1 /* 2 * Copyright (c) 2014 Christoph Hellwig. 3 */ 4 #include <linux/sunrpc/svc.h> 5 #include <linux/blkdev.h> 6 #include <linux/nfs4.h> 7 #include <linux/nfs_fs.h> 8 #include <linux/nfs_xdr.h> 9 10 #include "blocklayout.h" 11 12 #define NFSDBG_FACILITY NFSDBG_PNFS_LD 13 14 static void 15 bl_free_device(struct pnfs_block_dev *dev) 16 { 17 if (dev->nr_children) { 18 int i; 19 20 for (i = 0; i < dev->nr_children; i++) 21 bl_free_device(&dev->children[i]); 22 kfree(dev->children); 23 } else { 24 if (dev->bdev) 25 blkdev_put(dev->bdev, FMODE_READ | FMODE_WRITE); 26 } 27 } 28 29 void 30 bl_free_deviceid_node(struct nfs4_deviceid_node *d) 31 { 32 struct pnfs_block_dev *dev = 33 container_of(d, struct pnfs_block_dev, node); 34 35 bl_free_device(dev); 36 kfree_rcu(dev, node.rcu); 37 } 38 39 static int 40 nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b) 41 { 42 __be32 *p; 43 int i; 44 45 p = xdr_inline_decode(xdr, 4); 46 if (!p) 47 return -EIO; 48 b->type = be32_to_cpup(p++); 49 50 switch (b->type) { 51 case PNFS_BLOCK_VOLUME_SIMPLE: 52 p = xdr_inline_decode(xdr, 4); 53 if (!p) 54 return -EIO; 55 b->simple.nr_sigs = be32_to_cpup(p++); 56 if (!b->simple.nr_sigs) { 57 dprintk("no signature\n"); 58 return -EIO; 59 } 60 61 b->simple.len = 4 + 4; 62 for (i = 0; i < b->simple.nr_sigs; i++) { 63 p = xdr_inline_decode(xdr, 8 + 4); 64 if (!p) 65 return -EIO; 66 p = xdr_decode_hyper(p, &b->simple.sigs[i].offset); 67 b->simple.sigs[i].sig_len = be32_to_cpup(p++); 68 if (b->simple.sigs[i].sig_len > PNFS_BLOCK_UUID_LEN) { 69 pr_info("signature too long: %d\n", 70 b->simple.sigs[i].sig_len); 71 return -EIO; 72 } 73 74 p = xdr_inline_decode(xdr, b->simple.sigs[i].sig_len); 75 if (!p) 76 return -EIO; 77 memcpy(&b->simple.sigs[i].sig, p, 78 b->simple.sigs[i].sig_len); 79 80 b->simple.len += 8 + 4 + b->simple.sigs[i].sig_len; 81 } 82 break; 83 case PNFS_BLOCK_VOLUME_SLICE: 84 p = xdr_inline_decode(xdr, 8 + 8 + 4); 85 if (!p) 86 return -EIO; 87 p = xdr_decode_hyper(p, &b->slice.start); 88 p = xdr_decode_hyper(p, &b->slice.len); 89 b->slice.volume = be32_to_cpup(p++); 90 break; 91 case PNFS_BLOCK_VOLUME_CONCAT: 92 p = xdr_inline_decode(xdr, 4); 93 if (!p) 94 return -EIO; 95 b->concat.volumes_count = be32_to_cpup(p++); 96 97 p = xdr_inline_decode(xdr, b->concat.volumes_count * 4); 98 if (!p) 99 return -EIO; 100 for (i = 0; i < b->concat.volumes_count; i++) 101 b->concat.volumes[i] = be32_to_cpup(p++); 102 break; 103 case PNFS_BLOCK_VOLUME_STRIPE: 104 p = xdr_inline_decode(xdr, 8 + 4); 105 if (!p) 106 return -EIO; 107 p = xdr_decode_hyper(p, &b->stripe.chunk_size); 108 b->stripe.volumes_count = be32_to_cpup(p++); 109 110 p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4); 111 if (!p) 112 return -EIO; 113 for (i = 0; i < b->stripe.volumes_count; i++) 114 b->stripe.volumes[i] = be32_to_cpup(p++); 115 break; 116 default: 117 dprintk("unknown volume type!\n"); 118 return -EIO; 119 } 120 121 return 0; 122 } 123 124 static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset, 125 struct pnfs_block_dev_map *map) 126 { 127 map->start = dev->start; 128 map->len = dev->len; 129 map->disk_offset = dev->disk_offset; 130 map->bdev = dev->bdev; 131 return true; 132 } 133 134 static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset, 135 struct pnfs_block_dev_map *map) 136 { 137 int i; 138 139 for (i = 0; i < dev->nr_children; i++) { 140 struct pnfs_block_dev *child = &dev->children[i]; 141 142 if (child->start > offset || 143 child->start + child->len <= offset) 144 continue; 145 146 child->map(child, offset - child->start, map); 147 return true; 148 } 149 150 dprintk("%s: ran off loop!\n", __func__); 151 return false; 152 } 153 154 static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset, 155 struct pnfs_block_dev_map *map) 156 { 157 struct pnfs_block_dev *child; 158 u64 chunk; 159 u32 chunk_idx; 160 u64 disk_offset; 161 162 chunk = div_u64(offset, dev->chunk_size); 163 div_u64_rem(chunk, dev->nr_children, &chunk_idx); 164 165 if (chunk_idx > dev->nr_children) { 166 dprintk("%s: invalid chunk idx %d (%lld/%lld)\n", 167 __func__, chunk_idx, offset, dev->chunk_size); 168 /* error, should not happen */ 169 return false; 170 } 171 172 /* truncate offset to the beginning of the stripe */ 173 offset = chunk * dev->chunk_size; 174 175 /* disk offset of the stripe */ 176 disk_offset = div_u64(offset, dev->nr_children); 177 178 child = &dev->children[chunk_idx]; 179 child->map(child, disk_offset, map); 180 181 map->start += offset; 182 map->disk_offset += disk_offset; 183 map->len = dev->chunk_size; 184 return true; 185 } 186 187 static int 188 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d, 189 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask); 