sys/dev/nand/nandsim_swap.c

   1 /*-
   2  * Copyright (C) 2009-2012 Semihalf
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28 __FBSDID("$FreeBSD$");
  29
  30 #include <sys/param.h>
  31 #include <sys/types.h>
  32 #include <sys/systm.h>
  33 #include <sys/malloc.h>
  34 #include <sys/queue.h>
  35 #include <sys/fcntl.h>
  36 #include <sys/proc.h>
  37 #include <sys/namei.h>
  38 #include <sys/lock.h>
  39 #include <sys/vnode.h>
  40 #include <sys/mount.h>
  41
  42 #include <dev/nand/nandsim_chip.h>
  43 #include <dev/nand/nandsim_swap.h>
  44
  45 static int  init_block_state(struct chip_swap *);
  46 static void destroy_block_state(struct chip_swap *);
  47
  48 static int  create_buffers(struct chip_swap *);
  49 static void destroy_buffers(struct chip_swap *);
  50
  51 static int  swap_file_open(struct chip_swap *, const char *);
  52 static void swap_file_close(struct chip_swap *);
  53 static int  swap_file_write(struct chip_swap *, struct block_state *);
  54 static int  swap_file_read(struct chip_swap *, struct block_state *);
  55
  56 #define CHIP_SWAP_CMODE         0600
  57 #define CHIP_SWAP_BLOCKSPACES   2
  58
  59 static int
  60 init_block_state(struct chip_swap *swap)
  61 {
  62         struct block_state *blk_state;
  63         int i;
  64
  65         if (swap == NULL)
  66                 return (-1);
  67
  68         blk_state = malloc(swap->nof_blks * sizeof(struct block_state),
  69             M_NANDSIM, M_WAITOK | M_ZERO);
  70
  71         for (i = 0; i < swap->nof_blks; i++)
  72                 blk_state[i].offset = 0xffffffff;
  73
  74         swap->blk_state = blk_state;
  75
  76         return (0);
  77 }
  78
  79 static void
  80 destroy_block_state(struct chip_swap *swap)
  81 {
  82
  83         if (swap == NULL)
  84                 return;
  85
  86         if (swap->blk_state != NULL)
  87                 free(swap->blk_state, M_NANDSIM);
  88 }
  89
  90 static int
  91 create_buffers(struct chip_swap *swap)
  92 {
  93         struct block_space *block_space;
  94         void *block;
  95         int i;
  96
  97         for (i = 0; i < CHIP_SWAP_BLOCKSPACES; i++) {
  98                 block_space = malloc(sizeof(*block_space), M_NANDSIM, M_WAITOK);
  99                 block = malloc(swap->blk_size, M_NANDSIM, M_WAITOK);
 100                 block_space->blk_ptr = block;
 101                 SLIST_INSERT_HEAD(&swap->free_bs, block_space, free_link);
 102                 nand_debug(NDBG_SIM,"created blk_space %p[%p]\n", block_space,
 103                     block);
 104         }
 105
 106         if (i == 0)
 107                 return (-1);
 108
 109         return (0);
 110 }
 111
 112 static void
 113 destroy_buffers(struct chip_swap *swap)
 114 {
 115         struct block_space *blk_space;
 116
 117         if (swap == NULL)
 118                 return;
 119
 120         blk_space = SLIST_FIRST(&swap->free_bs);
 121         while (blk_space) {
 122                 SLIST_REMOVE_HEAD(&swap->free_bs, free_link);
 123                 nand_debug(NDBG_SIM,"destroyed blk_space %p[%p]\n",
 124                     blk_space, blk_space->blk_ptr);
 125                 free(blk_space->blk_ptr, M_NANDSIM);
 126                 free(blk_space, M_NANDSIM);
 127                 blk_space = SLIST_FIRST(&swap->free_bs);
 128         }
 129
 130         blk_space = STAILQ_FIRST(&swap->used_bs);
 131         while (blk_space) {
 132                 STAILQ_REMOVE_HEAD(&swap->used_bs, used_link);
 133                 nand_debug(NDBG_SIM,"destroyed blk_space %p[%p]\n",
 134                     blk_space, blk_space->blk_ptr);
 135                 free(blk_space->blk_ptr, M_NANDSIM);
 136                 free(blk_space, M_NANDSIM);
 137                 blk_space = STAILQ_FIRST(&swap->used_bs);
 138         }
 139 }
 140
 141 static int
 142 swap_file_open(struct chip_swap *swap, const char *swap_file)
 143 {
 144         struct nameidata nd;
 145         int flags, error;
