https://github.com/torvalds/linux
Tip revision: 92e963f50fc74041b5e9e744c330dca48e04f08d authored by Linus Torvalds on 24 January 2016, 21:06:47 UTC
Linux 4.5-rc1
Linux 4.5-rc1
Tip revision: 92e963f
filelayoutdev.c
/*
* Device operations for the pnfs nfs4 file layout driver.
*
* Copyright (c) 2002
* The Regents of the University of Michigan
* All Rights Reserved
*
* Dean Hildebrand <dhildebz@umich.edu>
* Garth Goodson <Garth.Goodson@netapp.com>
*
* Permission is granted to use, copy, create derivative works, and
* redistribute this software and such derivative works for any purpose,
* so long as the name of the University of Michigan is not used in
* any advertising or publicity pertaining to the use or distribution
* of this software without specific, written prior authorization. If
* the above copyright notice or any other identification of the
* University of Michigan is included in any copy of any portion of
* this software, then the disclaimer below must also be included.
*
* This software is provided as is, without representation or warranty
* of any kind either express or implied, including without limitation
* the implied warranties of merchantability, fitness for a particular
* purpose, or noninfringement. The Regents of the University of
* Michigan shall not be liable for any damages, including special,
* indirect, incidental, or consequential damages, with respect to any
* claim arising out of or in connection with the use of the software,
* even if it has been or is hereafter advised of the possibility of
* such damages.
*/
#include <linux/nfs_fs.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
#include "../internal.h"
#include "../nfs4session.h"
#include "filelayout.h"
#define NFSDBG_FACILITY NFSDBG_PNFS_LD
static unsigned int dataserver_timeo = NFS4_DEF_DS_TIMEO;
static unsigned int dataserver_retrans = NFS4_DEF_DS_RETRANS;
void
nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
{
struct nfs4_pnfs_ds *ds;
int i;
nfs4_print_deviceid(&dsaddr->id_node.deviceid);
for (i = 0; i < dsaddr->ds_num; i++) {
ds = dsaddr->ds_list[i];
if (ds != NULL)
nfs4_pnfs_ds_put(ds);
}
kfree(dsaddr->stripe_indices);
kfree_rcu(dsaddr, id_node.rcu);
}
/* Decode opaque device data and return the result */
struct nfs4_file_layout_dsaddr *
nfs4_fl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
gfp_t gfp_flags)
{
int i;
u32 cnt, num;
u8 *indexp;
__be32 *p;
u8 *stripe_indices;
u8 max_stripe_index;
struct nfs4_file_layout_dsaddr *dsaddr = NULL;
struct xdr_stream stream;
struct xdr_buf buf;
struct page *scratch;
struct list_head dsaddrs;
struct nfs4_pnfs_ds_addr *da;
/* set up xdr stream */
scratch = alloc_page(gfp_flags);
if (!scratch)
goto out_err;
xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
/* Get the stripe count (number of stripe index) */
p = xdr_inline_decode(&stream, 4);
if (unlikely(!p))
goto out_err_free_scratch;
cnt = be32_to_cpup(p);
dprintk("%s stripe count %d\n", __func__, cnt);
if (cnt > NFS4_PNFS_MAX_STRIPE_CNT) {
printk(KERN_WARNING "NFS: %s: stripe count %d greater than "
"supported maximum %d\n", __func__,
cnt, NFS4_PNFS_MAX_STRIPE_CNT);
goto out_err_free_scratch;
}
/* read stripe indices */
stripe_indices = kcalloc(cnt, sizeof(u8), gfp_flags);
if (!stripe_indices)
goto out_err_free_scratch;
p = xdr_inline_decode(&stream, cnt << 2);
if (unlikely(!p))
goto out_err_free_stripe_indices;
indexp = &stripe_indices[0];
max_stripe_index = 0;
for (i = 0; i < cnt; i++) {
*indexp = be32_to_cpup(p++);
max_stripe_index = max(max_stripe_index, *indexp);
indexp++;
}
/* Check the multipath list count */
p = xdr_inline_decode(&stream, 4);
if (unlikely(!p))
goto out_err_free_stripe_indices;
num = be32_to_cpup(p);
dprintk("%s ds_num %u\n", __func__, num);
if (num > NFS4_PNFS_MAX_MULTI_CNT) {
printk(KERN_WARNING "NFS: %s: multipath count %d greater than "
"supported maximum %d\n", __func__,
num, NFS4_PNFS_MAX_MULTI_CNT);
goto out_err_free_stripe_indices;
}
/* validate stripe indices are all < num */
