | void *src, *dest; |
| 969 | page = alloc_page(__GFP_HIGHMEM|__GFP_WAIT); |
| 970 | dest = kmap_atomic(page, KM_USER0); |
| 971 | src = kmap_atomic(b->bm_pages[page_nr], KM_USER1); |
| 972 | memcpy(dest, src, PAGE_SIZE); |
| 973 | kunmap_atomic(src, KM_USER1); |
| 974 | kunmap_atomic(dest, KM_USER0); |
| 975 | bm_store_page_idx(page, page_nr); |
| 976 | } else |
| 977 | page = b->bm_pages[page_nr]; |
| 978 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 979 | bio->bi_bdev = mdev->ldev->md_bdev; |
| 980 | bio->bi_sector = on_disk_sector; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 981 | bio_add_page(bio, page, len, 0); |
| 982 | bio->bi_private = ctx; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 983 | bio->bi_end_io = bm_async_io_complete; |
| 984 | |
Andreas Gruenbacher | 0cf9d27 | 2010-12-07 10:43:29 +0100 | [diff] [blame] | 985 | if (drbd_insert_fault(mdev, (rw & WRITE) ? DRBD_FAULT_MD_WR : DRBD_FAULT_MD_RD)) { |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 986 | bio->bi_rw |= rw; |
| 987 | bio_endio(bio, -EIO); |
| 988 | } else { |
| 989 | submit_bio(rw, bio); |
| 990 | } |
| 991 | } |
| 992 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 993 | /* |
| 994 | * bm_rw: read/write the whole bitmap from/to its on disk location. |
| 995 | */ |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 996 | static int bm_rw(struct drbd_conf *mdev, int rw, unsigned lazy_writeout_upper_idx) __must_hold(local) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 997 | { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 998 | struct bm_aio_ctx ctx = |
| 999 | { .flags = lazy_writeout_upper_idx ? BM_AIO_COPY_PAGES : 0 }; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1000 | struct drbd_bitmap *b = mdev->bitmap; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1001 | int last_page, i, count = 0; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1002 | unsigned long now; |
| 1003 | char ppb[10]; |
| 1004 | int err = 0; |
| 1005 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1006 | /* |
| 1007 | * We are protected against bitmap disappearing/resizing by holding an |
| 1008 | * ldev reference (caller must have called get_ldev()). |
| 1009 | * For read/write, we are protected against changes to the bitmap by |
| 1010 | * the bitmap lock (see drbd_bitmap_io). |
| 1011 | * For lazy writeout, we don't care for ongoing changes to the bitmap, |
| 1012 | * as we submit copies of pages anyways. |
| 1013 | */ |
| 1014 | if (!ctx.flags) |
| 1015 | WARN_ON(!bm_is_locked(b)); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1016 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1017 | /* because of the "extra long to catch oob access" we allocate in |
| 1018 | * drbd_bm_resize, bm_number_of_pages -1 is not necessarily the page |
| 1019 | * containing the last _relevant_ bitmap word */ |
| 1020 | last_page = bm_word_to_page_idx(b, b->bm_words - 1); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1021 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1022 | now = jiffies; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1023 | ctx.mdev = mdev; |
| 1024 | atomic_set(&ctx.in_flight, 1); /* one extra ref */ |
| 1025 | init_waitqueue_head(&ctx.io_wait); |
| 1026 | ctx.error = 0; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1027 | |
| 1028 | /* let the layers below us try to merge these bios... */ |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1029 | for (i = 0; i <= last_page; i++) { |