190 191 192 static int 193 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d, 194 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 195 { 196 struct pnfs_block_volume *v = &volumes[idx]; 197 dev_t dev; 198 199 dev = bl_resolve_deviceid(server, v, gfp_mask); 200 if (!dev) 201 return -EIO; 202 203 d->bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_WRITE, NULL); 204 if (IS_ERR(d->bdev)) { 205 printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n", 206 MAJOR(dev), MINOR(dev), PTR_ERR(d->bdev)); 207 return PTR_ERR(d->bdev); 208 } 209 210 211 d->len = i_size_read(d->bdev->bd_inode); 212 d->map = bl_map_simple; 213 214 printk(KERN_INFO "pNFS: using block device %s\n", 215 d->bdev->bd_disk->disk_name); 216 return 0; 217 } 218 219 static int 220 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d, 221 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 222 { 223 struct pnfs_block_volume *v = &volumes[idx]; 224 int ret; 225 226 ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask); 227 if (ret) 228 return ret; 229 230 d->disk_offset = v->slice.start; 231 d->len = v->slice.len; 232 return 0; 233 } 234 235 static int 236 bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d, 237 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 238 { 239 struct pnfs_block_volume *v = &volumes[idx]; 240 u64 len = 0; 241 int ret, i; 242 243 d->children = kcalloc(v->concat.volumes_count, 244 sizeof(struct pnfs_block_dev), GFP_KERNEL); 245 if (!d->children) 246 return -ENOMEM; 247 248 for (i = 0; i < v->concat.volumes_count; i++) { 249 ret = bl_parse_deviceid(server, &d->children[i], 250 volumes, v->concat.volumes[i], gfp_mask); 251 if (ret) 252 return ret; 253 254 d->nr_children++; 255 d->children[i].start += len; 256 len += d->children[i].len; 257 } 258 259 d->len = len; 260 d->map = bl_map_concat; 261 return 0; 262 } 263 264 static int 265 bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d, 266 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 267 { 268 struct pnfs_block_volume *v = &volumes[idx]; 269 u64 len = 0; 270 int ret, i; 271 272 d->children = kcalloc(v->stripe.volumes_count, 273 sizeof(struct pnfs_block_dev), GFP_KERNEL); 274 if (!d->children) 275 return -ENOMEM; 276 277 for (i = 0; i < v->stripe.volumes_count; i++) { 278 ret = bl_parse_deviceid(server, &d->children[i], 279 volumes, v->stripe.volumes[i], gfp_mask); 280 if (ret) 281 return ret; 282 283 d->nr_children++; 284 len += d->children[i].len; 285 } 286 287 d->len = len; 288 d->chunk_size = v->stripe.chunk_size; 289 d->map = bl_map_stripe; 290 return 0; 291 } 292 293 static int 294 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d, 295 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 296 { 297 switch (volumes[idx].type) { 298 case PNFS_BLOCK_VOLUME_SIMPLE: 299 return bl_parse_simple(server, d, volumes, idx, gfp_mask); 300 case PNFS_BLOCK_VOLUME_SLICE: 301 return bl_parse_slice(server, d, volumes, idx, gfp_mask); 302 case PNFS_BLOCK_VOLUME_CONCAT: 303 return bl_parse_concat(server, d, volumes, idx, gfp_mask); 304 case PNFS_BLOCK_VOLUME_STRIPE: 305 return bl_parse_stripe(server, d, volumes, idx, gfp_mask); 306 default: 307 dprintk("unsupported volume type: %d\n", volumes[idx].type); 308 return -EIO; 309 } 310 } 311 312 struct nfs4_deviceid_node * 313 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev, 314 gfp_t gfp_mask) 315 { 316 struct nfs4_deviceid_node *node = NULL; 317 struct pnfs_block_volume *volumes; 318 struct pnfs_block_dev *top; 319 struct xdr_stream xdr; 320 struct xdr_buf buf; 321 struct page *scratch; 322 int nr_volumes, ret, i; 323 __be32 *p; 324 325 scratch = alloc_page(gfp_mask); 326 if (!scratch) 327 goto out; 328 329 xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen); 330 xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE); 331 332 p = xdr_inline_decode(&xdr, sizeof(__be32)); 333 if (!p) 334 goto out_free_scratch; 335 nr_volumes = be32_to_cpup(p++); 336 337 volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume), 338 gfp_mask); 339 if (!volumes) 340 goto out_free_scratch; 341 342 for (i = 0; i < nr_volumes; i++) { 343 ret = nfs4_block_decode_volume(&xdr, &volumes[i]); 344 if (ret < 0) 345 goto out_free_volumes; 346 } 347 348 top = kzalloc(sizeof(*top), gfp_mask); 349 if (!top) 350 goto out_free_volumes; 351 352 ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask); 353 if (ret) { 354 bl_free_device(top); 355 kfree(top); 356 goto out_free_volumes; 357 } 358 359 node = &top->node; 360 nfs4_init_deviceid_node(node, server, &pdev->dev_id); 361 362 out_free_volumes: 363 kfree(volumes); 364 out_free_scratch: 365 __free_page(scratch); 366 out: 367 return node; 368 } 369