[deliverable/linux.git] / fs / nfs / blocklayout / dev.c

/*
 * Copyright (c) 2014-2016 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 <linux/pr.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->pr_registered) {
			const struct pr_ops *ops =
				dev->bdev->bd_disk->fops->pr_ops;
			int error;

			error = ops->pr_register(dev->bdev, dev->pr_key, 0,
				false);
			if (error)
				pr_err("failed to unregister PR key.\n");
		}

		if (dev->bdev)
			blkdev_put(dev->bdev, FMODE_READ | FMODE_WRITE);
	}
}

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 || b->simple.nr_sigs > PNFS_BLOCK_MAX_UUIDS) {
			dprintk("Bad signature count: %d\n", b->simple.nr_sigs);
			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++);
			if (b->simple.sigs[i].sig_len > PNFS_BLOCK_UUID_LEN) {
				pr_info("signature too long: %d\n",
					b->simple.sigs[i].sig_len);
				return -EIO;
			}

			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 + \
				(XDR_QUADLEN(b->simple.sigs[i].sig_len) << 2);
		}
		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++);
		if (b->concat.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
			dprintk("Too many volumes: %d\n", b->concat.volumes_count);
			return -EIO;
		}

		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++);
		if (b->stripe.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
			dprintk("Too many volumes: %d\n", b->stripe.volumes_count);
			return -EIO;
		}

		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;
	case PNFS_BLOCK_VOLUME_SCSI:
		p = xdr_inline_decode(xdr, 4 + 4 + 4);
		if (!p)
			return -EIO;
		b->scsi.code_set = be32_to_cpup(p++);
		b->scsi.designator_type = be32_to_cpup(p++);
		b->scsi.designator_len = be32_to_cpup(p++);
		p = xdr_inline_decode(xdr, b->scsi.designator_len);
		if (!p)
			return -EIO;
		if (b->scsi.designator_len > 256)
			return -EIO;
		memcpy(&b->scsi.designator, p, b->scsi.designator_len);
		p = xdr_inline_decode(xdr, 8);
		if (!p)
			return -EIO;
		p = xdr_decode_hyper(p, &b->scsi.pr_key);
		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];
	struct block_device *bdev;
	dev_t dev;

	dev = bl_resolve_deviceid(server, v, gfp_mask);
	if (!dev)
		return -EIO;

	bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_WRITE, NULL);
	if (IS_ERR(bdev)) {
		printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
			MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
		return PTR_ERR(bdev);
	}
	d->bdev = 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 bool
bl_validate_designator(struct pnfs_block_volume *v)
{
	switch (v->scsi.designator_type) {
	case PS_DESIGNATOR_EUI64:
		if (v->scsi.code_set != PS_CODE_SET_BINARY)
			return false;

		if (v->scsi.designator_len != 8 &&
		    v->scsi.designator_len != 10 &&
		    v->scsi.designator_len != 16)
			return false;

		return true;
	case PS_DESIGNATOR_NAA:
		if (v->scsi.code_set != PS_CODE_SET_BINARY)
			return false;

		if (v->scsi.designator_len != 8 &&
		    v->scsi.designator_len != 16)
			return false;

		return true;
	case PS_DESIGNATOR_T10:
	case PS_DESIGNATOR_NAME:
		pr_err("pNFS: unsupported designator "
			"(code set %d, type %d, len %d.\n",
			v->scsi.code_set,
			v->scsi.designator_type,
			v->scsi.designator_len);
		return false;
	default:
		pr_err("pNFS: invalid designator "
			"(code set %d, type %d, len %d.\n",
			v->scsi.code_set,
			v->scsi.designator_type,
			v->scsi.designator_len);
		return false;
	}
}

