fs/nilfs2/direct.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * direct.c - NILFS direct block pointer.
   4  *
   5  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
   6  *
   7  * Written by Koji Sato.
   8  */
   9
  10 #include <linux/errno.h>
  11 #include "nilfs.h"
  12 #include "page.h"
  13 #include "direct.h"
  14 #include "alloc.h"
  15 #include "dat.h"
  16
  17 static inline __le64 *nilfs_direct_dptrs(const struct nilfs_bmap *direct)
  18 {
  19         return (__le64 *)
  20                 ((struct nilfs_direct_node *)direct->b_u.u_data + 1);
  21 }
  22
  23 static inline __u64
  24 nilfs_direct_get_ptr(const struct nilfs_bmap *direct, __u64 key)
  25 {
  26         return le64_to_cpu(*(nilfs_direct_dptrs(direct) + key));
  27 }
  28
  29 static inline void nilfs_direct_set_ptr(struct nilfs_bmap *direct,
  30                                         __u64 key, __u64 ptr)
  31 {
  32         *(nilfs_direct_dptrs(direct) + key) = cpu_to_le64(ptr);
  33 }
  34
  35 static int nilfs_direct_lookup(const struct nilfs_bmap *direct,
  36                                __u64 key, int level, __u64 *ptrp)
  37 {
  38         __u64 ptr;
  39
  40         if (key > NILFS_DIRECT_KEY_MAX || level != 1)
  41                 return -ENOENT;
  42         ptr = nilfs_direct_get_ptr(direct, key);
  43         if (ptr == NILFS_BMAP_INVALID_PTR)
  44                 return -ENOENT;
  45
  46         *ptrp = ptr;
  47         return 0;
  48 }
  49
  50 static int nilfs_direct_lookup_contig(const struct nilfs_bmap *direct,
  51                                       __u64 key, __u64 *ptrp,
  52                                       unsigned int maxblocks)
  53 {
  54         struct inode *dat = NULL;
  55         __u64 ptr, ptr2;
  56         sector_t blocknr;
  57         int ret, cnt;
  58
  59         if (key > NILFS_DIRECT_KEY_MAX)
  60                 return -ENOENT;
  61         ptr = nilfs_direct_get_ptr(direct, key);
  62         if (ptr == NILFS_BMAP_INVALID_PTR)
  63                 return -ENOENT;
  64
  65         if (NILFS_BMAP_USE_VBN(direct)) {
  66                 dat = nilfs_bmap_get_dat(direct);
  67                 ret = nilfs_dat_translate(dat, ptr, &blocknr);
  68                 if (ret < 0)
  69                         return ret;
  70                 ptr = blocknr;
  71         }
  72
  73         maxblocks = min_t(unsigned int, maxblocks,
  74                           NILFS_DIRECT_KEY_MAX - key + 1);
  75         for (cnt = 1; cnt < maxblocks &&
  76                      (ptr2 = nilfs_direct_get_ptr(direct, key + cnt)) !=
  77                      NILFS_BMAP_INVALID_PTR;
  78              cnt++) {
  79                 if (dat) {
  80                         ret = nilfs_dat_translate(dat, ptr2, &blocknr);
  81                         if (ret < 0)
  82                                 return ret;
  83                         ptr2 = blocknr;
  84                 }
  85                 if (ptr2 != ptr + cnt)
  86                         break;
  87         }
  88         *ptrp = ptr;
  89         return cnt;
  90 }
  91
  92 static __u64
  93 nilfs_direct_find_target_v(const struct nilfs_bmap *direct, __u64 key)
  94 {
  95         __u64 ptr;
  96
  97         ptr = nilfs_bmap_find_target_seq(direct, key);
  98         if (ptr != NILFS_BMAP_INVALID_PTR)
  99                 /* sequential access */
 100                 return ptr;
 101
 102         /* block group */