if (max_stripe_index >= num) {
printk(KERN_WARNING "NFS: %s: stripe index %u >= num ds %u\n",
__func__, max_stripe_index, num);
goto out_err_free_stripe_indices;
}
dsaddr = kzalloc(sizeof(*dsaddr) +
(sizeof(struct nfs4_pnfs_ds *) * (num - 1)),
gfp_flags);
if (!dsaddr)
goto out_err_free_stripe_indices;
dsaddr->stripe_count = cnt;
dsaddr->stripe_indices = stripe_indices;
stripe_indices = NULL;
dsaddr->ds_num = num;
nfs4_init_deviceid_node(&dsaddr->id_node, server, &pdev->dev_id);
INIT_LIST_HEAD(&dsaddrs);
for (i = 0; i < dsaddr->ds_num; i++) {
int j;
u32 mp_count;
p = xdr_inline_decode(&stream, 4);
if (unlikely(!p))
goto out_err_free_deviceid;
mp_count = be32_to_cpup(p); /* multipath count */
for (j = 0; j < mp_count; j++) {
da = nfs4_decode_mp_ds_addr(server->nfs_client->cl_net,
&stream, gfp_flags);
if (da)
list_add_tail(&da->da_node, &dsaddrs);
}
if (list_empty(&dsaddrs)) {
dprintk("%s: no suitable DS addresses found\n",
__func__);
goto out_err_free_deviceid;
}
dsaddr->ds_list[i] = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
if (!dsaddr->ds_list[i])
goto out_err_drain_dsaddrs;
/* If DS was already in cache, free ds addrs */
while (!list_empty(&dsaddrs)) {
da = list_first_entry(&dsaddrs,
struct nfs4_pnfs_ds_addr,
da_node);
list_del_init(&da->da_node);
kfree(da->da_remotestr);
kfree(da);
}
}
__free_page(scratch);
return dsaddr;
out_err_drain_dsaddrs:
while (!list_empty(&dsaddrs)) {
da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr,
da_node);
list_del_init(&da->da_node);
kfree(da->da_remotestr);
kfree(da);
}
out_err_free_deviceid:
nfs4_fl_free_deviceid(dsaddr);
/* stripe_indicies was part of dsaddr */
goto out_err_free_scratch;
out_err_free_stripe_indices:
kfree(stripe_indices);
out_err_free_scratch:
__free_page(scratch);
out_err:
dprintk("%s ERROR: returning NULL\n", __func__);
return NULL;
}
void
nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
{
nfs4_put_deviceid_node(&dsaddr->id_node);
}
/*
* Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
* Then: ((res + fsi) % dsaddr->stripe_count)
*/
u32
nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset)
{
struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
u64 tmp;
tmp = offset - flseg->pattern_offset;
do_div(tmp, flseg->stripe_unit);
tmp += flseg->first_stripe_index;
return do_div(tmp, flseg->dsaddr->stripe_count);
}
u32
nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
{
return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
}
struct nfs_fh *
nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
{
struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
u32 i;
if (flseg->stripe_type == STRIPE_SPARSE) {
if (flseg->num_fh == 1)
i = 0;
else if (flseg->num_fh == 0)
/* Use the MDS OPEN fh set in nfs_read_rpcsetup */
return NULL;
else
i = nfs4_fl_calc_ds_index(lseg, j);
} else
i = j;
return flseg->fh_array[i];
}
/* Upon return, either ds is connected, or ds is NULL */
struct nfs4_pnfs_ds *
nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
{
struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
struct nfs4_pnfs_ds *ret = ds;
struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
if (ds == NULL) {
printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
__func__, ds_idx);
pnfs_generic_mark_devid_invalid(devid);
goto out;
}
smp_rmb();
if (ds->ds_clp)
goto out_test_devid;
nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
dataserver_retrans, 4,
s->nfs_client->cl_minorversion,
s->nfs_client->cl_rpcclient->cl_auth->au_flavor);
out_test_devid:
if (filelayout_test_devid_unavailable(devid))
ret = NULL;
out:
return ret;
}
module_param(dataserver_retrans, uint, 0644);
MODULE_PARM_DESC(dataserver_retrans, "The number of times the NFSv4.1 client "
"retries a request before it attempts further "
" recovery action.");
module_param(dataserver_timeo, uint, 0644);
MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the "
"NFSv4.1 client waits for a response from a "
" data server before it retries an NFS request.");