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); 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 69 p = xdr_inline_decode(xdr, b->simple.sigs[i].sig_len); 70 if (!p) 71 return -EIO; 72 memcpy(&b->simple.sigs[i].sig, p, 73 b->simple.sigs[i].sig_len); 74 75 b->simple.len += 8 + 4 + b->simple.sigs[i].sig_len; 76 } 77 break; 78 case PNFS_BLOCK_VOLUME_SLICE: 79 p = xdr_inline_decode(xdr, 8 + 8 + 4); 80 if (!p) 81 return -EIO; 82 p = xdr_decode_hyper(p, &b->slice.start); 83 p = xdr_decode_hyper(p, &b->slice.len); 84 b->slice.volume = be32_to_cpup(p++); 85 break; 86 case PNFS_BLOCK_VOLUME_CONCAT: 87 p = xdr_inline_decode(xdr, 4); 88 if (!p) 89 return -EIO; 90 b->concat.volumes_count = be32_to_cpup(p++); 91 92 p = xdr_inline_decode(xdr, b->concat.volumes_count * 4); 93 if (!p) 94 return -EIO; 95 for (i = 0; i < b->concat.volumes_count; i++) 96 b->concat.volumes[i] = be32_to_cpup(p++); 97 break; 98 case PNFS_BLOCK_VOLUME_STRIPE: 99 p = xdr_inline_decode(xdr, 8 + 4); 100 if (!p) 101 return -EIO; 102 p = xdr_decode_hyper(p, &b->stripe.chunk_size); 103 b->stripe.volumes_count = be32_to_cpup(p++); 104 105 p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4); 106 if (!p) 107 return -EIO; 108 for (i = 0; i < b->stripe.volumes_count; i++) 109 b->stripe.volumes[i] = be32_to_cpup(p++); 110 break; 111 default: 112 dprintk("unknown volume type!\n"); 113 return -EIO; 114 } 115 116 return 0; 117 } 118 119 static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset, 120 struct pnfs_block_dev_map *map) 121 { 122 map->start = dev->start; 123 map->len = dev->len; 124 map->disk_offset = dev->disk_offset; 125 map->bdev = dev->bdev; 126 return true; 127 } 128 129 static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset, 130 struct pnfs_block_dev_map *map) 131 { 132 int i; 133 134 for (i = 0; i < dev->nr_children; i++) { 135 struct pnfs_block_dev *child = &dev->children[i]; 136 137 if (child->start > offset || 138 child->start + child->len <= offset) 139 continue; 140 141 child->map(child, offset - child->start, map); 142 return true; 143 } 144 145 dprintk("%s: ran off loop!\n", __func__); 146 return false; 147 } 148 149 static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset, 150 struct pnfs_block_dev_map *map) 151 { 152 struct pnfs_block_dev *child; 153 u64 chunk; 154 u32 chunk_idx; 155 u64 disk_offset; 156 157 chunk = div_u64(offset, dev->chunk_size); 158 div_u64_rem(chunk, dev->nr_children, &chunk_idx); 159 160 if (chunk_idx > dev->nr_children) { 161 dprintk("%s: invalid chunk idx %d (%lld/%lld)\n", 162 __func__, chunk_idx, offset, dev->chunk_size); 163 /* error, should not happen */ 164 return false; 165 } 166 167 /* truncate offset to the beginning of the stripe */ 168 offset = chunk * dev->chunk_size; 169 170 /* disk offset of the stripe */ 171 disk_offset = div_u64(offset, dev->nr_children); 172 173 child = &dev->children[chunk_idx]; 174 child->map(child, disk_offset, map); 175 176 map->start += offset; 177 map->disk_offset += disk_offset; 178 map->len = dev->chunk_size; 179 return true; 180 } 181 182 static int 183 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d, 184 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask); 185 186 187 static int 188 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d, 189 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 190 { 191 struct pnfs_block_volume *v = &volumes[idx]; 192 dev_t dev; 193 194 dev = bl_resolve_deviceid(server, v, gfp_mask); 195 if (!dev) 196 return -EIO; 197 198 d->bdev = blkdev_get_by_dev(dev, FMODE_READ, NULL); 199 if (IS_ERR(d->bdev)) { 200 printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n", 201 MAJOR(dev), MINOR(dev), PTR_ERR(d->bdev)); 202 return PTR_ERR(d->bdev); 203 } 204 205 206 d->len = i_size_read(d->bdev->bd_inode); 207 d->map = bl_map_simple; 208 209 printk(KERN_INFO "pNFS: using block device %s\n", 210 d->bdev->bd_disk->disk_name); 211 return 0; 212 } 213 