swh:1:snp:c2847dfd741eae21606027cf29250d1ebcd63fb4
Tip revision: e26081808edadfd257c6c9d81014e3b25e9a6118 authored by Linus Torvalds on 18 May 2015, 17:13:47 UTC
Linux 4.1-rc4
Linux 4.1-rc4
Tip revision: e260818
nfs4layouts.c
/*
* Copyright (c) 2014 Christoph Hellwig.
*/
#include <linux/kmod.h>
#include <linux/file.h>
#include <linux/jhash.h>
#include <linux/sched.h>
#include <linux/sunrpc/addr.h>
#include "pnfs.h"
#include "netns.h"
#include "trace.h"
#define NFSDDBG_FACILITY NFSDDBG_PNFS
struct nfs4_layout {
struct list_head lo_perstate;
struct nfs4_layout_stateid *lo_state;
struct nfsd4_layout_seg lo_seg;
};
static struct kmem_cache *nfs4_layout_cache;
static struct kmem_cache *nfs4_layout_stateid_cache;
static struct nfsd4_callback_ops nfsd4_cb_layout_ops;
static const struct lock_manager_operations nfsd4_layouts_lm_ops;
const struct nfsd4_layout_ops *nfsd4_layout_ops[LAYOUT_TYPE_MAX] = {
[LAYOUT_BLOCK_VOLUME] = &bl_layout_ops,
};
/* pNFS device ID to export fsid mapping */
#define DEVID_HASH_BITS 8
#define DEVID_HASH_SIZE (1 << DEVID_HASH_BITS)
#define DEVID_HASH_MASK (DEVID_HASH_SIZE - 1)
static u64 nfsd_devid_seq = 1;
static struct list_head nfsd_devid_hash[DEVID_HASH_SIZE];
static DEFINE_SPINLOCK(nfsd_devid_lock);
static inline u32 devid_hashfn(u64 idx)
{
return jhash_2words(idx, idx >> 32, 0) & DEVID_HASH_MASK;
}
static void
nfsd4_alloc_devid_map(const struct svc_fh *fhp)
{
const struct knfsd_fh *fh = &fhp->fh_handle;
size_t fsid_len = key_len(fh->fh_fsid_type);
struct nfsd4_deviceid_map *map, *old;
int i;
map = kzalloc(sizeof(*map) + fsid_len, GFP_KERNEL);
if (!map)
return;
map->fsid_type = fh->fh_fsid_type;
memcpy(&map->fsid, fh->fh_fsid, fsid_len);
spin_lock(&nfsd_devid_lock);
if (fhp->fh_export->ex_devid_map)
goto out_unlock;
for (i = 0; i < DEVID_HASH_SIZE; i++) {
list_for_each_entry(old, &nfsd_devid_hash[i], hash) {
if (old->fsid_type != fh->fh_fsid_type)
continue;
if (memcmp(old->fsid, fh->fh_fsid,
key_len(old->fsid_type)))
continue;
fhp->fh_export->ex_devid_map = old;
goto out_unlock;
}
}
map->idx = nfsd_devid_seq++;
list_add_tail_rcu(&map->hash, &nfsd_devid_hash[devid_hashfn(map->idx)]);
fhp->fh_export->ex_devid_map = map;
map = NULL;
out_unlock:
spin_unlock(&nfsd_devid_lock);
kfree(map);
}
struct nfsd4_deviceid_map *
nfsd4_find_devid_map(int idx)
{
struct nfsd4_deviceid_map *map, *ret = NULL;
rcu_read_lock();
list_for_each_entry_rcu(map, &nfsd_devid_hash[devid_hashfn(idx)], hash)
if (map->idx == idx)
ret = map;
rcu_read_unlock();
return ret;
}
int
nfsd4_set_deviceid(struct nfsd4_deviceid *id, const struct svc_fh *fhp,
u32 device_generation)
{
if (!fhp->fh_export->ex_devid_map) {
nfsd4_alloc_devid_map(fhp);
if (!fhp->fh_export->ex_devid_map)
return -ENOMEM;
}
id->fsid_idx = fhp->fh_export->ex_devid_map->idx;
id->generation = device_generation;
id->pad = 0;
return 0;
}
void nfsd4_setup_layout_type(struct svc_export *exp)
{
struct super_block *sb = exp->ex_path.mnt->mnt_sb;
if (!(exp->ex_flags & NFSEXP_PNFS))
return;
if (sb->s_export_op->get_uuid &&