 146
 147         NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, swap_file,
 148             curthread);
 149
 150         flags = FWRITE | FREAD | O_NOFOLLOW | O_CREAT | O_TRUNC;
 151
 152         error = vn_open(&nd, &flags, CHIP_SWAP_CMODE, NULL);
 153         if (error) {
 154                 nand_debug(NDBG_SIM,"Cannot create swap file %s", swap_file);
 155                 NDFREE(&nd, NDF_ONLY_PNBUF);
 156                 return (error);
 157         }
 158
 159         swap->swap_cred = crhold(curthread->td_ucred);
 160         NDFREE(&nd, NDF_ONLY_PNBUF);
 161
 162         /* We just unlock so we hold a reference */
 163         VOP_UNLOCK(nd.ni_vp, 0);
 164
 165         swap->swap_vp = nd.ni_vp;
 166
 167         return (0);
 168 }
 169
 170 static void
 171 swap_file_close(struct chip_swap *swap)
 172 {
 173
 174         if (swap == NULL)
 175                 return;
 176
 177         if (swap->swap_vp == NULL)
 178                 return;
 179
 180         vn_close(swap->swap_vp, FWRITE, swap->swap_cred, curthread);
 181         crfree(swap->swap_cred);
 182 }
 183
 184 static int
 185 swap_file_write(struct chip_swap *swap, struct block_state *blk_state)
 186 {
 187         struct block_space *blk_space;
 188         struct thread *td;
 189         struct mount *mp;
 190         struct vnode *vp;
 191         struct uio auio;
 192         struct iovec aiov;
 193
 194         if (swap == NULL || blk_state == NULL)
 195                 return (-1);
 196
 197         blk_space = blk_state->blk_sp;
 198         if (blk_state->offset == -1) {
 199                 blk_state->offset = swap->swap_offset;
 200                 swap->swap_offset += swap->blk_size;
 201         }
 202
 203         nand_debug(NDBG_SIM,"saving %p[%p] at %x\n",
 204             blk_space, blk_space->blk_ptr, blk_state->offset);
 205
 206         bzero(&aiov, sizeof(aiov));
 207         bzero(&auio, sizeof(auio));
 208
 209         aiov.iov_base = blk_space->blk_ptr;
 210         aiov.iov_len = swap->blk_size;
 211         td = curthread;
 212         vp = swap->swap_vp;
 213
 214         auio.uio_iov = &aiov;
 215         auio.uio_offset = blk_state->offset;
 216         auio.uio_segflg = UIO_SYSSPACE;
 217         auio.uio_rw = UIO_WRITE;
 218         auio.uio_iovcnt = 1;
 219         auio.uio_resid = swap->blk_size;
 220         auio.uio_td = td;
 221
 222         vn_start_write(vp, &mp, V_WAIT);
 223         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
 224         VOP_WRITE(vp, &auio, IO_UNIT, swap->swap_cred);
 225         VOP_UNLOCK(vp, 0);
 226         vn_finished_write(mp);
 227
 228         return (0);
 229 }
 230
 231 static int
 232 swap_file_read(struct chip_swap *swap, struct block_state *blk_state)
 233 {
 234         struct block_space *blk_space;
 235         struct thread *td;
 236         struct vnode *vp;
 237         struct uio auio;
 238         struct iovec aiov;
 239
 240         if (swap == NULL || blk_state == NULL)
 241                 return (-1);
 242
 243         blk_space = blk_state->blk_sp;
 244
 245         nand_debug(NDBG_SIM,"restore %p[%p] at %x\n",
 246             blk_space, blk_space->blk_ptr, blk_state->offset);
 247
 248         bzero(&aiov, sizeof(aiov));
 249         bzero(&auio, sizeof(auio));
 250
 251         aiov.iov_base = blk_space->blk_ptr;
 252         aiov.iov_len = swap->blk_size;
 253         td = curthread;
 254         vp = swap->swap_vp;
 255
 256         auio.uio_iov = &aiov;
 257         auio.uio_offset = blk_state->offset;
 258         auio.uio_segflg = UIO_SYSSPACE;
 259         auio.uio_rw = UIO_READ;
 260         auio.uio_iovcnt = 1;
 261         auio.uio_resid = swap->blk_size;
 262         auio.uio_td = td;
 263
 264         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
 265         VOP_READ(vp, &auio, 0, swap->swap_cred);
 266         VOP_UNLOCK(vp, 0);
 267
 268         return (0);
 269 }
 270
 271 struct chip_swap *