| 1030 | /* ignore completely unchanged pages */ |
| 1031 | if (lazy_writeout_upper_idx && i == lazy_writeout_upper_idx) |
| 1032 | break; |
| 1033 | if (rw & WRITE) { |
| 1034 | if (bm_test_page_unchanged(b->bm_pages[i])) { |
| 1035 | dynamic_dev_dbg(DEV, "skipped bm write for idx %u\n", i); |
| 1036 | continue; |
| 1037 | } |
| 1038 | /* during lazy writeout, |
| 1039 | * ignore those pages not marked for lazy writeout. */ |
| 1040 | if (lazy_writeout_upper_idx && |
| 1041 | !bm_test_page_lazy_writeout(b->bm_pages[i])) { |
| 1042 | dynamic_dev_dbg(DEV, "skipped bm lazy write for idx %u\n", i); |
| 1043 | continue; |
| 1044 | } |
| 1045 | } |
| 1046 | atomic_inc(&ctx.in_flight); |
| 1047 | bm_page_io_async(&ctx, i, rw); |
| 1048 | ++count; |
| 1049 | cond_resched(); |
| 1050 | } |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1051 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1052 | atomic_dec(&ctx.in_flight); /* drop the extra ref */ |
| 1053 | wait_event(ctx.io_wait, atomic_read(&ctx.in_flight) == 0); |
| 1054 | dev_info(DEV, "bitmap %s of %u pages took %lu jiffies\n", |
| 1055 | rw == WRITE ? "WRITE" : "READ", |
| 1056 | count, jiffies - now); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1057 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1058 | if (ctx.error) { |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1059 | dev_alert(DEV, "we had at least one MD IO ERROR during bitmap IO\n"); |
Andreas Gruenbacher | 81e8465 | 2010-12-09 15:03:57 +0100 | [diff] [blame] | 1060 | drbd_chk_io_error(mdev, 1, true); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1061 | err = -EIO; /* ctx.error ? */ |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1062 | } |
| 1063 | |
| 1064 | now = jiffies; |
| 1065 | if (rw == WRITE) { |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1066 | drbd_md_flush(mdev); |
| 1067 | } else /* rw == READ */ { |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 1068 | b->bm_set = bm_count_bits(b); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1069 | dev_info(DEV, "recounting of set bits took additional %lu jiffies\n", |
| 1070 | jiffies - now); |
| 1071 | } |
| 1072 | now = b->bm_set; |
| 1073 | |
| 1074 | dev_info(DEV, "%s (%lu bits) marked out-of-sync by on disk bit-map.\n", |
| 1075 | ppsize(ppb, now << (BM_BLOCK_SHIFT-10)), now); |
| 1076 | |
| 1077 | return err; |
| 1078 | } |
| 1079 | |
| 1080 | /** |
| 1081 | * drbd_bm_read() - Read the whole bitmap from its on disk location. |
| 1082 | * @mdev: DRBD device. |
| 1083 | */ |
| 1084 | int drbd_bm_read(struct drbd_conf *mdev) __must_hold(local) |
| 1085 | { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1086 | return bm_rw(mdev, READ, 0); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1087 | } |
| 1088 | |
| 1089 | /** |
| 1090 | * drbd_bm_write() - Write the whole bitmap to its on disk location. |
| 1091 | * @mdev: DRBD device. |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1092 | * |
| 1093 | * Will only write pages that have changed since last IO. |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1094 | */ |
| 1095 | int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local) |
| 1096 | { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1097 | return bm_rw(mdev, WRITE, 0); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1098 | } |
| 1099 | |
