linux/fs/gfs2/rgrp.c
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   1/*
   2 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3 * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
   4 *
   5 * This copyrighted material is made available to anyone wishing to use,
   6 * modify, copy, or redistribute it subject to the terms and conditions
   7 * of the GNU General Public License version 2.
   8 */
   9
  10#include <linux/slab.h>
  11#include <linux/spinlock.h>
  12#include <linux/completion.h>
  13#include <linux/buffer_head.h>
  14#include <linux/fs.h>
  15#include <linux/gfs2_ondisk.h>
  16#include <linux/prefetch.h>
  17#include <linux/blkdev.h>
  18#include <linux/rbtree.h>
  19
  20#include "gfs2.h"
  21#include "incore.h"
  22#include "glock.h"
  23#include "glops.h"
  24#include "lops.h"
  25#include "meta_io.h"
  26#include "quota.h"
  27#include "rgrp.h"
  28#include "super.h"
  29#include "trans.h"
  30#include "util.h"
  31#include "log.h"
  32#include "inode.h"
  33#include "trace_gfs2.h"
  34
  35#define BFITNOENT ((u32)~0)
  36#define NO_BLOCK ((u64)~0)
  37
  38#if BITS_PER_LONG == 32
  39#define LBITMASK   (0x55555555UL)
  40#define LBITSKIP55 (0x55555555UL)
  41#define LBITSKIP00 (0x00000000UL)
  42#else
  43#define LBITMASK   (0x5555555555555555UL)
  44#define LBITSKIP55 (0x5555555555555555UL)
  45#define LBITSKIP00 (0x0000000000000000UL)
  46#endif
  47
  48/*
  49 * These routines are used by the resource group routines (rgrp.c)
  50 * to keep track of block allocation.  Each block is represented by two
  51 * bits.  So, each byte represents GFS2_NBBY (i.e. 4) blocks.
  52 *
  53 * 0 = Free
  54 * 1 = Used (not metadata)
  55 * 2 = Unlinked (still in use) inode
  56 * 3 = Used (metadata)
  57 */
  58
  59static const char valid_change[16] = {
  60                /* current */
  61        /* n */ 0, 1, 1, 1,
  62        /* e */ 1, 0, 0, 0,
  63        /* w */ 0, 0, 0, 1,
  64                1, 0, 0, 0
  65};
  66
  67static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 minext,
  68                         const struct gfs2_inode *ip, bool nowrap);
  69
  70
  71/**
  72 * gfs2_setbit - Set a bit in the bitmaps
  73 * @rbm: The position of the bit to set
  74 * @do_clone: Also set the clone bitmap, if it exists
  75 * @new_state: the new state of the block
  76 *
  77 */
  78
  79static inline void gfs2_setbit(const struct gfs2_rbm *rbm, bool do_clone,
  80                               unsigned char new_state)
  81{
  82        unsigned char *byte1, *byte2, *end, cur_state;
  83        unsigned int buflen = rbm->bi->bi_len;
  84        const unsigned int bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE;
  85
  86        byte1 = rbm->bi->bi_bh->b_data + rbm->bi->bi_offset + (rbm->offset / GFS2_NBBY);
  87        end = rbm->bi->bi_bh->b_data + rbm->bi->bi_offset + buflen;
  88
  89        BUG_ON(byte1 >= end);
  90
  91        cur_state = (*byte1 >> bit) & GFS2_BIT_MASK;
  92
  93        if (unlikely(!valid_change[new_state * 4 + cur_state])) {
  94                printk(KERN_WARNING "GFS2: buf_blk = 0x%x old_state=%d, "
  95                       "new_state=%d\n", rbm->offset, cur_state, new_state);
  96                printk(KERN_WARNING "GFS2: rgrp=0x%llx bi_start=0x%x\n",
  97                       (unsigned long long)rbm->rgd->rd_addr,
  98                       rbm->bi->bi_start);
  99                printk(KERN_WARNING "GFS2: bi_offset=0x%x bi_len=0x%x\n",
 100                       rbm->bi->bi_offset, rbm->bi->bi_len);
 101                dump_stack();
 102                gfs2_consist_rgrpd(rbm->rgd);
 103                return;
 104        }
 105        *byte1 ^= (cur_state ^ new_state) << bit;
 106
 107        if (do_clone && rbm->bi->bi_clone) {
 108                byte2 = rbm->bi->bi_clone + rbm->bi->bi_offset + (rbm->offset / GFS2_NBBY);
 109                cur_state = (*byte2 >> bit) & GFS2_BIT_MASK;
 110                *byte2 ^= (cur_state ^ new_state) << bit;
 111        }
 112}
 113
 114/**
 115 * gfs2_testbit - test a bit in the bitmaps
 116 * @rbm: The bit to test
 117 *
 118 * Returns: The two bit block state of the requested bit
 119 */
 120
 121static inline u8 gfs2_testbit(const struct gfs2_rbm *rbm)
 122{
 123        const u8 *buffer = rbm->bi->bi_bh->b_data + rbm->bi->bi_offset;
 124        const u8 *byte;
 125        unsigned int bit;
 126
 127        byte = buffer + (rbm->offset / GFS2_NBBY);
 128        bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE;
 129
 130        return (*byte >> bit) & GFS2_BIT_MASK;
 131}
 132
 133/**
 134 * gfs2_bit_search
 135 * @ptr: Pointer to bitmap data
 136 * @mask: Mask to use (normally 0x55555.... but adjusted for search start)
 137 * @state: The state we are searching for
 138 *
 139 * We xor the bitmap data with a patter which is the bitwise opposite
 140 * of what we are looking for, this gives rise to a pattern of ones
 141 * wherever there is a match. Since we have two bits per entry, we
 142 * take this pattern, shift it down by one place and then and it with
 143 * the original. All the even bit positions (0,2,4, etc) then represent
 144 * successful matches, so we mask with 0x55555..... to remove the unwanted
 145 * odd bit positions.
 146 *
 147 * This allows searching of a whole u64 at once (32 blocks) with a
 148 * single test (on 64 bit arches).
 149 */
 150
 151static inline u64 gfs2_bit_search(const __le64 *ptr, u64 mask, u8 state)
 152{
 153        u64 tmp;
 154        static const u64 search[] = {
 155                [0] = 0xffffffffffffffffULL,
 156                [1] = 0xaaaaaaaaaaaaaaaaULL,
 157                [2] = 0x5555555555555555ULL,
 158                [3] = 0x0000000000000000ULL,
 159        };
 160        tmp = le64_to_cpu(*ptr) ^ search[state];
 161        tmp &= (tmp >> 1);
 162        tmp &= mask;
 163        return tmp;
 164}
 165
 166/**
 167 * rs_cmp - multi-block reservation range compare
 168 * @blk: absolute file system block number of the new reservation
 169 * @len: number of blocks in the new reservation
 170 * @rs: existing reservation to compare against
 171 *
 172 * returns: 1 if the block range is beyond the reach of the reservation
 173 *         -1 if the block range is before the start of the reservation
 174 *          0 if the block range overlaps with the reservation
 175 */
 176static inline int rs_cmp(u64 blk, u32 len, struct gfs2_blkreserv *rs)
 177{
 178        u64 startblk = gfs2_rbm_to_block(&rs->rs_rbm);
 179
 180        if (blk >= startblk + rs->rs_free)
 181                return 1;
 182        if (blk + len - 1 < startblk)
 183                return -1;
 184        return 0;
 185}
 186
 187/**
 188 * gfs2_bitfit - Search an rgrp's bitmap buffer to find a bit-pair representing
 189 *       a block in a given allocation state.
 190 * @buf: the buffer that holds the bitmaps
 191 * @len: the length (in bytes) of the buffer
 192 * @goal: start search at this block's bit-pair (within @buffer)
 193 * @state: GFS2_BLKST_XXX the state of the block we're looking for.
 194 *
 195 * Scope of @goal and returned block number is only within this bitmap buffer,
 196 * not entire rgrp or filesystem.  @buffer will be offset from the actual
 197 * beginning of a bitmap block buffer, skipping any header structures, but
 198 * headers are always a multiple of 64 bits long so that the buffer is
 199 * always aligned to a 64 bit boundary.
 200 *
 201 * The size of the buffer is in bytes, but is it assumed that it is
 202 * always ok to read a complete multiple of 64 bits at the end
 203 * of the block in case the end is no aligned to a natural boundary.
 204 *
 205 * Return: the block number (bitmap buffer scope) that was found
 206 */
 207
 208static u32 gfs2_bitfit(const u8 *buf, const unsigned int len,
 209                       u32 goal, u8 state)
 210{
 211        u32 spoint = (goal << 1) & ((8*sizeof(u64)) - 1);
 212        const __le64 *ptr = ((__le64 *)buf) + (goal >> 5);
 213        const __le64 *end = (__le64 *)(buf + ALIGN(len, sizeof(u64)));
 214        u64 tmp;
 215        u64 mask = 0x5555555555555555ULL;
 216        u32 bit;
 217
 218        /* Mask off bits we don't care about at the start of the search */
 219        mask <<= spoint;
 220        tmp = gfs2_bit_search(ptr, mask, state);
 221        ptr++;
 222        while(tmp == 0 && ptr < end) {
 223                tmp = gfs2_bit_search(ptr, 0x5555555555555555ULL, state);
 224                ptr++;
 225        }
 226        /* Mask off any bits which are more than len bytes from the start */
 227        if (ptr == end && (len & (sizeof(u64) - 1)))
 228                tmp &= (((u64)~0) >> (64 - 8*(len & (sizeof(u64) - 1))));
 229        /* Didn't find anything, so return */
 230        if (tmp == 0)
 231                return BFITNOENT;
 232        ptr--;
 233        bit = __ffs64(tmp);
 234        bit /= 2;       /* two bits per entry in the bitmap */
 235        return (((const unsigned char *)ptr - buf) * GFS2_NBBY) + bit;
 236}
 237
 238/**
 239 * gfs2_rbm_from_block - Set the rbm based upon rgd and block number
 240 * @rbm: The rbm with rgd already set correctly
 241 * @block: The block number (filesystem relative)
 242 *
 243 * This sets the bi and offset members of an rbm based on a
 244 * resource group and a filesystem relative block number. The
 245 * resource group must be set in the rbm on entry, the bi and
 246 * offset members will be set by this function.