/*
 * Try to open the udev path for the WWN.  At least on Debian the udev
 * by-id path will always point to the dm-multipath device if one exists.
 */
static struct block_device *
bl_open_udev_path(struct pnfs_block_volume *v)
{
	struct block_device *bdev;
	const char *devname;

	devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%*phN",
				v->scsi.designator_len, v->scsi.designator);
	if (!devname)
		return ERR_PTR(-ENOMEM);

	bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL);
	if (IS_ERR(bdev)) {
		pr_warn("pNFS: failed to open device %s (%ld)\n",
			devname, PTR_ERR(bdev));
	}

	kfree(devname);
	return bdev;
}

/*
 * Try to open the RH/Fedora specific dm-mpath udev path for this WWN, as the
 * wwn- links will only point to the first discovered SCSI device there.
 */
static struct block_device *
bl_open_dm_mpath_udev_path(struct pnfs_block_volume *v)
{
	struct block_device *bdev;
	const char *devname;

	devname = kasprintf(GFP_KERNEL,
			"/dev/disk/by-id/dm-uuid-mpath-%d%*phN",
			v->scsi.designator_type,
			v->scsi.designator_len, v->scsi.designator);
	if (!devname)
		return ERR_PTR(-ENOMEM);

	bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL);
	kfree(devname);
	return bdev;
}

static int
bl_parse_scsi(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];
	struct block_device *bdev;
	const struct pr_ops *ops;
	int error;

	if (!bl_validate_designator(v))
		return -EINVAL;

	bdev = bl_open_dm_mpath_udev_path(v);
	if (IS_ERR(bdev))
		bdev = bl_open_udev_path(v);
	if (IS_ERR(bdev))
		return PTR_ERR(bdev);
	d->bdev = bdev;

	d->len = i_size_read(d->bdev->bd_inode);
	d->map = bl_map_simple;
	d->pr_key = v->scsi.pr_key;

	pr_info("pNFS: using block device %s (reservation key 0x%llx)\n",
		d->bdev->bd_disk->disk_name, d->pr_key);

	ops = d->bdev->bd_disk->fops->pr_ops;
	if (!ops) {
		pr_err("pNFS: block device %s does not support reservations.",
				d->bdev->bd_disk->disk_name);
		error = -EINVAL;
		goto out_blkdev_put;
	}

	error = ops->pr_register(d->bdev, 0, d->pr_key, true);
	if (error) {
		pr_err("pNFS: failed to register key for block device %s.",
				d->bdev->bd_disk->disk_name);
		goto out_blkdev_put;
	}

	d->pr_registered = true;
	return 0;