| 1100 | /** |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1101 | * drbd_bm_lazy_write_out() - Write bitmap pages 0 to @upper_idx-1, if they have changed. |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1102 | * @mdev: DRBD device. |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1103 | * @upper_idx: 0: write all changed pages; +ve: page index to stop scanning for changed pages |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1104 | */ |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1105 | int drbd_bm_write_lazy(struct drbd_conf *mdev, unsigned upper_idx) __must_hold(local) |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1106 | { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1107 | return bm_rw(mdev, WRITE, upper_idx); |
| 1108 | } |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1109 | |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1110 | |
| 1111 | /** |
| 1112 | * drbd_bm_write_page: Writes a PAGE_SIZE aligned piece of bitmap |
| 1113 | * @mdev: DRBD device. |
| 1114 | * @idx: bitmap page index |
| 1115 | * |
| 1116 | * We don't want to special case on logical_block_size of the underlaying |
| 1117 | * device, so we submit PAGE_SIZE aligned pieces containing the requested enr. |
| 1118 | * Note that on "most" systems, PAGE_SIZE is 4k. |
| 1119 | */ |
| 1120 | int drbd_bm_write_page(struct drbd_conf *mdev, unsigned int idx) __must_hold(local) |
| 1121 | { |
| 1122 | struct bm_aio_ctx ctx = { .flags = BM_AIO_COPY_PAGES, }; |
| 1123 | |
| 1124 | if (bm_test_page_unchanged(mdev->bitmap->bm_pages[idx])) { |
| 1125 | dev_info(DEV, "skipped bm page write for idx %u\n", idx); |
| 1126 | return 0; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1127 | } |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1128 | |
| 1129 | ctx.mdev = mdev; |
| 1130 | atomic_set(&ctx.in_flight, 1); |
| 1131 | init_waitqueue_head(&ctx.io_wait); |
| 1132 | |
| 1133 | bm_page_io_async(&ctx, idx, WRITE_SYNC); |
| 1134 | wait_event(ctx.io_wait, atomic_read(&ctx.in_flight) == 0); |
| 1135 | |
| 1136 | if (ctx.error) |
| 1137 | drbd_chk_io_error(mdev, 1, true); |
| 1138 | /* that should force detach, so the in memory bitmap will be |
| 1139 | * gone in a moment as well. */ |
| 1140 | |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1141 | mdev->bm_writ_cnt++; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1142 | return ctx.error; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1143 | } |
| 1144 | |
| 1145 | /* NOTE |
| 1146 | * find_first_bit returns int, we return unsigned long. |
| 1147 | * should not make much difference anyways, but ... |
| 1148 | * |
| 1149 | * this returns a bit number, NOT a sector! |
| 1150 | */ |
| 1151 | #define BPP_MASK ((1UL << (PAGE_SHIFT+3)) - 1) |
| 1152 | static unsigned long __bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo, |
| 1153 | const int find_zero_bit, const enum km_type km) |
| 1154 | { |
| 1155 | struct drbd_bitmap *b = mdev->bitmap; |
| 1156 | unsigned long i = -1UL; |
| 1157 | unsigned long *p_addr; |
| 1158 | unsigned long bit_offset; /* bit offset of the mapped page. */ |
| 1159 | |
| 1160 | if (bm_fo > b->bm_bits) { |
| 1161 | dev_err(DEV, "bm_fo=%lu bm_bits=%lu\n", bm_fo, b->bm_bits); |
| 1162 | } else { |
| 1163 | while (bm_fo < b->bm_bits) { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1164 | /* bit offset of the first bit in the page */ |
| 1165 | bit_offset = bm_fo & ~BPP_MASK; |