 247 *
 248 * Returns: 0 on success, or an error code
 249 */
 250
 251static int gfs2_rbm_from_block(struct gfs2_rbm *rbm, u64 block)
 252{
 253        u64 rblock = block - rbm->rgd->rd_data0;
 254        u32 goal = (u32)rblock;
 255        int x;
 256
 257        if (WARN_ON_ONCE(rblock > UINT_MAX))
 258                return -EINVAL;
 259        if (block >= rbm->rgd->rd_data0 + rbm->rgd->rd_data)
 260                return -E2BIG;
 261
 262        for (x = 0; x < rbm->rgd->rd_length; x++) {
 263                rbm->bi = rbm->rgd->rd_bits + x;
 264                if (goal < (rbm->bi->bi_start + rbm->bi->bi_len) * GFS2_NBBY) {
 265                        rbm->offset = goal - (rbm->bi->bi_start * GFS2_NBBY);
 266                        break;
 267                }
 268        }
 269
 270        return 0;
 271}
 272
 273/**
 274 * gfs2_unaligned_extlen - Look for free blocks which are not byte aligned
 275 * @rbm: Position to search (value/result)
 276 * @n_unaligned: Number of unaligned blocks to check
 277 * @len: Decremented for each block found (terminate on zero)
 278 *
 279 * Returns: true if a non-free block is encountered
 280 */
 281
 282static bool gfs2_unaligned_extlen(struct gfs2_rbm *rbm, u32 n_unaligned, u32 *len)
 283{
 284        u64 block;
 285        u32 n;
 286        u8 res;
 287
 288        for (n = 0; n < n_unaligned; n++) {
 289                res = gfs2_testbit(rbm);
 290                if (res != GFS2_BLKST_FREE)
 291                        return true;
 292                (*len)--;
 293                if (*len == 0)
 294                        return true;
 295                block = gfs2_rbm_to_block(rbm);
 296                if (gfs2_rbm_from_block(rbm, block + 1))
 297                        return true;
 298        }
 299
 300        return false;
 301}
 302
 303/**
 304 * gfs2_free_extlen - Return extent length of free blocks
 305 * @rbm: Starting position
 306 * @len: Max length to check
 307 *
 308 * Starting at the block specified by the rbm, see how many free blocks
 309 * there are, not reading more than len blocks ahead. This can be done
 310 * using memchr_inv when the blocks are byte aligned, but has to be done
 311 * on a block by block basis in case of unaligned blocks. Also this
 312 * function can cope with bitmap boundaries (although it must stop on
 313 * a resource group boundary)
 314 *
 315 * Returns: Number of free blocks in the extent
 316 */
 317
 318static u32 gfs2_free_extlen(const struct gfs2_rbm *rrbm, u32 len)
 319{
 320        struct gfs2_rbm rbm = *rrbm;
 321        u32 n_unaligned = rbm.offset & 3;
 322        u32 size = len;
 323        u32 bytes;
 324        u32 chunk_size;
 325        u8 *ptr, *start, *end;
 326        u64 block;
 327
 328        if (n_unaligned &&
 329            gfs2_unaligned_extlen(&rbm, 4 - n_unaligned, &len))
 330                goto out;
 331
 332        n_unaligned = len & 3;
 333        /* Start is now byte aligned */
 334        while (len > 3) {
 335                start = rbm.bi->bi_bh->b_data;
 336                if (rbm.bi->bi_clone)
 337                        start = rbm.bi->bi_clone;
 338                end = start + rbm.bi->bi_bh->b_size;
 339                start += rbm.bi->bi_offset;
 340                BUG_ON(rbm.offset & 3);
 341                start += (rbm.offset / GFS2_NBBY);
 342                bytes = min_t(u32, len / GFS2_NBBY, (end - start));
 343                ptr = memchr_inv(start, 0, bytes);
 344                chunk_size = ((ptr == NULL) ? bytes : (ptr - start));
 345                chunk_size *= GFS2_NBBY;
 346                BUG_ON(len < chunk_size);
 347                len -= chunk_size;
 348                block = gfs2_rbm_to_block(&rbm);
 349                gfs2_rbm_from_block(&rbm, block + chunk_size);
 350                n_unaligned = 3;
 351                if (ptr)
 352                        break;
 353                n_unaligned = len & 3;
 354        }
 355
 356        /* Deal with any bits left over at the end */
 357        if (n_unaligned)
 358                gfs2_unaligned_extlen(&rbm, n_unaligned, &len);
 359out:
 360        return size - len;
 361}
 362
 363/**
 364 * gfs2_bitcount - count the number of bits in a certain state
 365 * @rgd: the resource group descriptor
 366 * @buffer: the buffer that holds the bitmaps
 367 * @buflen: the length (in bytes) of the buffer
 368 * @state: the state of the block we're looking for
 369 *
 370 * Returns: The number of bits
 371 */
 372
 373static u32 gfs2_bitcount(struct gfs2_rgrpd *rgd, const u8 *buffer,
 374                         unsigned int buflen, u8 state)
 375{
 376        const u8 *byte = buffer;
 377        const u8 *end = buffer + buflen;
 378        const u8 state1 = state << 2;
 379        const u8 state2 = state << 4;
 380        const u8 state3 = state << 6;
 381        u32 count = 0;
 382
 383        for (; byte < end; byte++) {
 384                if (((*byte) & 0x03) == state)
 385                        count++;
 386                if (((*byte) & 0x0C) == state1)
 387                        count++;
 388                if (((*byte) & 0x30) == state2)
 389                        count++;
 390                if (((*byte) & 0xC0) == state3)
 391                        count++;
 392        }
 393
 394        return count;
 395}
 396
 397/**
 398 * gfs2_rgrp_verify - Verify that a resource group is consistent
 399 * @rgd: the rgrp
 400 *
 401 */
 402
 403void gfs2_rgrp_verify(struct gfs2_rgrpd *rgd)
 404{
 405        struct gfs2_sbd *sdp = rgd->rd_sbd;
 406        struct gfs2_bitmap *bi = NULL;
 407        u32 length = rgd->rd_length;
 408        u32 count[4], tmp;
 409        int buf, x;
 410
 411        memset(count, 0, 4 * sizeof(u32));
 412
 413        /* Count # blocks in each of 4 possible allocation states */
 414        for (buf = 0; buf < length; buf++) {
 415                bi = rgd->rd_bits + buf;
 416                for (x = 0; x < 4; x++)
 417                        count[x] += gfs2_bitcount(rgd,
 418                                                  bi->bi_bh->b_data +
 419                                                  bi->bi_offset,
 420                                                  bi->bi_len, x);
 421        }
 422
 423        if (count[0] != rgd->rd_free) {
 424                if (gfs2_consist_rgrpd(rgd))
 425                        fs_err(sdp, "free data mismatch:  %u != %u\n",
 426                               count[0], rgd->rd_free);
 427                return;
 428        }
 429
 430        tmp = rgd->rd_data - rgd->rd_free - rgd->rd_dinodes;
 431        if (count[1] != tmp) {
 432                if (gfs2_consist_rgrpd(rgd))
 433                        fs_err(sdp, "used data mismatch:  %u != %u\n",
 434                               count[1], tmp);
 435                return;
 436        }
 437
 438        if (count[2] + count[3] != rgd->rd_dinodes) {
 439                if (gfs2_consist_rgrpd(rgd))
 440                        fs_err(sdp, "used metadata mismatch:  %u != %u\n",
 441                               count[2] + count[3], rgd->rd_dinodes);
 442                return;
 443        }
 444}
 445
 446static inline int rgrp_contains_block(struct gfs2_rgrpd *rgd, u64 block)
 447{
 448        u64 first = rgd->rd_data0;
 449        u64 last = first + rgd->rd_data;
 450        return first <= block && block < last;
 451}
 452
 453/**
 454 * gfs2_blk2rgrpd - Find resource group for a given data/meta block number
 455 * @sdp: The GFS2 superblock
 456 * @blk: The data block number
 457 * @exact: True if this needs to be an exact match
 458 *
 459 * Returns: The resource group, or NULL if not found
 460 */
 461
 462struct gfs2_rgrpd *gfs2_blk2rgrpd(struct gfs2_sbd *sdp, u64 blk, bool exact)
 463{
 464        struct rb_node *n, *next;
 465        struct gfs2_rgrpd *cur;
 466
 467        spin_lock(&sdp->sd_rindex_spin);
 468        n = sdp->sd_rindex_tree.rb_node;
 469        while (n) {
 470                cur = rb_entry(n, struct gfs2_rgrpd, rd_node);
 471                next = NULL;
 472                if (blk < cur->rd_addr)
 473                        next = n->rb_left;
 474                else if (blk >= cur->rd_data0 + cur->rd_data)
 475                        next = n->rb_right;
 476                if (next == NULL) {
 477                        spin_unlock(&sdp->sd_rindex_spin);
 478                        if (exact) {
 479                                if (blk < cur->rd_addr)
 480                                        return NULL;
 481                                if (blk >= cur->rd_data0 + cur->rd_data)
 482                                        return NULL;
 483                        }
 484                        return cur;
 485                }
 486                n = next;
 487        }
 488        spin_unlock(&sdp->sd_rindex_spin);
 489
 490        return NULL;
 491}
 492
 493/**
 494 * gfs2_rgrpd_get_first - get the first Resource Group in the filesystem
 495 * @sdp: The GFS2 superblock
 496 *
 497 * Returns: The first rgrp in the filesystem
 498 */
 499
 500struct gfs2_rgrpd *gfs2_rgrpd_get_first(struct gfs2_sbd *sdp)
 501{
 502        const struct rb_node *n;
 503        struct gfs2_rgrpd *rgd;
 504
 505        spin_lock(&sdp->sd_rindex_spin);
 506        n = rb_first(&sdp->sd_rindex_tree);
 507        rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 508        spin_unlock(&sdp->sd_rindex_spin);
 509
 510        return rgd;
 511}
 512
 513/**
 514 * gfs2_rgrpd_get_next - get the next RG
 515 * @rgd: the resource group descriptor
 516 *
 517 * Returns: The next rgrp
 518 */
 519
 520struct gfs2_rgrpd *gfs2_rgrpd_get_next(struct gfs2_rgrpd *rgd)
 521{
 522        struct gfs2_sbd *sdp = rgd->rd_sbd;
 523        const struct rb_node *n;
 524
 525        spin_lock(&sdp->sd_rindex_spin);
 526        n = rb_next(&rgd->rd_node);
 527        if (n == NULL)
 528                n = rb_first(&sdp->sd_rindex_tree);
 529
 530        if (unlikely(&rgd->rd_node == n)) {
 531                spin_unlock(&sdp->sd_rindex_spin);
 532                return NULL;
 533        }
 534        rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 535        spin_unlock(&sdp->sd_rindex_spin);
 536        return rgd;
 537}
 538
 539void gfs2_free_clones(struct gfs2_rgrpd *rgd)
 540{
 541        int x;
 542
 543        for (x = 0; x < rgd->rd_length; x++) {
 544                struct gfs2_bitmap *bi = rgd->rd_bits + x;
 545                kfree(bi->bi_clone);
 546                bi->bi_clone = NULL;
 547        }
 548}
 549
 550/**
 551 * gfs2_rs_alloc - make sure we have a reservation assigned to the inode
 552 * @ip: the inode for this reservation
 553 */
 554int gfs2_rs_alloc(struct gfs2_inode *ip)
 555{
 556        struct gfs2_blkreserv *res;
 557
 558        if (ip->i_res)
 559                return 0;
 560
 561        res = kmem_cache_zalloc(gfs2_rsrv_cachep, GFP_NOFS);
 562        if (!res)
 563                return -ENOMEM;
 564
 565        RB_CLEAR_NODE(&res->rs_node);
 566
 567        down_write(&ip->i_rw_mutex);
 568        if (ip->i_res)
 569                kmem_cache_free(gfs2_rsrv_cachep, res);
 570        else
 571                ip->i_res = res;
 572        up_write(&ip->i_rw_mutex);
 573        return 0;
 574}
 575
 576static void dump_rs(struct seq_file *seq, const struct gfs2_blkreserv *rs)
 577{
 578        gfs2_print_dbg(seq, "  B: n:%llu s:%llu b:%u f:%u\n",
 579                       (unsigned long long)rs->rs_inum,
 580                       (unsigned long long)gfs2_rbm_to_block(&rs->rs_rbm),
 581                       rs->rs_rbm.offset, rs->rs_free);
 582}
 583
 584/**
 585 * __rs_deltree - remove a multi-block reservation from the rgd tree
 586 * @rs: The reservation to remove
 587 *
 588 */
 589static void __rs_deltree(struct gfs2_inode *ip, struct gfs2_blkreserv *rs)
 590{
 591        struct gfs2_rgrpd *rgd;
 592
 593        if (!gfs2_rs_active(rs))
 594                return;
 595
 596        rgd = rs->rs_rbm.rgd;
 597        trace_gfs2_rs(rs, TRACE_RS_TREEDEL);
 598        rb_erase(&rs->rs_node, &rgd->rd_rstree);
 599        RB_CLEAR_NODE(&rs->rs_node);
 600
 601        if (rs->rs_free) {
 602                /* return reserved blocks to the rgrp and the ip */
 603                BUG_ON(rs->rs_rbm.rgd->rd_reserved < rs->rs_free);
 604                rs->rs_rbm.rgd->rd_reserved -= rs->rs_free;
 605                rs->rs_free = 0;
 606                clear_bit(GBF_FULL, &rs->rs_rbm.bi->bi_flags);
 607                smp_mb__after_clear_bit();
 608        }
 609}
 610
 611/**
 612 * gfs2_rs_deltree - remove a multi-block reservation from the rgd tree
 613 * @rs: The reservation to remove
 614 *
 615 */
 616void gfs2_rs_deltree(struct gfs2_inode *ip, struct gfs2_blkreserv *rs)
 617{
 618        struct gfs2_rgrpd *rgd;
 619
 620        rgd = rs->rs_rbm.rgd;
 621        if (rgd) {
 622                spin_lock(&rgd->rd_rsspin);
 623                __rs_deltree(ip, rs);
 624                spin_unlock(&rgd->rd_rsspin);
 625        }
 626}
 627
 628/**
 629 * gfs2_rs_delete - delete a multi-block reservation
 630 * @ip: The inode for this reservation
 631 *
 632 */
 633void gfs2_rs_delete(struct gfs2_inode *ip)
 634{
 635        down_write(&ip->i_rw_mutex);
 636        if (ip->i_res) {
 637                gfs2_rs_deltree(ip, ip->i_res);
 638                BUG_ON(ip->i_res->rs_free);
 639                kmem_cache_free(gfs2_rsrv_cachep, ip->i_res);
 640                ip->i_res = NULL;
 641        }
 642        up_write(&ip->i_rw_mutex);
 643}
 644
 645/**
 646 * return_all_reservations - return all reserved blocks back to the rgrp.