out_blkdev_put:
	blkdev_put(d->bdev, FMODE_READ | FMODE_WRITE);
	return error;
}

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);
	case PNFS_BLOCK_VOLUME_SCSI:
		return bl_parse_scsi(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;
}
Commit	Line	Data
5c83746a	1	/*
d9186c03	2	* Copyright (c) 2014-2016 Christoph Hellwig.
5c83746a CH	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>
d9186c03	9	#include <linux/pr.h>
5c83746a CH	10
	11	#include "blocklayout.h"
	12
	13	#define NFSDBG_FACILITY NFSDBG_PNFS_LD
	14
	15	static void
	16	bl_free_device(struct pnfs_block_dev *dev)
	17	{
	18	if (dev->nr_children) {
	19	int i;
	20
	21	for (i = 0; i < dev->nr_children; i++)
	22	bl_free_device(&dev->children[i]);
	23	kfree(dev->children);
	24	} else {
d9186c03 CH	25	if (dev->pr_registered) {
	26	const struct pr_ops *ops =
	27	dev->bdev->bd_disk->fops->pr_ops;
	28	int error;
	29
	30	error = ops->pr_register(dev->bdev, dev->pr_key, 0,
	31	false);
	32	if (error)
	33	pr_err("failed to unregister PR key.\n");
	34	}
	35
5c83746a	36	if (dev->bdev)
513d6d7a	37	blkdev_put(dev->bdev, FMODE_READ \| FMODE_WRITE);
5c83746a CH	38	}
	39	}
	40
	41	void
	42	bl_free_deviceid_node(struct nfs4_deviceid_node *d)
	43	{
	44	struct pnfs_block_dev *dev =
	45	container_of(d, struct pnfs_block_dev, node);
	46
	47	bl_free_device(dev);
84a80f62	48	kfree_rcu(dev, node.rcu);
5c83746a CH	49	}
	50
	51	static int
	52	nfs4_block_decode_volume(struct xdr_stream xdr, struct pnfs_block_volume b)
	53	{
	54	__be32 *p;
	55	int i;
	56
	57	p = xdr_inline_decode(xdr, 4);
	58	if (!p)
	59	return -EIO;
	60	b->type = be32_to_cpup(p++);
	61
	62	switch (b->type) {
	63	case PNFS_BLOCK_VOLUME_SIMPLE:
	64	p = xdr_inline_decode(xdr, 4);
	65	if (!p)
	66	return -EIO;
	67	b->simple.nr_sigs = be32_to_cpup(p++);
c77efc1e KM	68	if (!b->simple.nr_sigs \|\| b->simple.nr_sigs > PNFS_BLOCK_MAX_UUIDS) {
c77efc1e KM	69	dprintk("Bad signature count: %d\n", b->simple.nr_sigs);
5c83746a CH	70	return -EIO;
	71	}
	72
	73	b->simple.len = 4 + 4;
	74	for (i = 0; i < b->simple.nr_sigs; i++) {
	75	p = xdr_inline_decode(xdr, 8 + 4);
	76	if (!p)
	77	return -EIO;
	78	p = xdr_decode_hyper(p, &b->simple.sigs[i].offset);
	79	b->simple.sigs[i].sig_len = be32_to_cpup(p++);
2bd3c63a CH	80	if (b->simple.sigs[i].sig_len > PNFS_BLOCK_UUID_LEN) {
	81	pr_info("signature too long: %d\n",
	82	b->simple.sigs[i].sig_len);
	83	return -EIO;
	84	}
5c83746a CH	85
	86	p = xdr_inline_decode(xdr, b->simple.sigs[i].sig_len);
	87	if (!p)
	88	return -EIO;
	89	memcpy(&b->simple.sigs[i].sig, p,
	90	b->simple.sigs[i].sig_len);
	91
ecc2b88c KM	92	b->simple.len += 8 + 4 + \
ecc2b88c KM	93	(XDR_QUADLEN(b->simple.sigs[i].sig_len) << 2);
5c83746a CH	94	}
	95	break;
	96	case PNFS_BLOCK_VOLUME_SLICE:
	97	p = xdr_inline_decode(xdr, 8 + 8 + 4);
	98	if (!p)
	99	return -EIO;
	100	p = xdr_decode_hyper(p, &b->slice.start);
	101	p = xdr_decode_hyper(p, &b->slice.len);
	102	b->slice.volume = be32_to_cpup(p++);
	103	break;
	104	case PNFS_BLOCK_VOLUME_CONCAT:
	105	p = xdr_inline_decode(xdr, 4);
	106	if (!p)
	107	return -EIO;
c77efc1e	108
5c83746a	109	b->concat.volumes_count = be32_to_cpup(p++);
c77efc1e KM	110	if (b->concat.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