| 1166 | p_addr = __bm_map_pidx(b, bm_bit_to_page_idx(b, bm_fo), km); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1167 | |
| 1168 | if (find_zero_bit) |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 1169 | i = generic_find_next_zero_le_bit(p_addr, PAGE_SIZE*8, bm_fo & BPP_MASK); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1170 | else |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 1171 | i = generic_find_next_le_bit(p_addr, PAGE_SIZE*8, bm_fo & BPP_MASK); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1172 | |
| 1173 | __bm_unmap(p_addr, km); |
| 1174 | if (i < PAGE_SIZE*8) { |
| 1175 | i = bit_offset + i; |
| 1176 | if (i >= b->bm_bits) |
| 1177 | break; |
| 1178 | goto found; |
| 1179 | } |
| 1180 | bm_fo = bit_offset + PAGE_SIZE*8; |
| 1181 | } |
| 1182 | i = -1UL; |
| 1183 | } |
| 1184 | found: |
| 1185 | return i; |
| 1186 | } |
| 1187 | |
| 1188 | static unsigned long bm_find_next(struct drbd_conf *mdev, |
| 1189 | unsigned long bm_fo, const int find_zero_bit) |
| 1190 | { |
| 1191 | struct drbd_bitmap *b = mdev->bitmap; |
| 1192 | unsigned long i = -1UL; |
| 1193 | |
| 1194 | ERR_IF(!b) return i; |
| 1195 | ERR_IF(!b->bm_pages) return i; |
| 1196 | |
| 1197 | spin_lock_irq(&b->bm_lock); |
| 1198 | if (bm_is_locked(b)) |
| 1199 | bm_print_lock_info(mdev); |
| 1200 | |
| 1201 | i = __bm_find_next(mdev, bm_fo, find_zero_bit, KM_IRQ1); |
| 1202 | |
| 1203 | spin_unlock_irq(&b->bm_lock); |
| 1204 | return i; |
| 1205 | } |
| 1206 | |
| 1207 | unsigned long drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo) |
| 1208 | { |
| 1209 | return bm_find_next(mdev, bm_fo, 0); |
| 1210 | } |
| 1211 | |
| 1212 | #if 0 |
| 1213 | /* not yet needed for anything. */ |
| 1214 | unsigned long drbd_bm_find_next_zero(struct drbd_conf *mdev, unsigned long bm_fo) |
| 1215 | { |
| 1216 | return bm_find_next(mdev, bm_fo, 1); |
| 1217 | } |
| 1218 | #endif |
| 1219 | |
| 1220 | /* does not spin_lock_irqsave. |
| 1221 | * you must take drbd_bm_lock() first */ |
| 1222 | unsigned long _drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo) |
| 1223 | { |
| 1224 | /* WARN_ON(!bm_is_locked(mdev)); */ |
| 1225 | return __bm_find_next(mdev, bm_fo, 0, KM_USER1); |
| 1226 | } |
| 1227 | |
| 1228 | unsigned long _drbd_bm_find_next_zero(struct drbd_conf *mdev, unsigned long bm_fo) |
| 1229 | { |
| 1230 | /* WARN_ON(!bm_is_locked(mdev)); */ |
| 1231 | return __bm_find_next(mdev, bm_fo, 1, KM_USER1); |
| 1232 | } |
| 1233 | |
| 1234 | /* returns number of bits actually changed. |
| 1235 | * for val != 0, we change 0 -> 1, return code positive |
| 1236 | * for val == 0, we change 1 -> 0, return code negative |
| 1237 | * wants bitnr, not sector. |
| 1238 | * expected to be called for only a few bits (e - s about BITS_PER_LONG). |
| 1239 | * Must hold bitmap lock already. */ |
Philipp Reisner | b4ee79d | 2010-04-01 09:57:40 +0200 | [diff] [blame] | 1240 | static int __bm_change_bits_to(struct drbd_conf *mdev, const unsigned long s, |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1241 | unsigned long e, int val, const enum km_type km) |
| 1242 | { |
| 1243 | struct drbd_bitmap *b = mdev->bitmap; |
| 1244 | unsigned long *p_addr = NULL; |
| 1245 | unsigned long bitnr; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1246 | unsigned int last_page_nr = -1U; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1247 | int c = 0; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1248 | int changed_total = 0; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1249 | |