 647 * @rgd: the rgrp that needs its space back
 648 *
 649 * We previously reserved a bunch of blocks for allocation. Now we need to
 650 * give them back. This leave the reservation structures in tact, but removes
 651 * all of their corresponding "no-fly zones".
 652 */
 653static void return_all_reservations(struct gfs2_rgrpd *rgd)
 654{
 655        struct rb_node *n;
 656        struct gfs2_blkreserv *rs;
 657
 658        spin_lock(&rgd->rd_rsspin);
 659        while ((n = rb_first(&rgd->rd_rstree))) {
 660                rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
 661                __rs_deltree(NULL, rs);
 662        }
 663        spin_unlock(&rgd->rd_rsspin);
 664}
 665
 666void gfs2_clear_rgrpd(struct gfs2_sbd *sdp)
 667{
 668        struct rb_node *n;
 669        struct gfs2_rgrpd *rgd;
 670        struct gfs2_glock *gl;
 671
 672        while ((n = rb_first(&sdp->sd_rindex_tree))) {
 673                rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 674                gl = rgd->rd_gl;
 675
 676                rb_erase(n, &sdp->sd_rindex_tree);
 677
 678                if (gl) {
 679                        spin_lock(&gl->gl_spin);
 680                        gl->gl_object = NULL;
 681                        spin_unlock(&gl->gl_spin);
 682                        gfs2_glock_add_to_lru(gl);
 683                        gfs2_glock_put(gl);
 684                }
 685
 686                gfs2_free_clones(rgd);
 687                kfree(rgd->rd_bits);
 688                return_all_reservations(rgd);
 689                kmem_cache_free(gfs2_rgrpd_cachep, rgd);
 690        }
 691}
 692
 693static void gfs2_rindex_print(const struct gfs2_rgrpd *rgd)
 694{
 695        printk(KERN_INFO "  ri_addr = %llu\n", (unsigned long long)rgd->rd_addr);
 696        printk(KERN_INFO "  ri_length = %u\n", rgd->rd_length);
 697        printk(KERN_INFO "  ri_data0 = %llu\n", (unsigned long long)rgd->rd_data0);
 698        printk(KERN_INFO "  ri_data = %u\n", rgd->rd_data);
 699        printk(KERN_INFO "  ri_bitbytes = %u\n", rgd->rd_bitbytes);
 700}
 701
 702/**
 703 * gfs2_compute_bitstructs - Compute the bitmap sizes
 704 * @rgd: The resource group descriptor
 705 *
 706 * Calculates bitmap descriptors, one for each block that contains bitmap data
 707 *
 708 * Returns: errno
 709 */
 710
 711static int compute_bitstructs(struct gfs2_rgrpd *rgd)
 712{
 713        struct gfs2_sbd *sdp = rgd->rd_sbd;
 714        struct gfs2_bitmap *bi;
 715        u32 length = rgd->rd_length; /* # blocks in hdr & bitmap */
 716        u32 bytes_left, bytes;
 717        int x;
 718
 719        if (!length)
 720                return -EINVAL;
 721
 722        rgd->rd_bits = kcalloc(length, sizeof(struct gfs2_bitmap), GFP_NOFS);
 723        if (!rgd->rd_bits)
 724                return -ENOMEM;
 725
 726        bytes_left = rgd->rd_bitbytes;
 727
 728        for (x = 0; x < length; x++) {
 729                bi = rgd->rd_bits + x;
 730
 731                bi->bi_flags = 0;
 732                /* small rgrp; bitmap stored completely in header block */
 733                if (length == 1) {
 734                        bytes = bytes_left;
 735                        bi->bi_offset = sizeof(struct gfs2_rgrp);
 736                        bi->bi_start = 0;
 737                        bi->bi_len = bytes;
 738                /* header block */
 739                } else if (x == 0) {
 740                        bytes = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_rgrp);
 741                        bi->bi_offset = sizeof(struct gfs2_rgrp);
 742                        bi->bi_start = 0;
 743                        bi->bi_len = bytes;
 744                /* last block */
 745                } else if (x + 1 == length) {
 746                        bytes = bytes_left;
 747                        bi->bi_offset = sizeof(struct gfs2_meta_header);
 748                        bi->bi_start = rgd->rd_bitbytes - bytes_left;
 749                        bi->bi_len = bytes;
 750                /* other blocks */
 751                } else {
 752                        bytes = sdp->sd_sb.sb_bsize -
 753                                sizeof(struct gfs2_meta_header);
 754                        bi->bi_offset = sizeof(struct gfs2_meta_header);
 755                        bi->bi_start = rgd->rd_bitbytes - bytes_left;
 756                        bi->bi_len = bytes;
 757                }
 758
 759                bytes_left -= bytes;
 760        }
 761
 762        if (bytes_left) {
 763                gfs2_consist_rgrpd(rgd);
 764                return -EIO;
 765        }
 766        bi = rgd->rd_bits + (length - 1);
 767        if ((bi->bi_start + bi->bi_len) * GFS2_NBBY != rgd->rd_data) {
 768                if (gfs2_consist_rgrpd(rgd)) {
 769                        gfs2_rindex_print(rgd);
 770                        fs_err(sdp, "start=%u len=%u offset=%u\n",
 771                               bi->bi_start, bi->bi_len, bi->bi_offset);
 772                }
 773                return -EIO;
 774        }
 775
 776        return 0;
 777}
 778
 779/**
 780 * gfs2_ri_total - Total up the file system space, according to the rindex.
 781 * @sdp: the filesystem
 782 *
 783 */
 784u64 gfs2_ri_total(struct gfs2_sbd *sdp)
 785{
 786        u64 total_data = 0;     
 787        struct inode *inode = sdp->sd_rindex;
 788        struct gfs2_inode *ip = GFS2_I(inode);
 789        char buf[sizeof(struct gfs2_rindex)];
 790        int error, rgrps;
 791
 792        for (rgrps = 0;; rgrps++) {
 793                loff_t pos = rgrps * sizeof(struct gfs2_rindex);
 794
 795                if (pos + sizeof(struct gfs2_rindex) > i_size_read(inode))
 796                        break;
 797                error = gfs2_internal_read(ip, buf, &pos,
 798                                           sizeof(struct gfs2_rindex));
 799                if (error != sizeof(struct gfs2_rindex))
 800                        break;
 801                total_data += be32_to_cpu(((struct gfs2_rindex *)buf)->ri_data);
 802        }
 803        return total_data;
 804}
 805
 806static int rgd_insert(struct gfs2_rgrpd *rgd)
 807{
 808        struct gfs2_sbd *sdp = rgd->rd_sbd;
 809        struct rb_node **newn = &sdp->sd_rindex_tree.rb_node, *parent = NULL;
 810
 811        /* Figure out where to put new node */
 812        while (*newn) {
 813                struct gfs2_rgrpd *cur = rb_entry(*newn, struct gfs2_rgrpd,
 814                                                  rd_node);
 815
 816                parent = *newn;
 817                if (rgd->rd_addr < cur->rd_addr)
 818                        newn = &((*newn)->rb_left);
 819                else if (rgd->rd_addr > cur->rd_addr)
 820                        newn = &((*newn)->rb_right);
 821                else
 822                        return -EEXIST;
 823        }
 824
 825        rb_link_node(&rgd->rd_node, parent, newn);
 826        rb_insert_color(&rgd->rd_node, &sdp->sd_rindex_tree);
 827        sdp->sd_rgrps++;
 828        return 0;
 829}
 830
 831/**
 832 * read_rindex_entry - Pull in a new resource index entry from the disk
 833 * @ip: Pointer to the rindex inode
 834 *
 835 * Returns: 0 on success, > 0 on EOF, error code otherwise
 836 */
 837
 838static int read_rindex_entry(struct gfs2_inode *ip)
 839{
 840        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 841        loff_t pos = sdp->sd_rgrps * sizeof(struct gfs2_rindex);
 842        struct gfs2_rindex buf;
 843        int error;
 844        struct gfs2_rgrpd *rgd;
 845
 846        if (pos >= i_size_read(&ip->i_inode))
 847                return 1;
 848
 849        error = gfs2_internal_read(ip, (char *)&buf, &pos,
 850                                   sizeof(struct gfs2_rindex));
 851
 852        if (error != sizeof(struct gfs2_rindex))
 853                return (error == 0) ? 1 : error;
 854
 855        rgd = kmem_cache_zalloc(gfs2_rgrpd_cachep, GFP_NOFS);
 856        error = -ENOMEM;
 857        if (!rgd)
 858                return error;
 859
 860        rgd->rd_sbd = sdp;
 861        rgd->rd_addr = be64_to_cpu(buf.ri_addr);
 862        rgd->rd_length = be32_to_cpu(buf.ri_length);
 863        rgd->rd_data0 = be64_to_cpu(buf.ri_data0);
 864        rgd->rd_data = be32_to_cpu(buf.ri_data);
 865        rgd->rd_bitbytes = be32_to_cpu(buf.ri_bitbytes);
 866        spin_lock_init(&rgd->rd_rsspin);
 867
 868        error = compute_bitstructs(rgd);
 869        if (error)
 870                goto fail;
 871
 872        error = gfs2_glock_get(sdp, rgd->rd_addr,
 873                               &gfs2_rgrp_glops, CREATE, &rgd->rd_gl);
 874        if (error)
 875                goto fail;
 876
 877        rgd->rd_gl->gl_object = rgd;
 878        rgd->rd_rgl = (struct gfs2_rgrp_lvb *)rgd->rd_gl->gl_lvb;
 879        rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
 880        if (rgd->rd_data > sdp->sd_max_rg_data)
 881                sdp->sd_max_rg_data = rgd->rd_data;
 882        spin_lock(&sdp->sd_rindex_spin);
 883        error = rgd_insert(rgd);
 884        spin_unlock(&sdp->sd_rindex_spin);
 885        if (!error)
 886                return 0;
 887
 888        error = 0; /* someone else read in the rgrp; free it and ignore it */
 889        gfs2_glock_put(rgd->rd_gl);
 890
 891fail:
 892        kfree(rgd->rd_bits);
 893        kmem_cache_free(gfs2_rgrpd_cachep, rgd);
 894        return error;
 895}
 896
 897/**
 898 * gfs2_ri_update - Pull in a new resource index from the disk
 899 * @ip: pointer to the rindex inode
 900 *
 901 * Returns: 0 on successful update, error code otherwise
 902 */
 903
 904static int gfs2_ri_update(struct gfs2_inode *ip)
 905{
 906        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 907        int error;
 908
 909        do {
 910                error = read_rindex_entry(ip);
 911        } while (error == 0);
 912
 913        if (error < 0)
 914                return error;
 915
 916        sdp->sd_rindex_uptodate = 1;
 917        return 0;
 918}
 919
 920/**
 921 * gfs2_rindex_update - Update the rindex if required
 922 * @sdp: The GFS2 superblock
 923 *
 924 * We grab a lock on the rindex inode to make sure that it doesn't
 925 * change whilst we are performing an operation. We keep this lock
 926 * for quite long periods of time compared to other locks. This
 927 * doesn't matter, since it is shared and it is very, very rarely
 928 * accessed in the exclusive mode (i.e. only when expanding the filesystem).