	111	dprintk("Too many volumes: %d\n", b->concat.volumes_count);
	112	return -EIO;
	113	}
5c83746a CH	114
	115	p = xdr_inline_decode(xdr, b->concat.volumes_count * 4);
	116	if (!p)
	117	return -EIO;
	118	for (i = 0; i < b->concat.volumes_count; i++)
	119	b->concat.volumes[i] = be32_to_cpup(p++);
	120	break;
	121	case PNFS_BLOCK_VOLUME_STRIPE:
	122	p = xdr_inline_decode(xdr, 8 + 4);
	123	if (!p)
	124	return -EIO;
c77efc1e	125
5c83746a CH	126	p = xdr_decode_hyper(p, &b->stripe.chunk_size);
5c83746a CH	127	b->stripe.volumes_count = be32_to_cpup(p++);
c77efc1e KM	128	if (b->stripe.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
	129	dprintk("Too many volumes: %d\n", b->stripe.volumes_count);
	130	return -EIO;
	131	}
5c83746a CH	132
	133	p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4);
	134	if (!p)
	135	return -EIO;
	136	for (i = 0; i < b->stripe.volumes_count; i++)
	137	b->stripe.volumes[i] = be32_to_cpup(p++);
	138	break;
d9186c03 CH	139	case PNFS_BLOCK_VOLUME_SCSI:
	140	p = xdr_inline_decode(xdr, 4 + 4 + 4);
	141	if (!p)
	142	return -EIO;
	143	b->scsi.code_set = be32_to_cpup(p++);
	144	b->scsi.designator_type = be32_to_cpup(p++);
	145	b->scsi.designator_len = be32_to_cpup(p++);
	146	p = xdr_inline_decode(xdr, b->scsi.designator_len);
	147	if (!p)
	148	return -EIO;
	149	if (b->scsi.designator_len > 256)
	150	return -EIO;
	151	memcpy(&b->scsi.designator, p, b->scsi.designator_len);
	152	p = xdr_inline_decode(xdr, 8);
	153	if (!p)
	154	return -EIO;
	155	p = xdr_decode_hyper(p, &b->scsi.pr_key);
	156	break;
5c83746a CH	157	default:
	158	dprintk("unknown volume type!\n");
	159	return -EIO;
	160	}
	161
	162	return 0;
	163	}
	164
	165	static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset,
	166	struct pnfs_block_dev_map *map)
	167	{
	168	map->start = dev->start;
	169	map->len = dev->len;
	170	map->disk_offset = dev->disk_offset;
	171	map->bdev = dev->bdev;
	172	return true;
	173	}
	174
	175	static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset,
	176	struct pnfs_block_dev_map *map)
	177	{
	178	int i;
	179
	180	for (i = 0; i < dev->nr_children; i++) {
	181	struct pnfs_block_dev *child = &dev->children[i];
	182
	183	if (child->start > offset \|\|
	184	child->start + child->len <= offset)
	185	continue;
	186
	187	child->map(child, offset - child->start, map);
	188	return true;
	189	}
	190
	191	dprintk("%s: ran off loop!\n", __func__);
	192	return false;
	193	}
	194
	195	static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset,
	196	struct pnfs_block_dev_map *map)
	197	{
	198	struct pnfs_block_dev *child;
5466112f TM	199	u64 chunk;
5466112f TM	200	u32 chunk_idx;
5c83746a CH	201	u64 disk_offset;
5c83746a CH	202
5466112f TM	203	chunk = div_u64(offset, dev->chunk_size);
	204	div_u64_rem(chunk, dev->nr_children, &chunk_idx);
	205
5c83746a CH	206	if (chunk_idx > dev->nr_children) {
	207	dprintk("%s: invalid chunk idx %d (%lld/%lld)\n",
	208	__func__, chunk_idx, offset, dev->chunk_size);
	209	/* error, should not happen */
	210	return false;
	211	}
	212
	213	/* truncate offset to the beginning of the stripe */
	214	offset = chunk * dev->chunk_size;
	215
	216	/* disk offset of the stripe */
