Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / nfs / blocklayout / dev.c
diff --git a/kernel/fs/nfs/blocklayout/dev.c b/kernel/fs/nfs/blocklayout/dev.c
new file mode 100644 (file)
index 0000000..e535599
--- /dev/null
@@ -0,0 +1,363 @@
+/*
+ * 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_rcu(dev, node.rcu);
+}
+
+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;
+}