 929 *
 930 * This makes sure that we're using the latest copy of the resource index
 931 * special file, which might have been updated if someone expanded the
 932 * filesystem (via gfs2_grow utility), which adds new resource groups.
 933 *
 934 * Returns: 0 on succeess, error code otherwise
 935 */
 936
 937int gfs2_rindex_update(struct gfs2_sbd *sdp)
 938{
 939        struct gfs2_inode *ip = GFS2_I(sdp->sd_rindex);
 940        struct gfs2_glock *gl = ip->i_gl;
 941        struct gfs2_holder ri_gh;
 942        int error = 0;
 943        int unlock_required = 0;
 944
 945        /* Read new copy from disk if we don't have the latest */
 946        if (!sdp->sd_rindex_uptodate) {
 947                if (!gfs2_glock_is_locked_by_me(gl)) {
 948                        error = gfs2_glock_nq_init(gl, LM_ST_SHARED, 0, &ri_gh);
 949                        if (error)
 950                                return error;
 951                        unlock_required = 1;
 952                }
 953                if (!sdp->sd_rindex_uptodate)
 954                        error = gfs2_ri_update(ip);
 955                if (unlock_required)
 956                        gfs2_glock_dq_uninit(&ri_gh);
 957        }
 958
 959        return error;
 960}
 961
 962static void gfs2_rgrp_in(struct gfs2_rgrpd *rgd, const void *buf)
 963{
 964        const struct gfs2_rgrp *str = buf;
 965        u32 rg_flags;
 966
 967        rg_flags = be32_to_cpu(str->rg_flags);
 968        rg_flags &= ~GFS2_RDF_MASK;
 969        rgd->rd_flags &= GFS2_RDF_MASK;
 970        rgd->rd_flags |= rg_flags;
 971        rgd->rd_free = be32_to_cpu(str->rg_free);
 972        rgd->rd_dinodes = be32_to_cpu(str->rg_dinodes);
 973        rgd->rd_igeneration = be64_to_cpu(str->rg_igeneration);
 974}
 975
 976static void gfs2_rgrp_out(struct gfs2_rgrpd *rgd, void *buf)
 977{
 978        struct gfs2_rgrp *str = buf;
 979
 980        str->rg_flags = cpu_to_be32(rgd->rd_flags & ~GFS2_RDF_MASK);
 981        str->rg_free = cpu_to_be32(rgd->rd_free);
 982        str->rg_dinodes = cpu_to_be32(rgd->rd_dinodes);
 983        str->__pad = cpu_to_be32(0);
 984        str->rg_igeneration = cpu_to_be64(rgd->rd_igeneration);
 985        memset(&str->rg_reserved, 0, sizeof(str->rg_reserved));
 986}
 987
 988static int gfs2_rgrp_lvb_valid(struct gfs2_rgrpd *rgd)
 989{
 990        struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
 991        struct gfs2_rgrp *str = (struct gfs2_rgrp *)rgd->rd_bits[0].bi_bh->b_data;
 992
 993        if (rgl->rl_flags != str->rg_flags || rgl->rl_free != str->rg_free ||
 994            rgl->rl_dinodes != str->rg_dinodes ||
 995            rgl->rl_igeneration != str->rg_igeneration)
 996                return 0;
 997        return 1;
 998}
 999
1000static void gfs2_rgrp_ondisk2lvb(struct gfs2_rgrp_lvb *rgl, const void *buf)
1001{
1002        const struct gfs2_rgrp *str = buf;
1003
1004        rgl->rl_magic = cpu_to_be32(GFS2_MAGIC);
1005        rgl->rl_flags = str->rg_flags;
1006        rgl->rl_free = str->rg_free;
1007        rgl->rl_dinodes = str->rg_dinodes;
1008        rgl->rl_igeneration = str->rg_igeneration;
1009        rgl->__pad = 0UL;
1010}
1011
1012static void update_rgrp_lvb_unlinked(struct gfs2_rgrpd *rgd, u32 change)
1013{
1014        struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
1015        u32 unlinked = be32_to_cpu(rgl->rl_unlinked) + change;
1016        rgl->rl_unlinked = cpu_to_be32(unlinked);
1017}
1018
1019static u32 count_unlinked(struct gfs2_rgrpd *rgd)
1020{
1021        struct gfs2_bitmap *bi;
1022        const u32 length = rgd->rd_length;
1023        const u8 *buffer = NULL;
1024        u32 i, goal, count = 0;
1025
1026        for (i = 0, bi = rgd->rd_bits; i < length; i++, bi++) {
1027                goal = 0;
1028                buffer = bi->bi_bh->b_data + bi->bi_offset;
1029                WARN_ON(!buffer_uptodate(bi->bi_bh));
1030                while (goal < bi->bi_len * GFS2_NBBY) {
1031                        goal = gfs2_bitfit(buffer, bi->bi_len, goal,
1032                                           GFS2_BLKST_UNLINKED);
1033                        if (goal == BFITNOENT)
1034                                break;
1035                        count++;
1036                        goal++;
1037                }
1038        }
1039
1040        return count;
1041}
1042
1043
1044/**
1045 * gfs2_rgrp_bh_get - Read in a RG's header and bitmaps
1046 * @rgd: the struct gfs2_rgrpd describing the RG to read in
1047 *
1048 * Read in all of a Resource Group's header and bitmap blocks.
1049 * Caller must eventually call gfs2_rgrp_relse() to free the bitmaps.
1050 *
1051 * Returns: errno
1052 */
1053
1054int gfs2_rgrp_bh_get(struct gfs2_rgrpd *rgd)
1055{
1056        struct gfs2_sbd *sdp = rgd->rd_sbd;
1057        struct gfs2_glock *gl = rgd->rd_gl;
1058        unsigned int length = rgd->rd_length;
1059        struct gfs2_bitmap *bi;
1060        unsigned int x, y;
1061        int error;
1062
1063        if (rgd->rd_bits[0].bi_bh != NULL)
1064                return 0;
1065
1066        for (x = 0; x < length; x++) {
1067                bi = rgd->rd_bits + x;
1068                error = gfs2_meta_read(gl, rgd->rd_addr + x, 0, &bi->bi_bh);
1069                if (error)
1070                        goto fail;
1071        }
1072
1073        for (y = length; y--;) {
1074                bi = rgd->rd_bits + y;
1075                error = gfs2_meta_wait(sdp, bi->bi_bh);
1076                if (error)
1077                        goto fail;
1078                if (gfs2_metatype_check(sdp, bi->bi_bh, y ? GFS2_METATYPE_RB :
1079                                              GFS2_METATYPE_RG)) {
1080                        error = -EIO;
1081                        goto fail;
1082                }
1083        }
1084
1085        if (!(rgd->rd_flags & GFS2_RDF_UPTODATE)) {
1086                for (x = 0; x < length; x++)
1087                        clear_bit(GBF_FULL, &rgd->rd_bits[x].bi_flags);
1088                gfs2_rgrp_in(rgd, (rgd->rd_bits[0].bi_bh)->b_data);
1089                rgd->rd_flags |= (GFS2_RDF_UPTODATE | GFS2_RDF_CHECK);
1090                rgd->rd_free_clone = rgd->rd_free;
1091        }
1092        if (be32_to_cpu(GFS2_MAGIC) != rgd->rd_rgl->rl_magic) {
1093                rgd->rd_rgl->rl_unlinked = cpu_to_be32(count_unlinked(rgd));
1094                gfs2_rgrp_ondisk2lvb(rgd->rd_rgl,
1095                                     rgd->rd_bits[0].bi_bh->b_data);
1096        }
1097        else if (sdp->sd_args.ar_rgrplvb) {
1098                if (!gfs2_rgrp_lvb_valid(rgd)){
1099                        gfs2_consist_rgrpd(rgd);
1100                        error = -EIO;
1101                        goto fail;
1102                }
1103                if (rgd->rd_rgl->rl_unlinked == 0)
1104                        rgd->rd_flags &= ~GFS2_RDF_CHECK;
1105        }
1106        return 0;
1107
1108fail:
1109        while (x--) {
1110                bi = rgd->rd_bits + x;
1111                brelse(bi->bi_bh);
1112                bi->bi_bh = NULL;
1113                gfs2_assert_warn(sdp, !bi->bi_clone);
1114        }
1115
1116        return error;
1117}
1118
1119int update_rgrp_lvb(struct gfs2_rgrpd *rgd)
1120{
1121        u32 rl_flags;
1122
1123        if (rgd->rd_flags & GFS2_RDF_UPTODATE)
1124                return 0;
1125
1126        if (be32_to_cpu(GFS2_MAGIC) != rgd->rd_rgl->rl_magic)
1127                return gfs2_rgrp_bh_get(rgd);
1128
1129        rl_flags = be32_to_cpu(rgd->rd_rgl->rl_flags);
1130        rl_flags &= ~GFS2_RDF_MASK;
1131        rgd->rd_flags &= GFS2_RDF_MASK;
1132        rgd->rd_flags |= (rl_flags | GFS2_RDF_UPTODATE | GFS2_RDF_CHECK);
1133        if (rgd->rd_rgl->rl_unlinked == 0)
1134                rgd->rd_flags &= ~GFS2_RDF_CHECK;
1135        rgd->rd_free = be32_to_cpu(rgd->rd_rgl->rl_free);
1136        rgd->rd_free_clone = rgd->rd_free;
1137        rgd->rd_dinodes = be32_to_cpu(rgd->rd_rgl->rl_dinodes);
1138        rgd->rd_igeneration = be64_to_cpu(rgd->rd_rgl->rl_igeneration);
1139        return 0;
1140}
1141
1142int gfs2_rgrp_go_lock(struct gfs2_holder *gh)
1143{
1144        struct gfs2_rgrpd *rgd = gh->gh_gl->gl_object;
1145        struct gfs2_sbd *sdp = rgd->rd_sbd;
1146
1147        if (gh->gh_flags & GL_SKIP && sdp->sd_args.ar_rgrplvb)
1148                return 0;
1149        return gfs2_rgrp_bh_get((struct gfs2_rgrpd *)gh->gh_gl->gl_object);
1150}
1151
1152/**
1153 * gfs2_rgrp_go_unlock - Release RG bitmaps read in with gfs2_rgrp_bh_get()
1154 * @gh: The glock holder for the resource group
1155 *
1156 */
1157
1158void gfs2_rgrp_go_unlock(struct gfs2_holder *gh)
1159{
1160        struct gfs2_rgrpd *rgd = gh->gh_gl->gl_object;
1161        int x, length = rgd->rd_length;
1162
1163        for (x = 0; x < length; x++) {
1164                struct gfs2_bitmap *bi = rgd->rd_bits + x;
1165                if (bi->bi_bh) {
1166                        brelse(bi->bi_bh);
1167                        bi->bi_bh = NULL;
1168                }
1169        }
1170
1171}
1172
1173int gfs2_rgrp_send_discards(struct gfs2_sbd *sdp, u64 offset,
1174                             struct buffer_head *bh,
1175                             const struct gfs2_bitmap *bi, unsigned minlen, u64 *ptrimmed)
1176{
1177        struct super_block *sb = sdp->sd_vfs;
1178        struct block_device *bdev = sb->s_bdev;
1179        const unsigned int sects_per_blk = sdp->sd_sb.sb_bsize /
1180                                           bdev_logical_block_size(sb->s_bdev);
1181        u64 blk;
1182        sector_t start = 0;
1183        sector_t nr_sects = 0;
1184        int rv;
1185        unsigned int x;
1186        u32 trimmed = 0;
1187        u8 diff;
1188
1189        for (x = 0; x < bi->bi_len; x++) {
1190                const u8 *clone = bi->bi_clone ? bi->bi_clone : bi->bi_bh->b_data;