5466112f	217	disk_offset = div_u64(offset, dev->nr_children);
5c83746a CH	218
	219	child = &dev->children[chunk_idx];
	220	child->map(child, disk_offset, map);
	221
	222	map->start += offset;
	223	map->disk_offset += disk_offset;
	224	map->len = dev->chunk_size;
	225	return true;
	226	}
	227
	228	static int
	229	bl_parse_deviceid(struct nfs_server server, struct pnfs_block_dev d,
	230	struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask);
	231
	232
	233	static int
	234	bl_parse_simple(struct nfs_server server, struct pnfs_block_dev d,
	235	struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
	236	{
	237	struct pnfs_block_volume *v = &volumes[idx];
297fae4d	238	struct block_device *bdev;
5c83746a CH	239	dev_t dev;
	240
	241	dev = bl_resolve_deviceid(server, v, gfp_mask);
	242	if (!dev)
	243	return -EIO;
	244
297fae4d AS	245	bdev = blkdev_get_by_dev(dev, FMODE_READ \| FMODE_WRITE, NULL);
297fae4d AS	246	if (IS_ERR(bdev)) {
5c83746a	247	printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
297fae4d AS	248	MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
297fae4d AS	249	return PTR_ERR(bdev);
5c83746a	250	}
297fae4d	251	d->bdev = bdev;
5c83746a CH	252
	253
	254	d->len = i_size_read(d->bdev->bd_inode);
	255	d->map = bl_map_simple;
	256
	257	printk(KERN_INFO "pNFS: using block device %s\n",
	258	d->bdev->bd_disk->disk_name);
	259	return 0;
	260	}
	261
d9186c03 CH	262	static bool
	263	bl_validate_designator(struct pnfs_block_volume *v)
	264	{
	265	switch (v->scsi.designator_type) {
	266	case PS_DESIGNATOR_EUI64:
	267	if (v->scsi.code_set != PS_CODE_SET_BINARY)
	268	return false;
	269
	270	if (v->scsi.designator_len != 8 &&
	271	v->scsi.designator_len != 10 &&
	272	v->scsi.designator_len != 16)
	273	return false;
	274
	275	return true;
	276	case PS_DESIGNATOR_NAA:
	277	if (v->scsi.code_set != PS_CODE_SET_BINARY)
	278	return false;
	279
	280	if (v->scsi.designator_len != 8 &&
	281	v->scsi.designator_len != 16)
	282	return false;
	283
	284	return true;
	285	case PS_DESIGNATOR_T10:
	286	case PS_DESIGNATOR_NAME:
	287	pr_err("pNFS: unsupported designator "
	288	"(code set %d, type %d, len %d.\n",
	289	v->scsi.code_set,
	290	v->scsi.designator_type,
	291	v->scsi.designator_len);
	292	return false;
	293	default:
	294	pr_err("pNFS: invalid designator "
	295	"(code set %d, type %d, len %d.\n",
	296	v->scsi.code_set,
	297	v->scsi.designator_type,
	298	v->scsi.designator_len);
	299	return false;
	300	}
	301	}
	302
d702d41e CH	303	/*
	304	* Try to open the udev path for the WWN. At least on Debian the udev
	305	* by-id path will always point to the dm-multipath device if one exists.
	306	*/
	307	static struct block_device *
	308	bl_open_udev_path(struct pnfs_block_volume *v)
	309	{
	310	struct block_device *bdev;
	311	const char *devname;
	312
	313	devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%*phN",
	314	v->scsi.designator_len, v->scsi.designator);
	315	if (!devname)
	316	return ERR_PTR(-ENOMEM);
	317
	318	bdev = blkdev_get_by_path(devname, FMODE_READ \| FMODE_WRITE, NULL);
	319	if (IS_ERR(bdev)) {
	320	pr_warn("pNFS: failed to open device %s (%ld)\n",
	321	devname, PTR_ERR(bdev));
	322	}
	323
	324	kfree(devname);
	325	return bdev;
	326	}
	327