sb->s_export_op->map_blocks &&
sb->s_export_op->commit_blocks)
exp->ex_layout_type = LAYOUT_BLOCK_VOLUME;
}
static void
nfsd4_free_layout_stateid(struct nfs4_stid *stid)
{
struct nfs4_layout_stateid *ls = layoutstateid(stid);
struct nfs4_client *clp = ls->ls_stid.sc_client;
struct nfs4_file *fp = ls->ls_stid.sc_file;
trace_layoutstate_free(&ls->ls_stid.sc_stateid);
spin_lock(&clp->cl_lock);
list_del_init(&ls->ls_perclnt);
spin_unlock(&clp->cl_lock);
spin_lock(&fp->fi_lock);
list_del_init(&ls->ls_perfile);
spin_unlock(&fp->fi_lock);
vfs_setlease(ls->ls_file, F_UNLCK, NULL, (void **)&ls);
fput(ls->ls_file);
if (ls->ls_recalled)
atomic_dec(&ls->ls_stid.sc_file->fi_lo_recalls);
kmem_cache_free(nfs4_layout_stateid_cache, ls);
}
static int
nfsd4_layout_setlease(struct nfs4_layout_stateid *ls)
{
struct file_lock *fl;
int status;
fl = locks_alloc_lock();
if (!fl)
return -ENOMEM;
locks_init_lock(fl);
fl->fl_lmops = &nfsd4_layouts_lm_ops;
fl->fl_flags = FL_LAYOUT;
fl->fl_type = F_RDLCK;
fl->fl_end = OFFSET_MAX;
fl->fl_owner = ls;
fl->fl_pid = current->tgid;
fl->fl_file = ls->ls_file;
status = vfs_setlease(fl->fl_file, fl->fl_type, &fl, NULL);
if (status) {
locks_free_lock(fl);
return status;
}
BUG_ON(fl != NULL);
return 0;
}
static struct nfs4_layout_stateid *
nfsd4_alloc_layout_stateid(struct nfsd4_compound_state *cstate,
struct nfs4_stid *parent, u32 layout_type)
{
struct nfs4_client *clp = cstate->clp;
struct nfs4_file *fp = parent->sc_file;
struct nfs4_layout_stateid *ls;
struct nfs4_stid *stp;
stp = nfs4_alloc_stid(cstate->clp, nfs4_layout_stateid_cache);
if (!stp)
return NULL;
stp->sc_free = nfsd4_free_layout_stateid;
get_nfs4_file(fp);
stp->sc_file = fp;
ls = layoutstateid(stp);
INIT_LIST_HEAD(&ls->ls_perclnt);
INIT_LIST_HEAD(&ls->ls_perfile);
spin_lock_init(&ls->ls_lock);
INIT_LIST_HEAD(&ls->ls_layouts);
ls->ls_layout_type = layout_type;
nfsd4_init_cb(&ls->ls_recall, clp, &nfsd4_cb_layout_ops,
NFSPROC4_CLNT_CB_LAYOUT);
if (parent->sc_type == NFS4_DELEG_STID)
ls->ls_file = get_file(fp->fi_deleg_file);
else
ls->ls_file = find_any_file(fp);
BUG_ON(!ls->ls_file);
if (nfsd4_layout_setlease(ls)) {
put_nfs4_file(fp);
kmem_cache_free(nfs4_layout_stateid_cache, ls);
return NULL;
}
spin_lock(&clp->cl_lock);
stp->sc_type = NFS4_LAYOUT_STID;
list_add(&ls->ls_perclnt, &clp->cl_lo_states);
spin_unlock(&clp->cl_lock);
spin_lock(&fp->fi_lock);
list_add(&ls->ls_perfile, &fp->fi_lo_states);
spin_unlock(&fp->fi_lock);
trace_layoutstate_alloc(&ls->ls_stid.sc_stateid);
return ls;
}
__be32
nfsd4_preprocess_layout_stateid(struct svc_rqst *rqstp,
struct nfsd4_compound_state *cstate, stateid_t *stateid,
bool create, u32 layout_type, struct nfs4_layout_stateid **lsp)
{
struct nfs4_layout_stateid *ls;
struct nfs4_stid *stid;
unsigned char typemask = NFS4_LAYOUT_STID;
__be32 status;
if (create)
typemask |= (NFS4_OPEN_STID | NFS4_LOCK_STID | NFS4_DELEG_STID);
status = nfsd4_lookup_stateid(cstate, stateid, typemask, &stid,
net_generic(SVC_NET(rqstp), nfsd_net_id));
if (status)