1191                clone += bi->bi_offset;
1192                clone += x;
1193                if (bh) {
1194                        const u8 *orig = bh->b_data + bi->bi_offset + x;
1195                        diff = ~(*orig | (*orig >> 1)) & (*clone | (*clone >> 1));
1196                } else {
1197                        diff = ~(*clone | (*clone >> 1));
1198                }
1199                diff &= 0x55;
1200                if (diff == 0)
1201                        continue;
1202                blk = offset + ((bi->bi_start + x) * GFS2_NBBY);
1203                blk *= sects_per_blk; /* convert to sectors */
1204                while(diff) {
1205                        if (diff & 1) {
1206                                if (nr_sects == 0)
1207                                        goto start_new_extent;
1208                                if ((start + nr_sects) != blk) {
1209                                        if (nr_sects >= minlen) {
1210                                                rv = blkdev_issue_discard(bdev,
1211                                                        start, nr_sects,
1212                                                        GFP_NOFS, 0);
1213                                                if (rv)
1214                                                        goto fail;
1215                                                trimmed += nr_sects;
1216                                        }
1217                                        nr_sects = 0;
1218start_new_extent:
1219                                        start = blk;
1220                                }
1221                                nr_sects += sects_per_blk;
1222                        }
1223                        diff >>= 2;
1224                        blk += sects_per_blk;
1225                }
1226        }
1227        if (nr_sects >= minlen) {
1228                rv = blkdev_issue_discard(bdev, start, nr_sects, GFP_NOFS, 0);
1229                if (rv)
1230                        goto fail;
1231                trimmed += nr_sects;
1232        }
1233        if (ptrimmed)
1234                *ptrimmed = trimmed;
1235        return 0;
1236
1237fail:
1238        if (sdp->sd_args.ar_discard)
1239                fs_warn(sdp, "error %d on discard request, turning discards off for this filesystem", rv);
1240        sdp->sd_args.ar_discard = 0;
1241        return -EIO;
1242}
1243
1244/**
1245 * gfs2_fitrim - Generate discard requests for unused bits of the filesystem
1246 * @filp: Any file on the filesystem
1247 * @argp: Pointer to the arguments (also used to pass result)
1248 *
1249 * Returns: 0 on success, otherwise error code
1250 */
1251
1252int gfs2_fitrim(struct file *filp, void __user *argp)
1253{
1254        struct inode *inode = filp->f_dentry->d_inode;
1255        struct gfs2_sbd *sdp = GFS2_SB(inode);
1256        struct request_queue *q = bdev_get_queue(sdp->sd_vfs->s_bdev);
1257        struct buffer_head *bh;
1258        struct gfs2_rgrpd *rgd;
1259        struct gfs2_rgrpd *rgd_end;
1260        struct gfs2_holder gh;
1261        struct fstrim_range r;
1262        int ret = 0;
1263        u64 amt;
1264        u64 trimmed = 0;
1265        u64 start, end, minlen;
1266        unsigned int x;
1267        unsigned bs_shift = sdp->sd_sb.sb_bsize_shift;
1268
1269        if (!capable(CAP_SYS_ADMIN))
1270                return -EPERM;
1271
1272        if (!blk_queue_discard(q))
1273                return -EOPNOTSUPP;
1274
1275        if (copy_from_user(&r, argp, sizeof(r)))
1276                return -EFAULT;
1277
1278        ret = gfs2_rindex_update(sdp);
1279        if (ret)
1280                return ret;
1281
1282        start = r.start >> bs_shift;
1283        end = start + (r.len >> bs_shift);
1284        minlen = max_t(u64, r.minlen,
1285                       q->limits.discard_granularity) >> bs_shift;
1286
1287        rgd = gfs2_blk2rgrpd(sdp, start, 0);
1288        rgd_end = gfs2_blk2rgrpd(sdp, end - 1, 0);
1289
1290        if (end <= start ||
1291            minlen > sdp->sd_max_rg_data ||
1292            start > rgd_end->rd_data0 + rgd_end->rd_data)
1293                return -EINVAL;
1294
1295        while (1) {
1296
1297                ret = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
1298                if (ret)
1299                        goto out;
1300
1301                if (!(rgd->rd_flags & GFS2_RGF_TRIMMED)) {
1302                        /* Trim each bitmap in the rgrp */
1303                        for (x = 0; x < rgd->rd_length; x++) {
1304                                struct gfs2_bitmap *bi = rgd->rd_bits + x;
1305                                ret = gfs2_rgrp_send_discards(sdp,
1306                                                rgd->rd_data0, NULL, bi, minlen,
1307                                                &amt);
1308                                if (ret) {
1309                                        gfs2_glock_dq_uninit(&gh);
1310                                        goto out;
1311                                }
1312                                trimmed += amt;
1313                        }
1314
1315                        /* Mark rgrp as having been trimmed */
1316                        ret = gfs2_trans_begin(sdp, RES_RG_HDR, 0);
1317                        if (ret == 0) {
1318                                bh = rgd->rd_bits[0].bi_bh;
1319                                rgd->rd_flags |= GFS2_RGF_TRIMMED;
1320                                gfs2_trans_add_bh(rgd->rd_gl, bh, 1);
1321                                gfs2_rgrp_out(rgd, bh->b_data);
1322                                gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, bh->b_data);
1323                                gfs2_trans_end(sdp);
1324                        }
1325                }
1326                gfs2_glock_dq_uninit(&gh);
1327
1328                if (rgd == rgd_end)
1329                        break;
1330
1331                rgd = gfs2_rgrpd_get_next(rgd);
1332        }
1333
1334out:
1335        r.len = trimmed << 9;
1336        if (copy_to_user(argp, &r, sizeof(r)))
1337                return -EFAULT;
1338
1339        return ret;
1340}
1341
1342/**
1343 * rs_insert - insert a new multi-block reservation into the rgrp's rb_tree
1344 * @ip: the inode structure
1345 *
1346 */
1347static void rs_insert(struct gfs2_inode *ip)
1348{
1349        struct rb_node **newn, *parent = NULL;
1350        int rc;
1351        struct gfs2_blkreserv *rs = ip->i_res;
1352        struct gfs2_rgrpd *rgd = rs->rs_rbm.rgd;
1353        u64 fsblock = gfs2_rbm_to_block(&rs->rs_rbm);
1354
1355        BUG_ON(gfs2_rs_active(rs));
1356
1357        spin_lock(&rgd->rd_rsspin);
1358        newn = &rgd->rd_rstree.rb_node;
1359        while (*newn) {
1360                struct gfs2_blkreserv *cur =
1361                        rb_entry(*newn, struct gfs2_blkreserv, rs_node);
1362
1363                parent = *newn;
1364                rc = rs_cmp(fsblock, rs->rs_free, cur);
1365                if (rc > 0)
1366                        newn = &((*newn)->rb_right);
1367                else if (rc < 0)
1368                        newn = &((*newn)->rb_left);
1369                else {
1370                        spin_unlock(&rgd->rd_rsspin);
1371                        WARN_ON(1);
1372                        return;
1373                }
1374        }
1375
1376        rb_link_node(&rs->rs_node, parent, newn);
1377        rb_insert_color(&rs->rs_node, &rgd->rd_rstree);
1378
1379        /* Do our rgrp accounting for the reservation */
1380        rgd->rd_reserved += rs->rs_free; /* blocks reserved */
1381        spin_unlock(&rgd->rd_rsspin);
1382        trace_gfs2_rs(rs, TRACE_RS_INSERT);
1383}
1384
1385/**
1386 * rg_mblk_search - find a group of multiple free blocks to form a reservation
1387 * @rgd: the resource group descriptor
1388 * @ip: pointer to the inode for which we're reserving blocks
1389 * @requested: number of blocks required for this allocation
1390 *
1391 */
1392
1393static void rg_mblk_search(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip,
1394                           unsigned requested)
1395{
1396        struct gfs2_rbm rbm = { .rgd = rgd, };
1397        u64 goal;
1398        struct gfs2_blkreserv *rs = ip->i_res;
1399        u32 extlen;
1400        u32 free_blocks = rgd->rd_free_clone - rgd->rd_reserved;
1401        int ret;
1402
1403        extlen = max_t(u32, atomic_read(&rs->rs_sizehint), requested);
1404        extlen = clamp(extlen, RGRP_RSRV_MINBLKS, free_blocks);
1405        if ((rgd->rd_free_clone < rgd->rd_reserved) || (free_blocks < extlen))
1406                return;
1407
1408        /* Find bitmap block that contains bits for goal block */
1409        if (rgrp_contains_block(rgd, ip->i_goal))
1410                goal = ip->i_goal;
1411        else
1412                goal = rgd->rd_last_alloc + rgd->rd_data0;
1413
1414        if (WARN_ON(gfs2_rbm_from_block(&rbm, goal)))
1415                return;
1416
1417        ret = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, extlen, ip, true);
1418        if (ret == 0) {
1419                rs->rs_rbm = rbm;
1420                rs->rs_free = extlen;
1421                rs->rs_inum = ip->i_no_addr;
1422                rs_insert(ip);
1423        }
1424}
1425
1426/**
1427 * gfs2_next_unreserved_block - Return next block that is not reserved
1428 * @rgd: The resource group
1429 * @block: The starting block
1430 * @length: The required length
1431 * @ip: Ignore any reservations for this inode
1432 *
1433 * If the block does not appear in any reservation, then return the
1434 * block number unchanged. If it does appear in the reservation, then
1435 * keep looking through the tree of reservations in order to find the
1436 * first block number which is not reserved.