11487ddb CH	328	/*
	329	* Try to open the RH/Fedora specific dm-mpath udev path for this WWN, as the
	330	* wwn- links will only point to the first discovered SCSI device there.
	331	*/
	332	static struct block_device *
	333	bl_open_dm_mpath_udev_path(struct pnfs_block_volume *v)
	334	{
	335	struct block_device *bdev;
	336	const char *devname;
	337
	338	devname = kasprintf(GFP_KERNEL,
	339	"/dev/disk/by-id/dm-uuid-mpath-%d%*phN",
	340	v->scsi.designator_type,
	341	v->scsi.designator_len, v->scsi.designator);
	342	if (!devname)
	343	return ERR_PTR(-ENOMEM);
	344
	345	bdev = blkdev_get_by_path(devname, FMODE_READ \| FMODE_WRITE, NULL);
	346	kfree(devname);
	347	return bdev;
	348	}
	349
d9186c03 CH	350	static int
	351	bl_parse_scsi(struct nfs_server server, struct pnfs_block_dev d,
	352	struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
	353	{
	354	struct pnfs_block_volume *v = &volumes[idx];
297fae4d	355	struct block_device *bdev;
d9186c03	356	const struct pr_ops *ops;
d9186c03 CH	357	int error;
	358
	359	if (!bl_validate_designator(v))
	360	return -EINVAL;
	361
297fae4d AS	362	bdev = bl_open_dm_mpath_udev_path(v);
	363	if (IS_ERR(bdev))
	364	bdev = bl_open_udev_path(v);
	365	if (IS_ERR(bdev))
	366	return PTR_ERR(bdev);
	367	d->bdev = bdev;
d9186c03 CH	368
	369	d->len = i_size_read(d->bdev->bd_inode);
	370	d->map = bl_map_simple;
	371	d->pr_key = v->scsi.pr_key;
	372
	373	pr_info("pNFS: using block device %s (reservation key 0x%llx)\n",
	374	d->bdev->bd_disk->disk_name, d->pr_key);
	375
	376	ops = d->bdev->bd_disk->fops->pr_ops;
	377	if (!ops) {
	378	pr_err("pNFS: block device %s does not support reservations.",
	379	d->bdev->bd_disk->disk_name);
	380	error = -EINVAL;
	381	goto out_blkdev_put;
	382	}
	383
	384	error = ops->pr_register(d->bdev, 0, d->pr_key, true);
	385	if (error) {
	386	pr_err("pNFS: failed to register key for block device %s.",
	387	d->bdev->bd_disk->disk_name);
	388	goto out_blkdev_put;
	389	}
	390
	391	d->pr_registered = true;
	392	return 0;
	393
	394	out_blkdev_put:
0173ca05	395	blkdev_put(d->bdev, FMODE_READ \| FMODE_WRITE);
d9186c03 CH	396	return error;
	397	}
	398
5c83746a CH	399	static int
	400	bl_parse_slice(struct nfs_server server, struct pnfs_block_dev d,
	401	struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
	402	{
	403	struct pnfs_block_volume *v = &volumes[idx];
	404	int ret;
	405
	406	ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask);
	407	if (ret)
	408	return ret;
	409
	410	d->disk_offset = v->slice.start;
	411	d->len = v->slice.len;
	412	return 0;
	413	}
	414
	415	static int
	416	bl_parse_concat(struct nfs_server server, struct pnfs_block_dev d,
	417	struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
	418	{
	419	struct pnfs_block_volume *v = &volumes[idx];
	420	u64 len = 0;
	421	int ret, i;
	422
	423	d->children = kcalloc(v->concat.volumes_count,
	424	sizeof(struct pnfs_block_dev), GFP_KERNEL);
	425	if (!d->children)
	426	return -ENOMEM;
	427
	428	for (i = 0; i < v->concat.volumes_count; i++) {
	429	ret = bl_parse_deviceid(server, &d->children[i],
	430	volumes, v->concat.volumes[i], gfp_mask);
	431	if (ret)
	432	return ret;
	433
	434	d->nr_children++;
	435	d->children[i].start += len;