| 1250 | if (e >= b->bm_bits) { |
| 1251 | dev_err(DEV, "ASSERT FAILED: bit_s=%lu bit_e=%lu bm_bits=%lu\n", |
| 1252 | s, e, b->bm_bits); |
| 1253 | e = b->bm_bits ? b->bm_bits -1 : 0; |
| 1254 | } |
| 1255 | for (bitnr = s; bitnr <= e; bitnr++) { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1256 | unsigned int page_nr = bm_bit_to_page_idx(b, bitnr); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1257 | if (page_nr != last_page_nr) { |
| 1258 | if (p_addr) |
| 1259 | __bm_unmap(p_addr, km); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1260 | if (c < 0) |
| 1261 | bm_set_page_lazy_writeout(b->bm_pages[last_page_nr]); |
| 1262 | else if (c > 0) |
| 1263 | bm_set_page_need_writeout(b->bm_pages[last_page_nr]); |
| 1264 | changed_total += c; |
| 1265 | c = 0; |
| 1266 | p_addr = __bm_map_pidx(b, page_nr, km); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1267 | last_page_nr = page_nr; |
| 1268 | } |
| 1269 | if (val) |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 1270 | c += (0 == generic___test_and_set_le_bit(bitnr & BPP_MASK, p_addr)); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1271 | else |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 1272 | c -= (0 != generic___test_and_clear_le_bit(bitnr & BPP_MASK, p_addr)); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1273 | } |
| 1274 | if (p_addr) |
| 1275 | __bm_unmap(p_addr, km); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1276 | if (c < 0) |
| 1277 | bm_set_page_lazy_writeout(b->bm_pages[last_page_nr]); |
| 1278 | else if (c > 0) |
| 1279 | bm_set_page_need_writeout(b->bm_pages[last_page_nr]); |
| 1280 | changed_total += c; |
| 1281 | b->bm_set += changed_total; |
| 1282 | return changed_total; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1283 | } |
| 1284 | |
| 1285 | /* returns number of bits actually changed. |
| 1286 | * for val != 0, we change 0 -> 1, return code positive |
| 1287 | * for val == 0, we change 1 -> 0, return code negative |
| 1288 | * wants bitnr, not sector */ |
Philipp Reisner | b4ee79d | 2010-04-01 09:57:40 +0200 | [diff] [blame] | 1289 | static int bm_change_bits_to(struct drbd_conf *mdev, const unsigned long s, |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1290 | const unsigned long e, int val) |
| 1291 | { |
| 1292 | unsigned long flags; |
| 1293 | struct drbd_bitmap *b = mdev->bitmap; |
| 1294 | int c = 0; |
| 1295 | |
| 1296 | ERR_IF(!b) return 1; |
| 1297 | ERR_IF(!b->bm_pages) return 0; |
| 1298 | |
| 1299 | spin_lock_irqsave(&b->bm_lock, flags); |
| 1300 | if (bm_is_locked(b)) |
| 1301 | bm_print_lock_info(mdev); |
| 1302 | |
| 1303 | c = __bm_change_bits_to(mdev, s, e, val, KM_IRQ1); |
| 1304 | |
| 1305 | spin_unlock_irqrestore(&b->bm_lock, flags); |
| 1306 | return c; |
| 1307 | } |
| 1308 | |
| 1309 | /* returns number of bits changed 0 -> 1 */ |
| 1310 | int drbd_bm_set_bits(struct drbd_conf *mdev, const unsigned long s, const unsigned long e) |
| 1311 | { |
| 1312 | return bm_change_bits_to(mdev, s, e, 1); |
| 1313 | } |
| 1314 | |
| 1315 | /* returns number of bits changed 1 -> 0 */ |
| 1316 | int drbd_bm_clear_bits(struct drbd_conf *mdev, const unsigned long s, const unsigned long e) |
| 1317 | { |
| 1318 | return -bm_change_bits_to(mdev, s, e, 0); |
| 1319 | } |
| 1320 | |
| 1321 | /* sets all bits in full words, |