 272 nandsim_swap_init(const char *swap_file, uint32_t nof_blks, uint32_t blk_size)
 273 {
 274         struct chip_swap *swap;
 275         int err = 0;
 276
 277         if ((swap_file == NULL) || (nof_blks == 0) || (blk_size == 0))
 278                 return (NULL);
 279
 280         swap = malloc(sizeof(*swap), M_NANDSIM, M_WAITOK | M_ZERO);
 281
 282         SLIST_INIT(&swap->free_bs);
 283         STAILQ_INIT(&swap->used_bs);
 284         swap->blk_size = blk_size;
 285         swap->nof_blks = nof_blks;
 286
 287         err = init_block_state(swap);
 288         if (err) {
 289                 nandsim_swap_destroy(swap);
 290                 return (NULL);
 291         }
 292
 293         err = create_buffers(swap);
 294         if (err) {
 295                 nandsim_swap_destroy(swap);
 296                 return (NULL);
 297         }
 298
 299         err = swap_file_open(swap, swap_file);
 300         if (err) {
 301                 nandsim_swap_destroy(swap);
 302                 return (NULL);
 303         }
 304
 305         return (swap);
 306 }
 307
 308 void
 309 nandsim_swap_destroy(struct chip_swap *swap)
 310 {
 311
 312         if (swap == NULL)
 313                 return;
 314
 315         destroy_block_state(swap);
 316         destroy_buffers(swap);
 317         swap_file_close(swap);
 318         free(swap, M_NANDSIM);
 319 }
 320
 321 struct block_space *
 322 get_bs(struct chip_swap *swap, uint32_t block, uint8_t writing)
 323 {
 324         struct block_state *blk_state, *old_blk_state = NULL;
 325         struct block_space *blk_space;
 326
 327         if (swap == NULL || (block >= swap->nof_blks))
 328                 return (NULL);
 329
 330         blk_state = &swap->blk_state[block];
 331         nand_debug(NDBG_SIM,"blk_state %x\n", blk_state->status);
 332
 333         if (blk_state->status & BLOCK_ALLOCATED) {
 334                 blk_space = blk_state->blk_sp;
 335         } else {
 336                 blk_space = SLIST_FIRST(&swap->free_bs);
 337                 if (blk_space) {
 338                         SLIST_REMOVE_HEAD(&swap->free_bs, free_link);
 339                         STAILQ_INSERT_TAIL(&swap->used_bs, blk_space,
 340                             used_link);
 341                 } else {
 342                         blk_space = STAILQ_FIRST(&swap->used_bs);
 343                         old_blk_state = blk_space->blk_state;
 344                         STAILQ_REMOVE_HEAD(&swap->used_bs, used_link);
 345                         STAILQ_INSERT_TAIL(&swap->used_bs, blk_space,
 346                             used_link);
 347                         if (old_blk_state->status & BLOCK_DIRTY) {
 348                                 swap_file_write(swap, old_blk_state);
 349                                 old_blk_state->status &= ~BLOCK_DIRTY;
 350                                 old_blk_state->status |= BLOCK_SWAPPED;
 351                         }
 352                 }
 353         }
 354
 355         if (blk_space == NULL)
 356                 return (NULL);
 357
 358         if (old_blk_state != NULL) {
 359                 old_blk_state->status &= ~BLOCK_ALLOCATED;
 360                 old_blk_state->blk_sp = NULL;
 361         }
 362
 363         blk_state->blk_sp = blk_space;
 364         blk_space->blk_state = blk_state;
 365
 366         if (!(blk_state->status & BLOCK_ALLOCATED)) {
 367                 if (blk_state->status & BLOCK_SWAPPED)
 368                         swap_file_read(swap, blk_state);
 369                 else
 370                         memset(blk_space->blk_ptr, 0xff, swap->blk_size);
 371                 blk_state->status |= BLOCK_ALLOCATED;
 372         }
 373
 374         if (writing)
 375                 blk_state->status |= BLOCK_DIRTY;
 376
 377         nand_debug(NDBG_SIM,"get_bs returned %p[%p] state %x\n", blk_space,
 378             blk_space->blk_ptr, blk_state->status);
 379
 380         return (blk_space);
 381 }