 103         return nilfs_bmap_find_target_in_group(direct);
 104 }
 105
 106 static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
 107 {
 108         union nilfs_bmap_ptr_req req;
 109         struct inode *dat = NULL;
 110         struct buffer_head *bh;
 111         int ret;
 112
 113         if (key > NILFS_DIRECT_KEY_MAX)
 114                 return -ENOENT;
 115         if (nilfs_direct_get_ptr(bmap, key) != NILFS_BMAP_INVALID_PTR)
 116                 return -EEXIST;
 117
 118         if (NILFS_BMAP_USE_VBN(bmap)) {
 119                 req.bpr_ptr = nilfs_direct_find_target_v(bmap, key);
 120                 dat = nilfs_bmap_get_dat(bmap);
 121         }
 122         ret = nilfs_bmap_prepare_alloc_ptr(bmap, &req, dat);
 123         if (!ret) {
 124                 /* ptr must be a pointer to a buffer head. */
 125                 bh = (struct buffer_head *)((unsigned long)ptr);
 126                 set_buffer_nilfs_volatile(bh);
 127
 128                 nilfs_bmap_commit_alloc_ptr(bmap, &req, dat);
 129                 nilfs_direct_set_ptr(bmap, key, req.bpr_ptr);
 130
 131                 if (!nilfs_bmap_dirty(bmap))
 132                         nilfs_bmap_set_dirty(bmap);
 133
 134                 if (NILFS_BMAP_USE_VBN(bmap))
 135                         nilfs_bmap_set_target_v(bmap, key, req.bpr_ptr);
 136
 137                 nilfs_inode_add_blocks(bmap->b_inode, 1);
 138         }
 139         return ret;
 140 }
 141
 142 static int nilfs_direct_delete(struct nilfs_bmap *bmap, __u64 key)
 143 {
 144         union nilfs_bmap_ptr_req req;
 145         struct inode *dat;
 146         int ret;
 147
 148         if (key > NILFS_DIRECT_KEY_MAX ||
 149             nilfs_direct_get_ptr(bmap, key) == NILFS_BMAP_INVALID_PTR)
 150                 return -ENOENT;
 151
 152         dat = NILFS_BMAP_USE_VBN(bmap) ? nilfs_bmap_get_dat(bmap) : NULL;
 153         req.bpr_ptr = nilfs_direct_get_ptr(bmap, key);
 154
 155         ret = nilfs_bmap_prepare_end_ptr(bmap, &req, dat);
 156         if (!ret) {
 157                 nilfs_bmap_commit_end_ptr(bmap, &req, dat);
 158                 nilfs_direct_set_ptr(bmap, key, NILFS_BMAP_INVALID_PTR);
 159                 nilfs_inode_sub_blocks(bmap->b_inode, 1);
 160         }
 161         return ret;
 162 }
 163
 164 static int nilfs_direct_seek_key(const struct nilfs_bmap *direct, __u64 start,
 165                                  __u64 *keyp)
 166 {
 167         __u64 key;
 168
 169         for (key = start; key <= NILFS_DIRECT_KEY_MAX; key++) {
 170                 if (nilfs_direct_get_ptr(direct, key) !=
 171                     NILFS_BMAP_INVALID_PTR) {
 172                         *keyp = key;
 173                         return 0;
 174                 }
 175         }
 176         return -ENOENT;
 177 }
 178
 179 static int nilfs_direct_last_key(const struct nilfs_bmap *direct, __u64 *keyp)
 180 {
 181         __u64 key, lastkey;
 182
 183         lastkey = NILFS_DIRECT_KEY_MAX + 1;
 184         for (key = NILFS_DIRECT_KEY_MIN; key <= NILFS_DIRECT_KEY_MAX; key++)
 185                 if (nilfs_direct_get_ptr(direct, key) !=
 186                     NILFS_BMAP_INVALID_PTR)
 187                         lastkey = key;
 188
 189         if (lastkey == NILFS_DIRECT_KEY_MAX + 1)
 190                 return -ENOENT;
 191
 192         *keyp = lastkey;
 193
 194         return 0;
 195 }
 196
 197 static int nilfs_direct_check_insert(const struct nilfs_bmap *bmap, __u64 key)