| 1322 | * from first_word up to, but not including, last_word */ |
| 1323 | static inline void bm_set_full_words_within_one_page(struct drbd_bitmap *b, |
| 1324 | int page_nr, int first_word, int last_word) |
| 1325 | { |
| 1326 | int i; |
| 1327 | int bits; |
| 1328 | unsigned long *paddr = kmap_atomic(b->bm_pages[page_nr], KM_USER0); |
| 1329 | for (i = first_word; i < last_word; i++) { |
| 1330 | bits = hweight_long(paddr[i]); |
| 1331 | paddr[i] = ~0UL; |
| 1332 | b->bm_set += BITS_PER_LONG - bits; |
| 1333 | } |
| 1334 | kunmap_atomic(paddr, KM_USER0); |
| 1335 | } |
| 1336 | |
| 1337 | /* Same thing as drbd_bm_set_bits, but without taking the spin_lock_irqsave. |
| 1338 | * You must first drbd_bm_lock(). |
| 1339 | * Can be called to set the whole bitmap in one go. |
| 1340 | * Sets bits from s to e _inclusive_. */ |
| 1341 | void _drbd_bm_set_bits(struct drbd_conf *mdev, const unsigned long s, const unsigned long e) |
| 1342 | { |
| 1343 | /* First set_bit from the first bit (s) |
| 1344 | * up to the next long boundary (sl), |
| 1345 | * then assign full words up to the last long boundary (el), |
| 1346 | * then set_bit up to and including the last bit (e). |
| 1347 | * |
| 1348 | * Do not use memset, because we must account for changes, |
| 1349 | * so we need to loop over the words with hweight() anyways. |
| 1350 | */ |
| 1351 | unsigned long sl = ALIGN(s,BITS_PER_LONG); |
| 1352 | unsigned long el = (e+1) & ~((unsigned long)BITS_PER_LONG-1); |
| 1353 | int first_page; |
| 1354 | int last_page; |
| 1355 | int page_nr; |
| 1356 | int first_word; |
| 1357 | int last_word; |
| 1358 | |
| 1359 | if (e - s <= 3*BITS_PER_LONG) { |
| 1360 | /* don't bother; el and sl may even be wrong. */ |
| 1361 | __bm_change_bits_to(mdev, s, e, 1, KM_USER0); |
| 1362 | return; |
| 1363 | } |
| 1364 | |
| 1365 | /* difference is large enough that we can trust sl and el */ |
| 1366 | |
| 1367 | /* bits filling the current long */ |
| 1368 | if (sl) |
| 1369 | __bm_change_bits_to(mdev, s, sl-1, 1, KM_USER0); |
| 1370 | |
| 1371 | first_page = sl >> (3 + PAGE_SHIFT); |
| 1372 | last_page = el >> (3 + PAGE_SHIFT); |
| 1373 | |
| 1374 | /* MLPP: modulo longs per page */ |
| 1375 | /* LWPP: long words per page */ |
| 1376 | first_word = MLPP(sl >> LN2_BPL); |
| 1377 | last_word = LWPP; |
| 1378 | |
| 1379 | /* first and full pages, unless first page == last page */ |
| 1380 | for (page_nr = first_page; page_nr < last_page; page_nr++) { |
| 1381 | bm_set_full_words_within_one_page(mdev->bitmap, page_nr, first_word, last_word); |
| 1382 | cond_resched(); |
| 1383 | first_word = 0; |
| 1384 | } |
| 1385 | |
| 1386 | /* last page (respectively only page, for first page == last page) */ |
| 1387 | last_word = MLPP(el >> LN2_BPL); |
| 1388 | bm_set_full_words_within_one_page(mdev->bitmap, last_page, first_word, last_word); |
| 1389 | |
| 1390 | /* possibly trailing bits. |
| 1391 | * example: (e & 63) == 63, el will be e+1. |
| 1392 | * if that even was the very last bit, |
| 1393 | * it would trigger an assert in __bm_change_bits_to() |
| 1394 | */ |
| 1395 | if (el <= e) |
| 1396 | __bm_change_bits_to(mdev, el, e, 1, KM_USER0); |
| 1397 | } |
| 1398 | |
| 1399 | /* returns bit state |
| 1400 | * wants bitnr, NOT sector. |
| 1401 | * inherently racy... area needs to be locked by means of {al,rs}_lru |
| 1402 | * 1 ... bit set |
| 1403 | * 0 ... bit not set |
| 1404 | * -1 ... first out of bounds access, stop testing for bits! |