1437 */
1438
1439static u64 gfs2_next_unreserved_block(struct gfs2_rgrpd *rgd, u64 block,
1440                                      u32 length,
1441                                      const struct gfs2_inode *ip)
1442{
1443        struct gfs2_blkreserv *rs;
1444        struct rb_node *n;
1445        int rc;
1446
1447        spin_lock(&rgd->rd_rsspin);
1448        n = rgd->rd_rstree.rb_node;
1449        while (n) {
1450                rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
1451                rc = rs_cmp(block, length, rs);
1452                if (rc < 0)
1453                        n = n->rb_left;
1454                else if (rc > 0)
1455                        n = n->rb_right;
1456                else
1457                        break;
1458        }
1459
1460        if (n) {
1461                while ((rs_cmp(block, length, rs) == 0) && (ip->i_res != rs)) {
1462                        block = gfs2_rbm_to_block(&rs->rs_rbm) + rs->rs_free;
1463                        n = n->rb_right;
1464                        if (n == NULL)
1465                                break;
1466                        rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
1467                }
1468        }
1469
1470        spin_unlock(&rgd->rd_rsspin);
1471        return block;
1472}
1473
1474/**
1475 * gfs2_reservation_check_and_update - Check for reservations during block alloc
1476 * @rbm: The current position in the resource group
1477 * @ip: The inode for which we are searching for blocks
1478 * @minext: The minimum extent length
1479 *
1480 * This checks the current position in the rgrp to see whether there is
1481 * a reservation covering this block. If not then this function is a
1482 * no-op. If there is, then the position is moved to the end of the
1483 * contiguous reservation(s) so that we are pointing at the first
1484 * non-reserved block.
1485 *
1486 * Returns: 0 if no reservation, 1 if @rbm has changed, otherwise an error
1487 */
1488
1489static int gfs2_reservation_check_and_update(struct gfs2_rbm *rbm,
1490                                             const struct gfs2_inode *ip,
1491                                             u32 minext)
1492{
1493        u64 block = gfs2_rbm_to_block(rbm);
1494        u32 extlen = 1;
1495        u64 nblock;
1496        int ret;
1497
1498        /*
1499         * If we have a minimum extent length, then skip over any extent
1500         * which is less than the min extent length in size.
1501         */
1502        if (minext) {
1503                extlen = gfs2_free_extlen(rbm, minext);
1504                nblock = block + extlen;
1505                if (extlen < minext)
1506                        goto fail;
1507        }
1508
1509        /*
1510         * Check the extent which has been found against the reservations
1511         * and skip if parts of it are already reserved
1512         */
1513        nblock = gfs2_next_unreserved_block(rbm->rgd, block, extlen, ip);
1514        if (nblock == block)
1515                return 0;
1516fail:
1517        ret = gfs2_rbm_from_block(rbm, nblock);
1518        if (ret < 0)
1519                return ret;
1520        return 1;
1521}
1522
1523/**
1524 * gfs2_rbm_find - Look for blocks of a particular state
1525 * @rbm: Value/result starting position and final position
1526 * @state: The state which we want to find
1527 * @minext: The requested extent length (0 for a single block)
1528 * @ip: If set, check for reservations
1529 * @nowrap: Stop looking at the end of the rgrp, rather than wrapping
1530 *          around until we've reached the starting point.
1531 *
1532 * Side effects:
1533 * - If looking for free blocks, we set GBF_FULL on each bitmap which
1534 *   has no free blocks in it.
1535 *
1536 * Returns: 0 on success, -ENOSPC if there is no block of the requested state
1537 */
1538
1539static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 minext,
1540                         const struct gfs2_inode *ip, bool nowrap)
1541{
1542        struct buffer_head *bh;
1543        struct gfs2_bitmap *initial_bi;
1544        u32 initial_offset;
1545        u32 offset;
1546        u8 *buffer;
1547        int index;
1548        int n = 0;
1549        int iters = rbm->rgd->rd_length;
1550        int ret;
1551
1552        /* If we are not starting at the beginning of a bitmap, then we
1553         * need to add one to the bitmap count to ensure that we search
1554         * the starting bitmap twice.
1555         */
1556        if (rbm->offset != 0)
1557                iters++;
1558
1559        while(1) {
1560                if (test_bit(GBF_FULL, &rbm->bi->bi_flags) &&
1561                    (state == GFS2_BLKST_FREE))
1562                        goto next_bitmap;
1563
1564                bh = rbm->bi->bi_bh;
1565                buffer = bh->b_data + rbm->bi->bi_offset;
1566                WARN_ON(!buffer_uptodate(bh));
1567                if (state != GFS2_BLKST_UNLINKED && rbm->bi->bi_clone)
1568                        buffer = rbm->bi->bi_clone + rbm->bi->bi_offset;
1569                initial_offset = rbm->offset;
1570                offset = gfs2_bitfit(buffer, rbm->bi->bi_len, rbm->offset, state);
1571                if (offset == BFITNOENT)
1572                        goto bitmap_full;
1573                rbm->offset = offset;
1574                if (ip == NULL)
1575                        return 0;
1576
1577                initial_bi = rbm->bi;
1578                ret = gfs2_reservation_check_and_update(rbm, ip, minext);
1579                if (ret == 0)
1580                        return 0;
1581                if (ret > 0) {
1582                        n += (rbm->bi - initial_bi);
1583                        goto next_iter;
1584                }
1585                if (ret == -E2BIG) {
1586                        index = 0;
1587                        rbm->offset = 0;
1588                        n += (rbm->bi - initial_bi);
1589                        goto res_covered_end_of_rgrp;
1590                }
1591                return ret;
1592
1593bitmap_full:    /* Mark bitmap as full and fall through */
1594                if ((state == GFS2_BLKST_FREE) && initial_offset == 0)
1595                        set_bit(GBF_FULL, &rbm->bi->bi_flags);
1596
1597next_bitmap:    /* Find next bitmap in the rgrp */
1598                rbm->offset = 0;
1599                index = rbm->bi - rbm->rgd->rd_bits;
1600                index++;
1601                if (index == rbm->rgd->rd_length)
1602                        index = 0;
1603res_covered_end_of_rgrp:
1604                rbm->bi = &rbm->rgd->rd_bits[index];
1605                if ((index == 0) && nowrap)
1606                        break;
1607                n++;
1608next_iter:
1609                if (n >= iters)
1610                        break;
1611        }
1612
1613        return -ENOSPC;
1614}
1615
1616/**
1617 * try_rgrp_unlink - Look for any unlinked, allocated, but unused inodes
1618 * @rgd: The rgrp
1619 * @last_unlinked: block address of the last dinode we unlinked
1620 * @skip: block address we should explicitly not unlink
1621 *
1622 * Returns: 0 if no error
1623 *          The inode, if one has been found, in inode.
1624 */
1625
1626static void try_rgrp_unlink(struct gfs2_rgrpd *rgd, u64 *last_unlinked, u64 skip)
1627{
1628        u64 block;
1629        struct gfs2_sbd *sdp = rgd->rd_sbd;
1630        struct gfs2_glock *gl;
1631        struct gfs2_inode *ip;
1632        int error;
1633        int found = 0;
1634        struct gfs2_rbm rbm = { .rgd = rgd, .bi = rgd->rd_bits, .offset = 0 };
1635
1636        while (1) {
1637                down_write(&sdp->sd_log_flush_lock);
1638                error = gfs2_rbm_find(&rbm, GFS2_BLKST_UNLINKED, 0, NULL, true);
1639                up_write(&sdp->sd_log_flush_lock);
1640                if (error == -ENOSPC)
1641                        break;
1642                if (WARN_ON_ONCE(error))
1643                        break;
1644
1645                block = gfs2_rbm_to_block(&rbm);
1646                if (gfs2_rbm_from_block(&rbm, block + 1))
1647                        break;
1648                if (*last_unlinked != NO_BLOCK && block <= *last_unlinked)
1649                        continue;
1650                if (block == skip)
1651                        continue;
1652                *last_unlinked = block;
1653
1654                error = gfs2_glock_get(sdp, block, &gfs2_inode_glops, CREATE, &gl);
1655                if (error)
1656                        continue;
1657
1658                /* If the inode is already in cache, we can ignore it here
1659                 * because the existing inode disposal code will deal with
1660                 * it when all refs have gone away. Accessing gl_object like
1661                 * this is not safe in general. Here it is ok because we do
1662                 * not dereference the pointer, and we only need an approx
1663                 * answer to whether it is NULL or not.
1664                 */
1665                ip = gl->gl_object;
1666
1667                if (ip || queue_work(gfs2_delete_workqueue, &gl->gl_delete) == 0)
1668                        gfs2_glock_put(gl);
1669                else
1670                        found++;
1671
1672                /* Limit reclaim to sensible number of tasks */
1673                if (found > NR_CPUS)
1674                        return;
1675        }
1676
1677        rgd->rd_flags &= ~GFS2_RDF_CHECK;
1678        return;
1679}
1680
1681static bool gfs2_select_rgrp(struct gfs2_rgrpd **pos, const struct gfs2_rgrpd *begin)
1682{
1683        struct gfs2_rgrpd *rgd = *pos;
1684
1685        rgd = gfs2_rgrpd_get_next(rgd);
1686        if (rgd == NULL)
1687                rgd = gfs2_rgrpd_get_next(NULL);
1688        *pos = rgd;
1689        if (rgd != begin) /* If we didn't wrap */
1690                return true;
1691        return false;
1692}
1693
1694/**
1695 * gfs2_inplace_reserve - Reserve space in the filesystem
1696 * @ip: the inode to reserve space for
1697 * @requested: the number of blocks to be reserved
1698 *
1699 * Returns: errno
1700 */
1701
1702int gfs2_inplace_reserve(struct gfs2_inode *ip, u32 requested)
1703{
1704        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1705        struct gfs2_rgrpd *begin = NULL;
1706        struct gfs2_blkreserv *rs = ip->i_res;
1707        int error = 0, rg_locked, flags = LM_FLAG_TRY;
1708        u64 last_unlinked = NO_BLOCK;
1709        int loops = 0;
1710
1711        if (sdp->sd_args.ar_rgrplvb)
1712                flags |= GL_SKIP;
1713        if (gfs2_assert_warn(sdp, requested))
1714                return -EINVAL;
1715        if (gfs2_rs_active(rs)) {
1716                begin = rs->rs_rbm.rgd;
1717                flags = 0; /* Yoda: Do or do not. There is no try */
1718        } else if (ip->i_rgd && rgrp_contains_block(ip->i_rgd, ip->i_goal)) {
1719                rs->rs_rbm.rgd = begin = ip->i_rgd;
1720        } else {
1721                rs->rs_rbm.rgd = begin = gfs2_blk2rgrpd(sdp, ip->i_goal, 1);
1722        }
1723        if (rs->rs_rbm.rgd == NULL)
1724                return -EBADSLT;
1725
1726        while (loops < 3) {
1727                rg_locked = 1;
1728
1729                if (!gfs2_glock_is_locked_by_me(rs->rs_rbm.rgd->rd_gl)) {
1730                        rg_locked = 0;
1731                        error = gfs2_glock_nq_init(rs->rs_rbm.rgd->rd_gl,
1732                                                   LM_ST_EXCLUSIVE, flags,
1733                                                   &rs->rs_rgd_gh);
1734                        if (error == GLR_TRYFAILED)
1735                                goto next_rgrp;
1736                        if (unlikely(error))
1737                                return error;
1738                        if (sdp->sd_args.ar_rgrplvb) {
1739                                error = update_rgrp_lvb(rs->rs_rbm.rgd);
1740                                if (unlikely(error)) {
1741                                        gfs2_glock_dq_uninit(&rs->rs_rgd_gh);
1742                                        return error;
1743                                }
1744                        }
1745                }
1746
1747                /* Skip unuseable resource groups */
1748                if (rs->rs_rbm.rgd->rd_flags & (GFS2_RGF_NOALLOC | GFS2_RDF_ERROR))
1749                        goto skip_rgrp;
1750
1751                if (sdp->sd_args.ar_rgrplvb)
1752                        gfs2_rgrp_bh_get(rs->rs_rbm.rgd);
1753
1754                /* Get a reservation if we don't already have one */
1755                if (!gfs2_rs_active(rs))
1756                        rg_mblk_search(rs->rs_rbm.rgd, ip, requested);
1757
1758                /* Skip rgrps when we can't get a reservation on first pass */
1759                if (!gfs2_rs_active(rs) && (loops < 1))
1760                        goto check_rgrp;
1761
1762                /* If rgrp has enough free space, use it */
1763                if (rs->rs_rbm.rgd->rd_free_clone >= requested) {
1764                        ip->i_rgd = rs->rs_rbm.rgd;
1765                        return 0;
1766                }
1767
1768                /* Drop reservation, if we couldn't use reserved rgrp */
1769                if (gfs2_rs_active(rs))
1770                        gfs2_rs_deltree(ip, rs);
1771check_rgrp:
1772                /* Check for unlinked inodes which can be reclaimed */
1773                if (rs->rs_rbm.rgd->rd_flags & GFS2_RDF_CHECK)
1774                        try_rgrp_unlink(rs->rs_rbm.rgd, &last_unlinked,
1775                                        ip->i_no_addr);
1776skip_rgrp:
1777                /* Unlock rgrp if required */
1778                if (!rg_locked)
1779                        gfs2_glock_dq_uninit(&rs->rs_rgd_gh);
1780next_rgrp:
1781                /* Find the next rgrp, and continue looking */
1782                if (gfs2_select_rgrp(&rs->rs_rbm.rgd, begin))
1783                        continue;
1784
1785                /* If we've scanned all the rgrps, but found no free blocks
1786                 * then this checks for some less likely conditions before
1787                 * trying again.
