linux/fs/nfsd/blocklayout.c
Christoph Hellwig f99d4fbdae nfsd: add SCSI layout support
This is a simple extension to the block layout driver to use SCSI
persistent reservations for access control and fencing, as well as
SCSI VPD pages for device identification.

For this we need to pass the nfs4_client to the proc_getdeviceinfo method
to generate the reservation key, and add a new fence_client method
to allow for fence actions in the layout driver.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-03-18 11:42:53 -04:00

409 lines
10 KiB
C

/*
* Copyright (c) 2014-2016 Christoph Hellwig.
*/
#include <linux/exportfs.h>
#include <linux/genhd.h>
#include <linux/slab.h>
#include <linux/pr.h>
#include <linux/nfsd/debug.h>
#include <scsi/scsi_proto.h>
#include <scsi/scsi_common.h>
#include "blocklayoutxdr.h"
#include "pnfs.h"
#define NFSDDBG_FACILITY NFSDDBG_PNFS
static __be32
nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
struct nfsd4_layoutget *args)
{
struct nfsd4_layout_seg *seg = &args->lg_seg;
struct super_block *sb = inode->i_sb;
u32 block_size = (1 << inode->i_blkbits);
struct pnfs_block_extent *bex;
struct iomap iomap;
u32 device_generation = 0;
int error;
if (seg->offset & (block_size - 1)) {
dprintk("pnfsd: I/O misaligned\n");
goto out_layoutunavailable;
}
/*
* Some clients barf on non-zero block numbers for NONE or INVALID
* layouts, so make sure to zero the whole structure.
*/
error = -ENOMEM;
bex = kzalloc(sizeof(*bex), GFP_KERNEL);
if (!bex)
goto out_error;
args->lg_content = bex;
error = sb->s_export_op->map_blocks(inode, seg->offset, seg->length,
&iomap, seg->iomode != IOMODE_READ,
&device_generation);
if (error) {
if (error == -ENXIO)
goto out_layoutunavailable;
goto out_error;
}
if (iomap.length < args->lg_minlength) {
dprintk("pnfsd: extent smaller than minlength\n");
goto out_layoutunavailable;
}
switch (iomap.type) {
case IOMAP_MAPPED:
if (seg->iomode == IOMODE_READ)
bex->es = PNFS_BLOCK_READ_DATA;
else
bex->es = PNFS_BLOCK_READWRITE_DATA;
bex->soff = (iomap.blkno << 9);
break;
case IOMAP_UNWRITTEN:
if (seg->iomode & IOMODE_RW) {
/*
* Crack monkey special case from section 2.3.1.
*/
if (args->lg_minlength == 0) {
dprintk("pnfsd: no soup for you!\n");
goto out_layoutunavailable;
}
bex->es = PNFS_BLOCK_INVALID_DATA;
bex->soff = (iomap.blkno << 9);
break;
}
/*FALLTHRU*/
case IOMAP_HOLE:
if (seg->iomode == IOMODE_READ) {
bex->es = PNFS_BLOCK_NONE_DATA;
break;
}
/*FALLTHRU*/
case IOMAP_DELALLOC:
default:
WARN(1, "pnfsd: filesystem returned %d extent\n", iomap.type);
goto out_layoutunavailable;
}
error = nfsd4_set_deviceid(&bex->vol_id, fhp, device_generation);
if (error)
goto out_error;
bex->foff = iomap.offset;
bex->len = iomap.length;
seg->offset = iomap.offset;
seg->length = iomap.length;
dprintk("GET: 0x%llx:0x%llx %d\n", bex->foff, bex->len, bex->es);
return 0;
out_error:
seg->length = 0;
return nfserrno(error);
out_layoutunavailable:
seg->length = 0;
return nfserr_layoutunavailable;
}
static __be32
nfsd4_block_commit_blocks(struct inode *inode, struct nfsd4_layoutcommit *lcp,
struct iomap *iomaps, int nr_iomaps)
{
loff_t new_size = lcp->lc_last_wr + 1;
struct iattr iattr = { .ia_valid = 0 };
int error;
if (lcp->lc_mtime.tv_nsec == UTIME_NOW ||
timespec_compare(&lcp->lc_mtime, &inode->i_mtime) < 0)
lcp->lc_mtime = current_fs_time(inode->i_sb);
iattr.ia_valid |= ATTR_ATIME | ATTR_CTIME | ATTR_MTIME;
iattr.ia_atime = iattr.ia_ctime = iattr.ia_mtime = lcp->lc_mtime;
if (new_size > i_size_read(inode)) {
iattr.ia_valid |= ATTR_SIZE;
iattr.ia_size = new_size;
}