| 1405 | */ |
| 1406 | int drbd_bm_test_bit(struct drbd_conf *mdev, const unsigned long bitnr) |
| 1407 | { |
| 1408 | unsigned long flags; |
| 1409 | struct drbd_bitmap *b = mdev->bitmap; |
| 1410 | unsigned long *p_addr; |
| 1411 | int i; |
| 1412 | |
| 1413 | ERR_IF(!b) return 0; |
| 1414 | ERR_IF(!b->bm_pages) return 0; |
| 1415 | |
| 1416 | spin_lock_irqsave(&b->bm_lock, flags); |
| 1417 | if (bm_is_locked(b)) |
| 1418 | bm_print_lock_info(mdev); |
| 1419 | if (bitnr < b->bm_bits) { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1420 | p_addr = bm_map_pidx(b, bm_bit_to_page_idx(b, bitnr)); |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 1421 | i = generic_test_le_bit(bitnr & BPP_MASK, p_addr) ? 1 : 0; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1422 | bm_unmap(p_addr); |
| 1423 | } else if (bitnr == b->bm_bits) { |
| 1424 | i = -1; |
| 1425 | } else { /* (bitnr > b->bm_bits) */ |
| 1426 | dev_err(DEV, "bitnr=%lu > bm_bits=%lu\n", bitnr, b->bm_bits); |
| 1427 | i = 0; |
| 1428 | } |
| 1429 | |
| 1430 | spin_unlock_irqrestore(&b->bm_lock, flags); |
| 1431 | return i; |
| 1432 | } |
| 1433 | |
| 1434 | /* returns number of bits set in the range [s, e] */ |
| 1435 | int drbd_bm_count_bits(struct drbd_conf *mdev, const unsigned long s, const unsigned long e) |
| 1436 | { |
| 1437 | unsigned long flags; |
| 1438 | struct drbd_bitmap *b = mdev->bitmap; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1439 | unsigned long *p_addr = NULL; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1440 | unsigned long bitnr; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1441 | unsigned int page_nr = -1U; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1442 | int c = 0; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1443 | |
| 1444 | /* If this is called without a bitmap, that is a bug. But just to be |
| 1445 | * robust in case we screwed up elsewhere, in that case pretend there |
| 1446 | * was one dirty bit in the requested area, so we won't try to do a |
| 1447 | * local read there (no bitmap probably implies no disk) */ |
| 1448 | ERR_IF(!b) return 1; |
| 1449 | ERR_IF(!b->bm_pages) return 1; |
| 1450 | |
| 1451 | spin_lock_irqsave(&b->bm_lock, flags); |
| 1452 | if (bm_is_locked(b)) |
| 1453 | bm_print_lock_info(mdev); |
| 1454 | for (bitnr = s; bitnr <= e; bitnr++) { |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1455 | unsigned int idx = bm_bit_to_page_idx(b, bitnr); |
| 1456 | if (page_nr != idx) { |
| 1457 | page_nr = idx; |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1458 | if (p_addr) |
| 1459 | bm_unmap(p_addr); |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1460 | p_addr = bm_map_pidx(b, idx); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1461 | } |
| 1462 | ERR_IF (bitnr >= b->bm_bits) { |
| 1463 | dev_err(DEV, "bitnr=%lu bm_bits=%lu\n", bitnr, b->bm_bits); |
| 1464 | } else { |
Lars Ellenberg | 95a0f10 | 2010-12-15 08:59:09 +0100 | [diff] [blame] | 1465 | c += (0 != generic_test_le_bit(bitnr - (page_nr << (PAGE_SHIFT+3)), p_addr)); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1466 | } |
| 1467 | } |
| 1468 | if (p_addr) |
| 1469 | bm_unmap(p_addr); |
| 1470 | spin_unlock_irqrestore(&b->bm_lock, flags); |
| 1471 | return c; |
| 1472 | } |
| 1473 | |
| 1474 | |
| 1475 | /* inherently racy... |
| 1476 | * return value may be already out-of-date when this function returns. |