 198 {
 199         return key > NILFS_DIRECT_KEY_MAX;
 200 }
 201
 202 static int nilfs_direct_gather_data(struct nilfs_bmap *direct,
 203                                     __u64 *keys, __u64 *ptrs, int nitems)
 204 {
 205         __u64 key;
 206         __u64 ptr;
 207         int n;
 208
 209         if (nitems > NILFS_DIRECT_NBLOCKS)
 210                 nitems = NILFS_DIRECT_NBLOCKS;
 211         n = 0;
 212         for (key = 0; key < nitems; key++) {
 213                 ptr = nilfs_direct_get_ptr(direct, key);
 214                 if (ptr != NILFS_BMAP_INVALID_PTR) {
 215                         keys[n] = key;
 216                         ptrs[n] = ptr;
 217                         n++;
 218                 }
 219         }
 220         return n;
 221 }
 222
 223 int nilfs_direct_delete_and_convert(struct nilfs_bmap *bmap,
 224                                     __u64 key, __u64 *keys, __u64 *ptrs, int n)
 225 {
 226         __le64 *dptrs;
 227         int ret, i, j;
 228
 229         /* no need to allocate any resource for conversion */
 230
 231         /* delete */
 232         ret = bmap->b_ops->bop_delete(bmap, key);
 233         if (ret < 0)
 234                 return ret;
 235
 236         /* free resources */
 237         if (bmap->b_ops->bop_clear != NULL)
 238                 bmap->b_ops->bop_clear(bmap);
 239
 240         /* convert */
 241         dptrs = nilfs_direct_dptrs(bmap);
 242         for (i = 0, j = 0; i < NILFS_DIRECT_NBLOCKS; i++) {
 243                 if ((j < n) && (i == keys[j])) {
 244                         dptrs[i] = (i != key) ?
 245                                 cpu_to_le64(ptrs[j]) :
 246                                 NILFS_BMAP_INVALID_PTR;
 247                         j++;
 248                 } else
 249                         dptrs[i] = NILFS_BMAP_INVALID_PTR;
 250         }
 251
 252         nilfs_direct_init(bmap);
 253         return 0;
 254 }
 255
 256 static int nilfs_direct_propagate(struct nilfs_bmap *bmap,
 257                                   struct buffer_head *bh)
 258 {
 259         struct nilfs_palloc_req oldreq, newreq;
 260         struct inode *dat;
 261         __u64 key;
 262         __u64 ptr;
 263         int ret;
 264
 265         if (!NILFS_BMAP_USE_VBN(bmap))
 266                 return 0;
 267
 268         dat = nilfs_bmap_get_dat(bmap);
 269         key = nilfs_bmap_data_get_key(bmap, bh);
 270         ptr = nilfs_direct_get_ptr(bmap, key);
 271         if (!buffer_nilfs_volatile(bh)) {
 272                 oldreq.pr_entry_nr = ptr;
 273                 newreq.pr_entry_nr = ptr;
 274                 ret = nilfs_dat_prepare_update(dat, &oldreq, &newreq);
 275                 if (ret < 0)
 276                         return ret;
 277                 nilfs_dat_commit_update(dat, &oldreq, &newreq,
 278                                         bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
 279                 set_buffer_nilfs_volatile(bh);
 280                 nilfs_direct_set_ptr(bmap, key, newreq.pr_entry_nr);
 281         } else
 282                 ret = nilfs_dat_mark_dirty(dat, ptr);
 283
 284         return ret;
 285 }
 286
 287 static int nilfs_direct_assign_v(struct nilfs_bmap *direct,
 288                                  __u64 key, __u64 ptr,
 289                                  struct buffer_head **bh,
 290                                  sector_t blocknr,
 291                                  union nilfs_binfo *binfo)