error = inode->i_sb->s_export_op->commit_blocks(inode, iomaps,
nr_iomaps, &iattr);
kfree(iomaps);
return nfserrno(error);
}
#ifdef CONFIG_NFSD_BLOCKLAYOUT
static int
nfsd4_block_get_device_info_simple(struct super_block *sb,
struct nfsd4_getdeviceinfo *gdp)
{
struct pnfs_block_deviceaddr *dev;
struct pnfs_block_volume *b;
dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
sizeof(struct pnfs_block_volume), GFP_KERNEL);
if (!dev)
return -ENOMEM;
gdp->gd_device = dev;
dev->nr_volumes = 1;
b = &dev->volumes[0];
b->type = PNFS_BLOCK_VOLUME_SIMPLE;
b->simple.sig_len = PNFS_BLOCK_UUID_LEN;
return sb->s_export_op->get_uuid(sb, b->simple.sig, &b->simple.sig_len,
&b->simple.offset);
}
static __be32
nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
struct nfs4_client *clp,
struct nfsd4_getdeviceinfo *gdp)
{
if (sb->s_bdev != sb->s_bdev->bd_contains)
return nfserr_inval;
return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
}
static __be32
nfsd4_block_proc_layoutcommit(struct inode *inode,
struct nfsd4_layoutcommit *lcp)
{
struct iomap *iomaps;
int nr_iomaps;
nr_iomaps = nfsd4_block_decode_layoutupdate(lcp->lc_up_layout,
lcp->lc_up_len, &iomaps, 1 << inode->i_blkbits);
if (nr_iomaps < 0)
return nfserrno(nr_iomaps);
return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
}
const struct nfsd4_layout_ops bl_layout_ops = {
/*
* Pretend that we send notification to the client. This is a blatant
* lie to force recent Linux clients to cache our device IDs.
* We rarely ever change the device ID, so the harm of leaking deviceids
* for a while isn't too bad. Unfortunately RFC5661 is a complete mess
* in this regard, but I filed errata 4119 for this a while ago, and
* hopefully the Linux client will eventually start caching deviceids
* without this again.
*/
.notify_types =
NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
.proc_getdeviceinfo = nfsd4_block_proc_getdeviceinfo,
.encode_getdeviceinfo = nfsd4_block_encode_getdeviceinfo,
.proc_layoutget = nfsd4_block_proc_layoutget,
.encode_layoutget = nfsd4_block_encode_layoutget,
.proc_layoutcommit = nfsd4_block_proc_layoutcommit,
};
#endif /* CONFIG_NFSD_BLOCKLAYOUT */
#ifdef CONFIG_NFSD_SCSILAYOUT
static int nfsd4_scsi_identify_device(struct block_device *bdev,
struct pnfs_block_volume *b)
{
struct request_queue *q = bdev->bd_disk->queue;
struct request *rq;
size_t bufflen = 252, len, id_len;
u8 *buf, *d, type, assoc;
int error;
buf = kzalloc(bufflen, GFP_KERNEL);
if (!buf)
return -ENOMEM;
rq = blk_get_request(q, READ, GFP_KERNEL);
if (IS_ERR(rq)) {
error = -ENOMEM;
goto out_free_buf;
}
blk_rq_set_block_pc(rq);
error = blk_rq_map_kern(q, rq, buf, bufflen, GFP_KERNEL);
if (error)
goto out_put_request;
rq->cmd[0] = INQUIRY;
rq->cmd[1] = 1;
rq->cmd[2] = 0x83;
rq->cmd[3] = bufflen >> 8;
rq->cmd[4] = bufflen & 0xff;
rq->cmd_len = COMMAND_SIZE(INQUIRY);
error = blk_execute_rq(rq->q, NULL, rq, 1);
if (error) {
pr_err("pNFS: INQUIRY 0x83 failed with: %x\n",
rq->errors);
goto out_put_request;
}
len = (buf[2] << 8) + buf[3] + 4;
if (len > bufflen) {
pr_err("pNFS: INQUIRY 0x83 response invalid (len = %zd)\n",
len);
goto out_put_request;
}
d = buf + 4;
for (d = buf + 4; d < buf + len; d += id_len + 4) {
id_len = d[3];
type = d[1] & 0xf;
assoc = (d[1] >> 4) & 0x3;
/*
* We only care about a EUI-64 and NAA designator types
* with LU association.
*/
if (assoc != 0x00)
continue;
if (type != 0x02 && type != 0x03)
continue;
if (id_len != 8 && id_len != 12 && id_len != 16)
continue;
b->scsi.code_set = PS_CODE_SET_BINARY;
b->scsi.designator_type = type == 0x02 ?