| 1477 | * but the general usage is that this is only use during a cstate when bits are |
| 1478 | * only cleared, not set, and typically only care for the case when the return |
| 1479 | * value is zero, or we already "locked" this "bitmap extent" by other means. |
| 1480 | * |
| 1481 | * enr is bm-extent number, since we chose to name one sector (512 bytes) |
| 1482 | * worth of the bitmap a "bitmap extent". |
| 1483 | * |
| 1484 | * TODO |
| 1485 | * I think since we use it like a reference count, we should use the real |
| 1486 | * reference count of some bitmap extent element from some lru instead... |
| 1487 | * |
| 1488 | */ |
| 1489 | int drbd_bm_e_weight(struct drbd_conf *mdev, unsigned long enr) |
| 1490 | { |
| 1491 | struct drbd_bitmap *b = mdev->bitmap; |
| 1492 | int count, s, e; |
| 1493 | unsigned long flags; |
| 1494 | unsigned long *p_addr, *bm; |
| 1495 | |
| 1496 | ERR_IF(!b) return 0; |
| 1497 | ERR_IF(!b->bm_pages) return 0; |
| 1498 | |
| 1499 | spin_lock_irqsave(&b->bm_lock, flags); |
| 1500 | if (bm_is_locked(b)) |
| 1501 | bm_print_lock_info(mdev); |
| 1502 | |
| 1503 | s = S2W(enr); |
| 1504 | e = min((size_t)S2W(enr+1), b->bm_words); |
| 1505 | count = 0; |
| 1506 | if (s < b->bm_words) { |
| 1507 | int n = e-s; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1508 | p_addr = bm_map_pidx(b, bm_word_to_page_idx(b, s)); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1509 | bm = p_addr + MLPP(s); |
| 1510 | while (n--) |
| 1511 | count += hweight_long(*bm++); |
| 1512 | bm_unmap(p_addr); |
| 1513 | } else { |
| 1514 | dev_err(DEV, "start offset (%d) too large in drbd_bm_e_weight\n", s); |
| 1515 | } |
| 1516 | spin_unlock_irqrestore(&b->bm_lock, flags); |
| 1517 | return count; |
| 1518 | } |
| 1519 | |
| 1520 | /* set all bits covered by the AL-extent al_enr */ |
| 1521 | unsigned long drbd_bm_ALe_set_all(struct drbd_conf *mdev, unsigned long al_enr) |
| 1522 | { |
| 1523 | struct drbd_bitmap *b = mdev->bitmap; |
| 1524 | unsigned long *p_addr, *bm; |
| 1525 | unsigned long weight; |
| 1526 | int count, s, e, i, do_now; |
| 1527 | ERR_IF(!b) return 0; |
| 1528 | ERR_IF(!b->bm_pages) return 0; |
| 1529 | |
| 1530 | spin_lock_irq(&b->bm_lock); |
| 1531 | if (bm_is_locked(b)) |
| 1532 | bm_print_lock_info(mdev); |
| 1533 | weight = b->bm_set; |
| 1534 | |
| 1535 | s = al_enr * BM_WORDS_PER_AL_EXT; |
| 1536 | e = min_t(size_t, s + BM_WORDS_PER_AL_EXT, b->bm_words); |
| 1537 | /* assert that s and e are on the same page */ |
| 1538 | D_ASSERT((e-1) >> (PAGE_SHIFT - LN2_BPL + 3) |
| 1539 | == s >> (PAGE_SHIFT - LN2_BPL + 3)); |
| 1540 | count = 0; |
| 1541 | if (s < b->bm_words) { |
| 1542 | i = do_now = e-s; |
Lars Ellenberg | 19f843a | 2010-12-15 08:59:11 +0100 | [diff] [blame^] | 1543 | p_addr = bm_map_pidx(b, bm_word_to_page_idx(b, s)); |
Philipp Reisner | b411b36 | 2009-09-25 16:07:19 -0700 | [diff] [blame] | 1544 | bm = p_addr + MLPP(s); |
| 1545 | while (i--) { |
| 1546 | count += hweight_long(*bm); |
| 1547 | *bm = -1UL; |
| 1548 | bm++; |
| 1549 | } |
| 1550 | bm_unmap(p_addr); |
| 1551 | b->bm_set += do_now*BITS_PER_LONG - count; |
| 1552 | if (e == b->bm_words) |
| 1553 | b->bm_set -= bm_clear_surplus(b); |
| 1554 | } else { |
| 1555 | dev_err(DEV, "start offset (%d) too large in drbd_bm_ALe_set_all\n", s); |
| 1556 | } |
| 1557 | weight = b->bm_set - weight; |
| 1558 | spin_unlock_irq(&b->bm_lock); |
| 1559 | return weight; |
| 1560 | } |