1788                 */
1789                flags &= ~LM_FLAG_TRY;
1790                loops++;
1791                /* Check that fs hasn't grown if writing to rindex */
1792                if (ip == GFS2_I(sdp->sd_rindex) && !sdp->sd_rindex_uptodate) {
1793                        error = gfs2_ri_update(ip);
1794                        if (error)
1795                                return error;
1796                }
1797                /* Flushing the log may release space */
1798                if (loops == 2)
1799                        gfs2_log_flush(sdp, NULL);
1800        }
1801
1802        return -ENOSPC;
1803}
1804
1805/**
1806 * gfs2_inplace_release - release an inplace reservation
1807 * @ip: the inode the reservation was taken out on
1808 *
1809 * Release a reservation made by gfs2_inplace_reserve().
1810 */
1811
1812void gfs2_inplace_release(struct gfs2_inode *ip)
1813{
1814        struct gfs2_blkreserv *rs = ip->i_res;
1815
1816        if (rs->rs_rgd_gh.gh_gl)
1817                gfs2_glock_dq_uninit(&rs->rs_rgd_gh);
1818}
1819
1820/**
1821 * gfs2_get_block_type - Check a block in a RG is of given type
1822 * @rgd: the resource group holding the block
1823 * @block: the block number
1824 *
1825 * Returns: The block type (GFS2_BLKST_*)
1826 */
1827
1828static unsigned char gfs2_get_block_type(struct gfs2_rgrpd *rgd, u64 block)
1829{
1830        struct gfs2_rbm rbm = { .rgd = rgd, };
1831        int ret;
1832
1833        ret = gfs2_rbm_from_block(&rbm, block);
1834        WARN_ON_ONCE(ret != 0);
1835
1836        return gfs2_testbit(&rbm);
1837}
1838
1839
1840/**
1841 * gfs2_alloc_extent - allocate an extent from a given bitmap
1842 * @rbm: the resource group information
1843 * @dinode: TRUE if the first block we allocate is for a dinode
1844 * @n: The extent length (value/result)
1845 *
1846 * Add the bitmap buffer to the transaction.
1847 * Set the found bits to @new_state to change block's allocation state.
1848 */
1849static void gfs2_alloc_extent(const struct gfs2_rbm *rbm, bool dinode,
1850                             unsigned int *n)
1851{
1852        struct gfs2_rbm pos = { .rgd = rbm->rgd, };
1853        const unsigned int elen = *n;
1854        u64 block;
1855        int ret;
1856
1857        *n = 1;
1858        block = gfs2_rbm_to_block(rbm);
1859        gfs2_trans_add_bh(rbm->rgd->rd_gl, rbm->bi->bi_bh, 1);
1860        gfs2_setbit(rbm, true, dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED);
1861        block++;
1862        while (*n < elen) {
1863                ret = gfs2_rbm_from_block(&pos, block);
1864                if (ret || gfs2_testbit(&pos) != GFS2_BLKST_FREE)
1865                        break;
1866                gfs2_trans_add_bh(pos.rgd->rd_gl, pos.bi->bi_bh, 1);
1867                gfs2_setbit(&pos, true, GFS2_BLKST_USED);
1868                (*n)++;
1869                block++;
1870        }
1871}
1872
1873/**
1874 * rgblk_free - Change alloc state of given block(s)
1875 * @sdp: the filesystem
1876 * @bstart: the start of a run of blocks to free
1877 * @blen: the length of the block run (all must lie within ONE RG!)
1878 * @new_state: GFS2_BLKST_XXX the after-allocation block state
1879 *
1880 * Returns:  Resource group containing the block(s)
1881 */
1882
1883static struct gfs2_rgrpd *rgblk_free(struct gfs2_sbd *sdp, u64 bstart,
1884                                     u32 blen, unsigned char new_state)
1885{
1886        struct gfs2_rbm rbm;
1887
1888        rbm.rgd = gfs2_blk2rgrpd(sdp, bstart, 1);
1889        if (!rbm.rgd) {
1890                if (gfs2_consist(sdp))
1891                        fs_err(sdp, "block = %llu\n", (unsigned long long)bstart);
1892                return NULL;
1893        }
1894
1895        while (blen--) {
1896                gfs2_rbm_from_block(&rbm, bstart);
1897                bstart++;
1898                if (!rbm.bi->bi_clone) {
1899                        rbm.bi->bi_clone = kmalloc(rbm.bi->bi_bh->b_size,
1900                                                   GFP_NOFS | __GFP_NOFAIL);
1901                        memcpy(rbm.bi->bi_clone + rbm.bi->bi_offset,
1902                               rbm.bi->bi_bh->b_data + rbm.bi->bi_offset,
1903                               rbm.bi->bi_len);
1904                }
1905                gfs2_trans_add_bh(rbm.rgd->rd_gl, rbm.bi->bi_bh, 1);
1906                gfs2_setbit(&rbm, false, new_state);
1907        }
1908
1909        return rbm.rgd;
1910}
1911
1912/**
1913 * gfs2_rgrp_dump - print out an rgrp
1914 * @seq: The iterator
1915 * @gl: The glock in question
1916 *
1917 */
1918
1919int gfs2_rgrp_dump(struct seq_file *seq, const struct gfs2_glock *gl)
1920{
1921        struct gfs2_rgrpd *rgd = gl->gl_object;
1922        struct gfs2_blkreserv *trs;
1923        const struct rb_node *n;
1924
1925        if (rgd == NULL)
1926                return 0;
1927        gfs2_print_dbg(seq, " R: n:%llu f:%02x b:%u/%u i:%u r:%u\n",
1928                       (unsigned long long)rgd->rd_addr, rgd->rd_flags,
1929                       rgd->rd_free, rgd->rd_free_clone, rgd->rd_dinodes,
1930                       rgd->rd_reserved);
1931        spin_lock(&rgd->rd_rsspin);
1932        for (n = rb_first(&rgd->rd_rstree); n; n = rb_next(&trs->rs_node)) {
1933                trs = rb_entry(n, struct gfs2_blkreserv, rs_node);
1934                dump_rs(seq, trs);
1935        }
1936        spin_unlock(&rgd->rd_rsspin);
1937        return 0;
1938}
1939
1940static void gfs2_rgrp_error(struct gfs2_rgrpd *rgd)
1941{
1942        struct gfs2_sbd *sdp = rgd->rd_sbd;
1943        fs_warn(sdp, "rgrp %llu has an error, marking it readonly until umount\n",
1944                (unsigned long long)rgd->rd_addr);
1945        fs_warn(sdp, "umount on all nodes and run fsck.gfs2 to fix the error\n");
1946        gfs2_rgrp_dump(NULL, rgd->rd_gl);
1947        rgd->rd_flags |= GFS2_RDF_ERROR;
1948}
1949
1950/**
1951 * gfs2_adjust_reservation - Adjust (or remove) a reservation after allocation
1952 * @ip: The inode we have just allocated blocks for
1953 * @rbm: The start of the allocated blocks
1954 * @len: The extent length
1955 *
1956 * Adjusts a reservation after an allocation has taken place. If the
1957 * reservation does not match the allocation, or if it is now empty
1958 * then it is removed.
1959 */
1960
1961static void gfs2_adjust_reservation(struct gfs2_inode *ip,
1962                                    const struct gfs2_rbm *rbm, unsigned len)
1963{
1964        struct gfs2_blkreserv *rs = ip->i_res;
1965        struct gfs2_rgrpd *rgd = rbm->rgd;
1966        unsigned rlen;
1967        u64 block;
1968        int ret;
1969
1970        spin_lock(&rgd->rd_rsspin);
1971        if (gfs2_rs_active(rs)) {
1972                if (gfs2_rbm_eq(&rs->rs_rbm, rbm)) {
1973                        block = gfs2_rbm_to_block(rbm);
1974                        ret = gfs2_rbm_from_block(&rs->rs_rbm, block + len);
1975                        rlen = min(rs->rs_free, len);
1976                        rs->rs_free -= rlen;
1977                        rgd->rd_reserved -= rlen;
1978                        trace_gfs2_rs(rs, TRACE_RS_CLAIM);
1979                        if (rs->rs_free && !ret)
1980                                goto out;
1981                }
1982                __rs_deltree(ip, rs);
1983        }
1984out:
1985        spin_unlock(&rgd->rd_rsspin);
1986}
1987
1988/**
1989 * gfs2_alloc_blocks - Allocate one or more blocks of data and/or a dinode
1990 * @ip: the inode to allocate the block for
1991 * @bn: Used to return the starting block number
1992 * @nblocks: requested number of blocks/extent length (value/result)
1993 * @dinode: 1 if we're allocating a dinode block, else 0
1994 * @generation: the generation number of the inode
1995 *
1996 * Returns: 0 or error
1997 */
1998
1999int gfs2_alloc_blocks(struct gfs2_inode *ip, u64 *bn, unsigned int *nblocks,
2000                      bool dinode, u64 *generation)
2001{
2002        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2003        struct buffer_head *dibh;
2004        struct gfs2_rbm rbm = { .rgd = ip->i_rgd, };
2005        unsigned int ndata;
2006        u64 goal;
2007        u64 block; /* block, within the file system scope */
2008        int error;
2009
2010        if (gfs2_rs_active(ip->i_res))
2011                goal = gfs2_rbm_to_block(&ip->i_res->rs_rbm);
2012        else if (!dinode && rgrp_contains_block(rbm.rgd, ip->i_goal))
2013                goal = ip->i_goal;
2014        else
2015                goal = rbm.rgd->rd_last_alloc + rbm.rgd->rd_data0;
2016
2017        gfs2_rbm_from_block(&rbm, goal);
2018        error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, 0, ip, false);
2019
2020        if (error == -ENOSPC) {
2021                gfs2_rbm_from_block(&rbm, goal);
2022                error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, 0, NULL, false);
2023        }
2024
2025        /* Since all blocks are reserved in advance, this shouldn't happen */
2026        if (error) {
2027                fs_warn(sdp, "inum=%llu error=%d, nblocks=%u, full=%d\n",
2028                        (unsigned long long)ip->i_no_addr, error, *nblocks,
2029                        test_bit(GBF_FULL, &rbm.rgd->rd_bits->bi_flags));
2030                goto rgrp_error;
2031        }
2032
2033        gfs2_alloc_extent(&rbm, dinode, nblocks);
2034        block = gfs2_rbm_to_block(&rbm);
2035        rbm.rgd->rd_last_alloc = block - rbm.rgd->rd_data0;
2036        if (gfs2_rs_active(ip->i_res))
2037                gfs2_adjust_reservation(ip, &rbm, *nblocks);
2038        ndata = *nblocks;
2039        if (dinode)
2040                ndata--;
2041
2042        if (!dinode) {
2043                ip->i_goal = block + ndata - 1;
2044                error = gfs2_meta_inode_buffer(ip, &dibh);
2045                if (error == 0) {
2046                        struct gfs2_dinode *di =
2047                                (struct gfs2_dinode *)dibh->b_data;
2048                        gfs2_trans_add_bh(ip->i_gl, dibh, 1);
2049                        di->di_goal_meta = di->di_goal_data =
2050                                cpu_to_be64(ip->i_goal);
2051                        brelse(dibh);
2052                }
2053        }
2054        if (rbm.rgd->rd_free < *nblocks) {
2055                printk(KERN_WARNING "nblocks=%u\n", *nblocks);
2056                goto rgrp_error;
2057        }
2058
2059        rbm.rgd->rd_free -= *nblocks;
2060        if (dinode) {
2061                rbm.rgd->rd_dinodes++;
2062                *generation = rbm.rgd->rd_igeneration++;
2063                if (*generation == 0)
2064                        *generation = rbm.rgd->rd_igeneration++;
2065        }
2066
2067        gfs2_trans_add_bh(rbm.rgd->rd_gl, rbm.rgd->rd_bits[0].bi_bh, 1);
2068        gfs2_rgrp_out(rbm.rgd, rbm.rgd->rd_bits[0].bi_bh->b_data);
2069        gfs2_rgrp_ondisk2lvb(rbm.rgd->rd_rgl, rbm.rgd->rd_bits[0].bi_bh->b_data);
2070
2071        gfs2_statfs_change(sdp, 0, -(s64)*nblocks, dinode ? 1 : 0);
2072        if (dinode)
2073                gfs2_trans_add_unrevoke(sdp, block, 1);
2074
2075        /*
2076         * This needs reviewing to see why we cannot do the quota change
2077         * at this point in the dinode case.