 292 {
 293         struct inode *dat = nilfs_bmap_get_dat(direct);
 294         union nilfs_bmap_ptr_req req;
 295         int ret;
 296
 297         req.bpr_ptr = ptr;
 298         ret = nilfs_dat_prepare_start(dat, &req.bpr_req);
 299         if (!ret) {
 300                 nilfs_dat_commit_start(dat, &req.bpr_req, blocknr);
 301                 binfo->bi_v.bi_vblocknr = cpu_to_le64(ptr);
 302                 binfo->bi_v.bi_blkoff = cpu_to_le64(key);
 303         }
 304         return ret;
 305 }
 306
 307 static int nilfs_direct_assign_p(struct nilfs_bmap *direct,
 308                                  __u64 key, __u64 ptr,
 309                                  struct buffer_head **bh,
 310                                  sector_t blocknr,
 311                                  union nilfs_binfo *binfo)
 312 {
 313         nilfs_direct_set_ptr(direct, key, blocknr);
 314
 315         binfo->bi_dat.bi_blkoff = cpu_to_le64(key);
 316         binfo->bi_dat.bi_level = 0;
 317
 318         return 0;
 319 }
 320
 321 static int nilfs_direct_assign(struct nilfs_bmap *bmap,
 322                                struct buffer_head **bh,
 323                                sector_t blocknr,
 324                                union nilfs_binfo *binfo)
 325 {
 326         __u64 key;
 327         __u64 ptr;
 328
 329         key = nilfs_bmap_data_get_key(bmap, *bh);
 330         if (unlikely(key > NILFS_DIRECT_KEY_MAX)) {
 331                 nilfs_msg(bmap->b_inode->i_sb, KERN_CRIT,
 332                           "%s (ino=%lu): invalid key: %llu", __func__,
 333                           bmap->b_inode->i_ino, (unsigned long long)key);
 334                 return -EINVAL;
 335         }
 336         ptr = nilfs_direct_get_ptr(bmap, key);
 337         if (unlikely(ptr == NILFS_BMAP_INVALID_PTR)) {
 338                 nilfs_msg(bmap->b_inode->i_sb, KERN_CRIT,
 339                           "%s (ino=%lu): invalid pointer: %llu", __func__,
 340                           bmap->b_inode->i_ino, (unsigned long long)ptr);
 341                 return -EINVAL;
 342         }
 343
 344         return NILFS_BMAP_USE_VBN(bmap) ?
 345                 nilfs_direct_assign_v(bmap, key, ptr, bh, blocknr, binfo) :
 346                 nilfs_direct_assign_p(bmap, key, ptr, bh, blocknr, binfo);
 347 }
 348
 349 static const struct nilfs_bmap_operations nilfs_direct_ops = {
 350         .bop_lookup             =       nilfs_direct_lookup,
 351         .bop_lookup_contig      =       nilfs_direct_lookup_contig,
 352         .bop_insert             =       nilfs_direct_insert,
 353         .bop_delete             =       nilfs_direct_delete,
 354         .bop_clear              =       NULL,
 355
 356         .bop_propagate          =       nilfs_direct_propagate,
 357
 358         .bop_lookup_dirty_buffers       =       NULL,
 359
 360         .bop_assign             =       nilfs_direct_assign,
 361         .bop_mark               =       NULL,
 362
 363         .bop_seek_key           =       nilfs_direct_seek_key,
 364         .bop_last_key           =       nilfs_direct_last_key,
 365
 366         .bop_check_insert       =       nilfs_direct_check_insert,
 367         .bop_check_delete       =       NULL,
 368         .bop_gather_data        =       nilfs_direct_gather_data,
 369 };
 370
 371
 372 int nilfs_direct_init(struct nilfs_bmap *bmap)
 373 {
 374         bmap->b_ops = &nilfs_direct_ops;
 375         return 0;
 376 }