PS_DESIGNATOR_EUI64 : PS_DESIGNATOR_NAA;
b->scsi.designator_len = id_len;
memcpy(b->scsi.designator, d + 4, id_len);
/*
* If we found a 8 or 12 byte descriptor continue on to
* see if a 16 byte one is available. If we find a
* 16 byte descriptor we're done.
*/
if (id_len == 16)
break;
}
out_put_request:
blk_put_request(rq);
out_free_buf:
kfree(buf);
return error;
}
#define NFSD_MDS_PR_KEY 0x0100000000000000
/*
* We use the client ID as a unique key for the reservations.
* This allows us to easily fence a client when recalls fail.
*/
static u64 nfsd4_scsi_pr_key(struct nfs4_client *clp)
{
return ((u64)clp->cl_clientid.cl_boot << 32) | clp->cl_clientid.cl_id;
}
static int
nfsd4_block_get_device_info_scsi(struct super_block *sb,
struct nfs4_client *clp,
struct nfsd4_getdeviceinfo *gdp)
{
struct pnfs_block_deviceaddr *dev;
struct pnfs_block_volume *b;
const struct pr_ops *ops;
int error;
dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
sizeof(struct pnfs_block_volume), GFP_KERNEL);
if (!dev)
return -ENOMEM;
gdp->gd_device = dev;
dev->nr_volumes = 1;
b = &dev->volumes[0];
b->type = PNFS_BLOCK_VOLUME_SCSI;
b->scsi.pr_key = nfsd4_scsi_pr_key(clp);
error = nfsd4_scsi_identify_device(sb->s_bdev, b);
if (error)
return error;
ops = sb->s_bdev->bd_disk->fops->pr_ops;
if (!ops) {
pr_err("pNFS: device %s does not support PRs.\n",
sb->s_id);
return -EINVAL;
}
error = ops->pr_register(sb->s_bdev, 0, NFSD_MDS_PR_KEY, true);
if (error) {
pr_err("pNFS: failed to register key for device %s.\n",
sb->s_id);
return -EINVAL;
}
error = ops->pr_reserve(sb->s_bdev, NFSD_MDS_PR_KEY,
PR_EXCLUSIVE_ACCESS_REG_ONLY, 0);
if (error) {
pr_err("pNFS: failed to reserve device %s.\n",
sb->s_id);
return -EINVAL;
}
return 0;
}
static __be32
nfsd4_scsi_proc_getdeviceinfo(struct super_block *sb,
struct nfs4_client *clp,
struct nfsd4_getdeviceinfo *gdp)
{
if (sb->s_bdev != sb->s_bdev->bd_contains)
return nfserr_inval;
return nfserrno(nfsd4_block_get_device_info_scsi(sb, clp, gdp));
}
static __be32
nfsd4_scsi_proc_layoutcommit(struct inode *inode,
struct nfsd4_layoutcommit *lcp)
{
struct iomap *iomaps;
int nr_iomaps;
nr_iomaps = nfsd4_scsi_decode_layoutupdate(lcp->lc_up_layout,
lcp->lc_up_len, &iomaps, 1 << inode->i_blkbits);
if (nr_iomaps < 0)
return nfserrno(nr_iomaps);
return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
}
static void
nfsd4_scsi_fence_client(struct nfs4_layout_stateid *ls)
{
struct nfs4_client *clp = ls->ls_stid.sc_client;
struct block_device *bdev = ls->ls_file->f_path.mnt->mnt_sb->s_bdev;
bdev->bd_disk->fops->pr_ops->pr_preempt(bdev, NFSD_MDS_PR_KEY,
nfsd4_scsi_pr_key(clp), 0, true);
}
const struct nfsd4_layout_ops scsi_layout_ops = {
/*
* Pretend that we send notification to the client. This is a blatant
* lie to force recent Linux clients to cache our device IDs.
* We rarely ever change the device ID, so the harm of leaking deviceids
* for a while isn't too bad. Unfortunately RFC5661 is a complete mess
* in this regard, but I filed errata 4119 for this a while ago, and
* hopefully the Linux client will eventually start caching deviceids
* without this again.
*/
.notify_types =
NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
.proc_getdeviceinfo = nfsd4_scsi_proc_getdeviceinfo,
.encode_getdeviceinfo = nfsd4_block_encode_getdeviceinfo,
.proc_layoutget = nfsd4_block_proc_layoutget,
.encode_layoutget = nfsd4_block_encode_layoutget,
.proc_layoutcommit = nfsd4_scsi_proc_layoutcommit,
.fence_client = nfsd4_scsi_fence_client,
};
#endif /* CONFIG_NFSD_SCSILAYOUT */