	436	len += d->children[i].len;
	437	}
	438
	439	d->len = len;
	440	d->map = bl_map_concat;
	441	return 0;
	442	}
	443
	444	static int
	445	bl_parse_stripe(struct nfs_server server, struct pnfs_block_dev d,
	446	struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
	447	{
	448	struct pnfs_block_volume *v = &volumes[idx];
	449	u64 len = 0;
	450	int ret, i;
	451
	452	d->children = kcalloc(v->stripe.volumes_count,
	453	sizeof(struct pnfs_block_dev), GFP_KERNEL);
	454	if (!d->children)
	455	return -ENOMEM;
	456
	457	for (i = 0; i < v->stripe.volumes_count; i++) {
	458	ret = bl_parse_deviceid(server, &d->children[i],
	459	volumes, v->stripe.volumes[i], gfp_mask);
	460	if (ret)
	461	return ret;
	462
463	d->nr_children++;
464	len += d->children[i].len;
465	}
466
467	d->len = len;
468	d->chunk_size = v->stripe.chunk_size;
469	d->map = bl_map_stripe;
470	return 0;
471	}
472
473	static int
474	bl_parse_deviceid(struct nfs_server server, struct pnfs_block_dev d,
475	struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
476	{
477	switch (volumes[idx].type) {
478	case PNFS_BLOCK_VOLUME_SIMPLE:
479	return bl_parse_simple(server, d, volumes, idx, gfp_mask);
480	case PNFS_BLOCK_VOLUME_SLICE:
481	return bl_parse_slice(server, d, volumes, idx, gfp_mask);
482	case PNFS_BLOCK_VOLUME_CONCAT:
483	return bl_parse_concat(server, d, volumes, idx, gfp_mask);
484	case PNFS_BLOCK_VOLUME_STRIPE:
485	return bl_parse_stripe(server, d, volumes, idx, gfp_mask);
d9186c03 CH	486	case PNFS_BLOCK_VOLUME_SCSI:
d9186c03 CH	487	return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
5c83746a CH	488	default:
	489	dprintk("unsupported volume type: %d\n", volumes[idx].type);
	490	return -EIO;
	491	}
	492	}
	493
	494	struct nfs4_deviceid_node *
	495	bl_alloc_deviceid_node(struct nfs_server server, struct pnfs_device pdev,
	496	gfp_t gfp_mask)
	497	{
	498	struct nfs4_deviceid_node *node = NULL;
	499	struct pnfs_block_volume *volumes;
	500	struct pnfs_block_dev *top;
	501	struct xdr_stream xdr;
	502	struct xdr_buf buf;
	503	struct page *scratch;
	504	int nr_volumes, ret, i;
	505	__be32 *p;
	506
	507	scratch = alloc_page(gfp_mask);
	508	if (!scratch)
	509	goto out;
	510
	511	xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
	512	xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE);
	513
	514	p = xdr_inline_decode(&xdr, sizeof(__be32));
	515	if (!p)
	516	goto out_free_scratch;
	517	nr_volumes = be32_to_cpup(p++);
	518
	519	volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume),
	520	gfp_mask);
	521	if (!volumes)
	522	goto out_free_scratch;
	523
	524	for (i = 0; i < nr_volumes; i++) {
	525	ret = nfs4_block_decode_volume(&xdr, &volumes[i]);
	526	if (ret < 0)
	527	goto out_free_volumes;
	528	}
	529
	530	top = kzalloc(sizeof(*top), gfp_mask);
	531	if (!top)
	532	goto out_free_volumes;
	533
	534	ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask);
	535	if (ret) {
	536	bl_free_device(top);
	537	kfree(top);
	538	goto out_free_volumes;
	539	}
	540
	541	node = &top->node;
	542	nfs4_init_deviceid_node(node, server, &pdev->dev_id);
	543
	544	out_free_volumes:
	545	kfree(volumes);
	546	out_free_scratch:
	547	__free_page(scratch);
	548	out:
	549	return node;
	550	}