| /* |
| * Copyright (c) 2014 Christoph Hellwig. |
| */ |
| #include <linux/sunrpc/svc.h> |
| #include <linux/blkdev.h> |
| #include <linux/nfs4.h> |
| #include <linux/nfs_fs.h> |
| #include <linux/nfs_xdr.h> |
| |
| #include "blocklayout.h" |
| |
| #define NFSDBG_FACILITY NFSDBG_PNFS_LD |
| |
| static void |
| bl_free_device(struct pnfs_block_dev *dev) |
| { |
| if (dev->nr_children) { |
| int i; |
| |
| for (i = 0; i < dev->nr_children; i++) |
| bl_free_device(&dev->children[i]); |
| kfree(dev->children); |
| } else { |
| if (dev->bdev) |
| blkdev_put(dev->bdev, FMODE_READ); |
| } |
| } |
| |
| void |
| bl_free_deviceid_node(struct nfs4_deviceid_node *d) |
| { |
| struct pnfs_block_dev *dev = |
| container_of(d, struct pnfs_block_dev, node); |
| |
| bl_free_device(dev); |
| kfree(dev); |
| } |
| |
| static int |
| nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b) |
| { |
| __be32 *p; |
| int i; |
| |
| p = xdr_inline_decode(xdr, 4); |
| if (!p) |
| return -EIO; |
| b->type = be32_to_cpup(p++); |
| |
| switch (b->type) { |
| case PNFS_BLOCK_VOLUME_SIMPLE: |
| p = xdr_inline_decode(xdr, 4); |
| if (!p) |
| return -EIO; |
| b->simple.nr_sigs = be32_to_cpup(p++); |
| if (!b->simple.nr_sigs) { |
| dprintk("no signature\n"); |
| return -EIO; |
| } |
| |
| b->simple.len = 4 + 4; |
| for (i = 0; i < b->simple.nr_sigs; i++) { |
| p = xdr_inline_decode(xdr, 8 + 4); |
| if (!p) |
| return -EIO; |
| p = xdr_decode_hyper(p, &b->simple.sigs[i].offset); |
| b->simple.sigs[i].sig_len = be32_to_cpup(p++); |
| |
| p = xdr_inline_decode(xdr, b->simple.sigs[i].sig_len); |
| if (!p) |
| return -EIO; |
| memcpy(&b->simple.sigs[i].sig, p, |
| b->simple.sigs[i].sig_len); |
| |
| b->simple.len += 8 + 4 + b->simple.sigs[i].sig_len; |
| } |
| break; |
| case PNFS_BLOCK_VOLUME_SLICE: |
| p = xdr_inline_decode(xdr, 8 + 8 + 4); |
| if (!p) |
| return -EIO; |
| p = xdr_decode_hyper(p, &b->slice.start); |
| p = xdr_decode_hyper(p, &b->slice.len); |
| b->slice.volume = be32_to_cpup(p++); |
| break; |
| case PNFS_BLOCK_VOLUME_CONCAT: |
| p = xdr_inline_decode(xdr, 4); |
| if (!p) |
| return -EIO; |
| b->concat.volumes_count = be32_to_cpup(p++); |
| |
| p = xdr_inline_decode(xdr, b->concat.volumes_count * 4); |
| if (!p) |
| return -EIO; |
| for (i = 0; i < b->concat.volumes_count; i++) |
| b->concat.volumes[i] = be32_to_cpup(p++); |
| break; |
| case PNFS_BLOCK_VOLUME_STRIPE: |
| p = xdr_inline_decode(xdr, 8 + 4); |
| if (!p) |
| return -EIO; |
| p = xdr_decode_hyper(p, &b->stripe.chunk_size); |
| b->stripe.volumes_count = be32_to_cpup(p++); |
| |
| p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4); |
| if (!p) |
| return -EIO; |
| for (i = 0; i < b->stripe.volumes_count; i++) |
| b->stripe.volumes[i] = be32_to_cpup(p++); |
| break; |
| default: |
| dprintk("unknown volume type!\n"); |
| return -EIO; |
| } |
| |
| return 0; |
| } |
| |
| static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset, |
| struct pnfs_block_dev_map *map) |
| { |
| map->start = dev->start; |
| map->len = dev->len; |
| map->disk_offset = dev->disk_offset; |
| map->bdev = dev->bdev; |
| return true; |
| } |
| |
| static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset, |
| struct pnfs_block_dev_map *map) |
| { |
| int i; |
| |
| for (i = 0; i < dev->nr_children; i++) { |
| struct pnfs_block_dev *child = &dev->children[i]; |
| |
| if (child->start > offset || |
| child->start + child->len <= offset) |
| continue; |
| |
| child->map(child, offset - child->start, map); |
| return true; |
| } |
| |
| dprintk("%s: ran off loop!\n", __func__); |
| return false; |
| } |
| |
| static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset, |
| struct pnfs_block_dev_map *map) |
| { |
| struct pnfs_block_dev *child; |
| u64 chunk; |
| u32 chunk_idx; |
| u64 disk_offset; |
| |
| chunk = div_u64(offset, dev->chunk_size); |
| div_u64_rem(chunk, dev->nr_children, &chunk_idx); |
| |
| if (chunk_idx > dev->nr_children) { |
| dprintk("%s: invalid chunk idx %d (%lld/%lld)\n", |
| __func__, chunk_idx, offset, dev->chunk_size); |
| /* error, should not happen */ |
| return false; |
| } |
| |
| /* truncate offset to the beginning of the stripe */ |
| offset = chunk * dev->chunk_size; |
| |
| /* disk offset of the stripe */ |
| disk_offset = div_u64(offset, dev->nr_children); |
| |
| child = &dev->children[chunk_idx]; |
| child->map(child, disk_offset, map); |
| |
| map->start += offset; |
| map->disk_offset += disk_offset; |
| map->len = dev->chunk_size; |
| return true; |
| } |
| |
| static int |
| bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d, |
| struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask); |
| |
| |