214 static int 215 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d, 216 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 217 { 218 struct pnfs_block_volume *v = &volumes[idx]; 219 int ret; 220 221 ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask); 222 if (ret) 223 return ret; 224 225 d->disk_offset = v->slice.start; 226 d->len = v->slice.len; 227 return 0; 228 } 229 230 static int 231 bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d, 232 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 233 { 234 struct pnfs_block_volume *v = &volumes[idx]; 235 u64 len = 0; 236 int ret, i; 237 238 d->children = kcalloc(v->concat.volumes_count, 239 sizeof(struct pnfs_block_dev), GFP_KERNEL); 240 if (!d->children) 241 return -ENOMEM; 242 243 for (i = 0; i < v->concat.volumes_count; i++) { 244 ret = bl_parse_deviceid(server, &d->children[i], 245 volumes, v->concat.volumes[i], gfp_mask); 246 if (ret) 247 return ret; 248 249 d->nr_children++; 250 d->children[i].start += len; 251 len += d->children[i].len; 252 } 253 254 d->len = len; 255 d->map = bl_map_concat; 256 return 0; 257 } 258 259 static int 260 bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d, 261 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 262 { 263 struct pnfs_block_volume *v = &volumes[idx]; 264 u64 len = 0; 265 int ret, i; 266 267 d->children = kcalloc(v->stripe.volumes_count, 268 sizeof(struct pnfs_block_dev), GFP_KERNEL); 269 if (!d->children) 270 return -ENOMEM; 271 272 for (i = 0; i < v->stripe.volumes_count; i++) { 273 ret = bl_parse_deviceid(server, &d->children[i], 274 volumes, v->stripe.volumes[i], gfp_mask); 275 if (ret) 276 return ret; 277 278 d->nr_children++; 279 len += d->children[i].len; 280 } 281 282 d->len = len; 283 d->chunk_size = v->stripe.chunk_size; 284 d->map = bl_map_stripe; 285 return 0; 286 } 287 288 static int 289 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d, 290 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) 291 { 292 switch (volumes[idx].type) { 293 case PNFS_BLOCK_VOLUME_SIMPLE: 294 return bl_parse_simple(server, d, volumes, idx, gfp_mask); 295 case PNFS_BLOCK_VOLUME_SLICE: 296 return bl_parse_slice(server, d, volumes, idx, gfp_mask); 297 case PNFS_BLOCK_VOLUME_CONCAT: 298 return bl_parse_concat(server, d, volumes, idx, gfp_mask); 299 case PNFS_BLOCK_VOLUME_STRIPE: 300 return bl_parse_stripe(server, d, volumes, idx, gfp_mask); 301 default: 302 dprintk("unsupported volume type: %d\n", volumes[idx].type); 303 return -EIO; 304 } 305 } 306 307 struct nfs4_deviceid_node * 308 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev, 309 gfp_t gfp_mask) 310 { 311 struct nfs4_deviceid_node *node = NULL; 312 struct pnfs_block_volume *volumes; 313 struct pnfs_block_dev *top; 314 struct xdr_stream xdr; 315 struct xdr_buf buf; 316 struct page *scratch; 317 int nr_volumes, ret, i; 318 __be32 *p; 319 320 scratch = alloc_page(gfp_mask); 321 if (!scratch) 322 goto out; 323 324 xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen); 325 xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE); 326 327 p = xdr_inline_decode(&xdr, sizeof(__be32)); 328 if (!p) 329 goto out_free_scratch; 330 nr_volumes = be32_to_cpup(p++); 331 332 volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume), 333 gfp_mask); 334 if (!volumes) 335 goto out_free_scratch; 336 337 for (i = 0; i < nr_volumes; i++) { 338 ret = nfs4_block_decode_volume(&xdr, &volumes[i]); 339 if (ret < 0) 340 goto out_free_volumes; 341 } 342 343 top = kzalloc(sizeof(*top), gfp_mask); 344 if (!top) 345 goto out_free_volumes; 346 347 ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask); 348 if (ret) { 349 bl_free_device(top); 350 kfree(top); 351 goto out_free_volumes; 352 } 353 354 node = &top->node; 355 nfs4_init_deviceid_node(node, server, &pdev->dev_id); 356 357 out_free_volumes: 358 kfree(volumes); 359 out_free_scratch: 360 __free_page(scratch); 361 out: 362 return node; 363 } 364