2078         */
2079        if (ndata)
2080                gfs2_quota_change(ip, ndata, ip->i_inode.i_uid,
2081                                  ip->i_inode.i_gid);
2082
2083        rbm.rgd->rd_free_clone -= *nblocks;
2084        trace_gfs2_block_alloc(ip, rbm.rgd, block, *nblocks,
2085                               dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED);
2086        *bn = block;
2087        return 0;
2088
2089rgrp_error:
2090        gfs2_rgrp_error(rbm.rgd);
2091        return -EIO;
2092}
2093
2094/**
2095 * __gfs2_free_blocks - free a contiguous run of block(s)
2096 * @ip: the inode these blocks are being freed from
2097 * @bstart: first block of a run of contiguous blocks
2098 * @blen: the length of the block run
2099 * @meta: 1 if the blocks represent metadata
2100 *
2101 */
2102
2103void __gfs2_free_blocks(struct gfs2_inode *ip, u64 bstart, u32 blen, int meta)
2104{
2105        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2106        struct gfs2_rgrpd *rgd;
2107
2108        rgd = rgblk_free(sdp, bstart, blen, GFS2_BLKST_FREE);
2109        if (!rgd)
2110                return;
2111        trace_gfs2_block_alloc(ip, rgd, bstart, blen, GFS2_BLKST_FREE);
2112        rgd->rd_free += blen;
2113        rgd->rd_flags &= ~GFS2_RGF_TRIMMED;
2114        gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
2115        gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2116        gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, rgd->rd_bits[0].bi_bh->b_data);
2117
2118        /* Directories keep their data in the metadata address space */
2119        if (meta || ip->i_depth)
2120                gfs2_meta_wipe(ip, bstart, blen);
2121}
2122
2123/**
2124 * gfs2_free_meta - free a contiguous run of data block(s)
2125 * @ip: the inode these blocks are being freed from
2126 * @bstart: first block of a run of contiguous blocks
2127 * @blen: the length of the block run
2128 *
2129 */
2130
2131void gfs2_free_meta(struct gfs2_inode *ip, u64 bstart, u32 blen)
2132{
2133        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2134
2135        __gfs2_free_blocks(ip, bstart, blen, 1);
2136        gfs2_statfs_change(sdp, 0, +blen, 0);
2137        gfs2_quota_change(ip, -(s64)blen, ip->i_inode.i_uid, ip->i_inode.i_gid);
2138}
2139
2140void gfs2_unlink_di(struct inode *inode)
2141{
2142        struct gfs2_inode *ip = GFS2_I(inode);
2143        struct gfs2_sbd *sdp = GFS2_SB(inode);
2144        struct gfs2_rgrpd *rgd;
2145        u64 blkno = ip->i_no_addr;
2146
2147        rgd = rgblk_free(sdp, blkno, 1, GFS2_BLKST_UNLINKED);
2148        if (!rgd)
2149                return;
2150        trace_gfs2_block_alloc(ip, rgd, blkno, 1, GFS2_BLKST_UNLINKED);
2151        gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
2152        gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2153        gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, rgd->rd_bits[0].bi_bh->b_data);
2154        update_rgrp_lvb_unlinked(rgd, 1);
2155}
2156
2157static void gfs2_free_uninit_di(struct gfs2_rgrpd *rgd, u64 blkno)
2158{
2159        struct gfs2_sbd *sdp = rgd->rd_sbd;
2160        struct gfs2_rgrpd *tmp_rgd;
2161
2162        tmp_rgd = rgblk_free(sdp, blkno, 1, GFS2_BLKST_FREE);
2163        if (!tmp_rgd)
2164                return;
2165        gfs2_assert_withdraw(sdp, rgd == tmp_rgd);
2166
2167        if (!rgd->rd_dinodes)
2168                gfs2_consist_rgrpd(rgd);
2169        rgd->rd_dinodes--;
2170        rgd->rd_free++;
2171
2172        gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
2173        gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2174        gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, rgd->rd_bits[0].bi_bh->b_data);
2175        update_rgrp_lvb_unlinked(rgd, -1);
2176
2177        gfs2_statfs_change(sdp, 0, +1, -1);
2178}
2179
2180
2181void gfs2_free_di(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip)
2182{
2183        gfs2_free_uninit_di(rgd, ip->i_no_addr);
2184        trace_gfs2_block_alloc(ip, rgd, ip->i_no_addr, 1, GFS2_BLKST_FREE);
2185        gfs2_quota_change(ip, -1, ip->i_inode.i_uid, ip->i_inode.i_gid);
2186        gfs2_meta_wipe(ip, ip->i_no_addr, 1);
2187}
2188
2189/**
2190 * gfs2_check_blk_type - Check the type of a block
2191 * @sdp: The superblock
2192 * @no_addr: The block number to check
2193 * @type: The block type we are looking for
2194 *
2195 * Returns: 0 if the block type matches the expected type
2196 *          -ESTALE if it doesn't match
2197 *          or -ve errno if something went wrong while checking
2198 */
2199
2200int gfs2_check_blk_type(struct gfs2_sbd *sdp, u64 no_addr, unsigned int type)
2201{
2202        struct gfs2_rgrpd *rgd;
2203        struct gfs2_holder rgd_gh;
2204        int error = -EINVAL;
2205
2206        rgd = gfs2_blk2rgrpd(sdp, no_addr, 1);
2207        if (!rgd)
2208                goto fail;
2209
2210        error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh);
2211        if (error)
2212                goto fail;
2213
2214        if (gfs2_get_block_type(rgd, no_addr) != type)
2215                error = -ESTALE;
2216
2217        gfs2_glock_dq_uninit(&rgd_gh);
2218fail:
2219        return error;
2220}
2221
2222/**
2223 * gfs2_rlist_add - add a RG to a list of RGs
2224 * @ip: the inode
2225 * @rlist: the list of resource groups
2226 * @block: the block
2227 *
2228 * Figure out what RG a block belongs to and add that RG to the list
2229 *
2230 * FIXME: Don't use NOFAIL
2231 *
2232 */
2233
2234void gfs2_rlist_add(struct gfs2_inode *ip, struct gfs2_rgrp_list *rlist,
2235                    u64 block)
2236{
2237        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2238        struct gfs2_rgrpd *rgd;
2239        struct gfs2_rgrpd **tmp;
2240        unsigned int new_space;
2241        unsigned int x;
2242
2243        if (gfs2_assert_warn(sdp, !rlist->rl_ghs))
2244                return;
2245
2246        if (ip->i_rgd && rgrp_contains_block(ip->i_rgd, block))
2247                rgd = ip->i_rgd;
2248        else
2249                rgd = gfs2_blk2rgrpd(sdp, block, 1);
2250        if (!rgd) {
2251                fs_err(sdp, "rlist_add: no rgrp for block %llu\n", (unsigned long long)block);
2252                return;
2253        }
2254        ip->i_rgd = rgd;
2255
2256        for (x = 0; x < rlist->rl_rgrps; x++)
2257                if (rlist->rl_rgd[x] == rgd)
2258                        return;
2259
2260        if (rlist->rl_rgrps == rlist->rl_space) {
2261                new_space = rlist->rl_space + 10;
2262
2263                tmp = kcalloc(new_space, sizeof(struct gfs2_rgrpd *),
2264                              GFP_NOFS | __GFP_NOFAIL);
2265
2266                if (rlist->rl_rgd) {
2267                        memcpy(tmp, rlist->rl_rgd,
2268                               rlist->rl_space * sizeof(struct gfs2_rgrpd *));
2269                        kfree(rlist->rl_rgd);
2270                }
2271
2272                rlist->rl_space = new_space;
2273                rlist->rl_rgd = tmp;
2274        }
2275
2276        rlist->rl_rgd[rlist->rl_rgrps++] = rgd;
2277}
2278
2279/**
2280 * gfs2_rlist_alloc - all RGs have been added to the rlist, now allocate
2281 *      and initialize an array of glock holders for them
2282 * @rlist: the list of resource groups
2283 * @state: the lock state to acquire the RG lock in
2284 *
2285 * FIXME: Don't use NOFAIL
2286 *
2287 */
2288
2289void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist, unsigned int state)
2290{
2291        unsigned int x;
2292
2293        rlist->rl_ghs = kcalloc(rlist->rl_rgrps, sizeof(struct gfs2_holder),
2294                                GFP_NOFS | __GFP_NOFAIL);
2295        for (x = 0; x < rlist->rl_rgrps; x++)
2296                gfs2_holder_init(rlist->rl_rgd[x]->rd_gl,
2297                                state, 0,
2298                                &rlist->rl_ghs[x]);
2299}
2300
2301/**
2302 * gfs2_rlist_free - free a resource group list
2303 * @list: the list of resource groups
2304 *
2305 */
2306
2307void gfs2_rlist_free(struct gfs2_rgrp_list *rlist)
2308{
2309        unsigned int x;
2310
2311        kfree(rlist->rl_rgd);
2312
2313        if (rlist->rl_ghs) {
2314                for (x = 0; x < rlist->rl_rgrps; x++)
2315                        gfs2_holder_uninit(&rlist->rl_ghs[x]);
2316                kfree(rlist->rl_ghs);
2317                rlist->rl_ghs = NULL;
2318        }
2319}
2320
2321
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