| static int |
| bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d, |
| struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) |
| { |
| struct pnfs_block_volume *v = &volumes[idx]; |
| dev_t dev; |
| |
| dev = bl_resolve_deviceid(server, v, gfp_mask); |
| if (!dev) |
| return -EIO; |
| |
| d->bdev = blkdev_get_by_dev(dev, FMODE_READ, NULL); |
| if (IS_ERR(d->bdev)) { |
| printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n", |
| MAJOR(dev), MINOR(dev), PTR_ERR(d->bdev)); |
| return PTR_ERR(d->bdev); |
| } |
| |
| |
| d->len = i_size_read(d->bdev->bd_inode); |
| d->map = bl_map_simple; |
| |
| printk(KERN_INFO "pNFS: using block device %s\n", |
| d->bdev->bd_disk->disk_name); |
| return 0; |
| } |
| |
| static int |
| bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d, |
| struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) |
| { |
| struct pnfs_block_volume *v = &volumes[idx]; |
| int ret; |
| |
| ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask); |
| if (ret) |
| return ret; |
| |
| d->disk_offset = v->slice.start; |
| d->len = v->slice.len; |
| return 0; |
| } |
| |
| static int |
| bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d, |
| struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) |
| { |
| struct pnfs_block_volume *v = &volumes[idx]; |
| u64 len = 0; |
| int ret, i; |
| |
| d->children = kcalloc(v->concat.volumes_count, |
| sizeof(struct pnfs_block_dev), GFP_KERNEL); |
| if (!d->children) |
| return -ENOMEM; |
| |
| for (i = 0; i < v->concat.volumes_count; i++) { |
| ret = bl_parse_deviceid(server, &d->children[i], |
| volumes, v->concat.volumes[i], gfp_mask); |
| if (ret) |
| return ret; |
| |
| d->nr_children++; |
| d->children[i].start += len; |
| len += d->children[i].len; |
| } |
| |
| d->len = len; |
| d->map = bl_map_concat; |
| return 0; |
| } |
| |
| static int |
| bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d, |
| struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) |
| { |
| struct pnfs_block_volume *v = &volumes[idx]; |
| u64 len = 0; |
| int ret, i; |
| |
| d->children = kcalloc(v->stripe.volumes_count, |
| sizeof(struct pnfs_block_dev), GFP_KERNEL); |
| if (!d->children) |
| return -ENOMEM; |
| |
| for (i = 0; i < v->stripe.volumes_count; i++) { |
| ret = bl_parse_deviceid(server, &d->children[i], |
| volumes, v->stripe.volumes[i], gfp_mask); |
| if (ret) |
| return ret; |
| |
| d->nr_children++; |
| len += d->children[i].len; |
| } |
| |
| d->len = len; |
| d->chunk_size = v->stripe.chunk_size; |
| d->map = bl_map_stripe; |
| return 0; |
| } |
| |
| static int |
| bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d, |
| struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) |
| { |
| switch (volumes[idx].type) { |
| case PNFS_BLOCK_VOLUME_SIMPLE: |
| return bl_parse_simple(server, d, volumes, idx, gfp_mask); |
| case PNFS_BLOCK_VOLUME_SLICE: |
| return bl_parse_slice(server, d, volumes, idx, gfp_mask); |
| case PNFS_BLOCK_VOLUME_CONCAT: |
| return bl_parse_concat(server, d, volumes, idx, gfp_mask); |
| case PNFS_BLOCK_VOLUME_STRIPE: |
| return bl_parse_stripe(server, d, volumes, idx, gfp_mask); |
| default: |
| dprintk("unsupported volume type: %d\n", volumes[idx].type); |
| return -EIO; |
| } |
| } |
| |
| struct nfs4_deviceid_node * |
| bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev, |
| gfp_t gfp_mask) |
| { |
| struct nfs4_deviceid_node *node = NULL; |
| struct pnfs_block_volume *volumes; |
| struct pnfs_block_dev *top; |
| struct xdr_stream xdr; |
| struct xdr_buf buf; |
| struct page *scratch; |
| int nr_volumes, ret, i; |
| __be32 *p; |
| |
| scratch = alloc_page(gfp_mask); |
| if (!scratch) |
| goto out; |
| |
| xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen); |
| xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE); |
| |
| p = xdr_inline_decode(&xdr, sizeof(__be32)); |
| if (!p) |
| goto out_free_scratch; |
| nr_volumes = be32_to_cpup(p++); |
| |
| volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume), |
| gfp_mask); |
| if (!volumes) |
| goto out_free_scratch; |
| |
| for (i = 0; i < nr_volumes; i++) { |
| ret = nfs4_block_decode_volume(&xdr, &volumes[i]); |
| if (ret < 0) |
| goto out_free_volumes; |
| } |
| |
| top = kzalloc(sizeof(*top), gfp_mask); |
| if (!top) |
| goto out_free_volumes; |
| |
| ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask); |
| if (ret) { |
| bl_free_device(top); |
| kfree(top); |
| goto out_free_volumes; |
| } |
| |
| node = &top->node; |
| nfs4_init_deviceid_node(node, server, &pdev->dev_id); |
| |
| out_free_volumes: |
| kfree(volumes); |
| out_free_scratch: |
| __free_page(scratch); |
| out: |
| return node; |
| } |