goto out;
if (!fh_match(&cstate->current_fh.fh_handle,
&stid->sc_file->fi_fhandle)) {
status = nfserr_bad_stateid;
goto out_put_stid;
}
if (stid->sc_type != NFS4_LAYOUT_STID) {
ls = nfsd4_alloc_layout_stateid(cstate, stid, layout_type);
nfs4_put_stid(stid);
status = nfserr_jukebox;
if (!ls)
goto out;
} else {
ls = container_of(stid, struct nfs4_layout_stateid, ls_stid);
status = nfserr_bad_stateid;
if (stateid->si_generation > stid->sc_stateid.si_generation)
goto out_put_stid;
if (layout_type != ls->ls_layout_type)
goto out_put_stid;
}
*lsp = ls;
return 0;
out_put_stid:
nfs4_put_stid(stid);
out:
return status;
}
static void
nfsd4_recall_file_layout(struct nfs4_layout_stateid *ls)
{
spin_lock(&ls->ls_lock);
if (ls->ls_recalled)
goto out_unlock;
ls->ls_recalled = true;
atomic_inc(&ls->ls_stid.sc_file->fi_lo_recalls);
if (list_empty(&ls->ls_layouts))
goto out_unlock;
trace_layout_recall(&ls->ls_stid.sc_stateid);
atomic_inc(&ls->ls_stid.sc_count);
update_stateid(&ls->ls_stid.sc_stateid);
memcpy(&ls->ls_recall_sid, &ls->ls_stid.sc_stateid, sizeof(stateid_t));
nfsd4_run_cb(&ls->ls_recall);
out_unlock:
spin_unlock(&ls->ls_lock);
}
static inline u64
layout_end(struct nfsd4_layout_seg *seg)
{
u64 end = seg->offset + seg->length;
return end >= seg->offset ? end : NFS4_MAX_UINT64;
}
static void
layout_update_len(struct nfsd4_layout_seg *lo, u64 end)
{
if (end == NFS4_MAX_UINT64)
lo->length = NFS4_MAX_UINT64;
else
lo->length = end - lo->offset;
}
static bool
layouts_overlapping(struct nfs4_layout *lo, struct nfsd4_layout_seg *s)
{
if (s->iomode != IOMODE_ANY && s->iomode != lo->lo_seg.iomode)
return false;
if (layout_end(&lo->lo_seg) <= s->offset)
return false;
if (layout_end(s) <= lo->lo_seg.offset)
return false;
return true;
}
static bool
layouts_try_merge(struct nfsd4_layout_seg *lo, struct nfsd4_layout_seg *new)
{
if (lo->iomode != new->iomode)
return false;
if (layout_end(new) < lo->offset)
return false;
if (layout_end(lo) < new->offset)
return false;
lo->offset = min(lo->offset, new->offset);
layout_update_len(lo, max(layout_end(lo), layout_end(new)));
return true;
}
static __be32
nfsd4_recall_conflict(struct nfs4_layout_stateid *ls)
{
struct nfs4_file *fp = ls->ls_stid.sc_file;
struct nfs4_layout_stateid *l, *n;
__be32 nfserr = nfs_ok;
assert_spin_locked(&fp->fi_lock);
list_for_each_entry_safe(l, n, &fp->fi_lo_states, ls_perfile) {
if (l != ls) {
nfsd4_recall_file_layout(l);
nfserr = nfserr_recallconflict;
}
}
return nfserr;
}
__be32
nfsd4_insert_layout(struct nfsd4_layoutget *lgp, struct nfs4_layout_stateid *ls)
{
struct nfsd4_layout_seg *seg = &lgp->lg_seg;
struct nfs4_file *fp = ls->ls_stid.sc_file;
struct nfs4_layout *lp, *new = NULL;
__be32 nfserr;
spin_lock(&fp->fi_lock);
nfserr = nfsd4_recall_conflict(ls);
if (nfserr)
goto out;
spin_lock(&ls->ls_lock);
list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
if (layouts_try_merge(&lp->lo_seg, seg))
goto done;
}
spin_unlock(&ls->ls_lock);
spin_unlock(&fp->fi_lock);
new = kmem_cache_alloc(nfs4_layout_cache, GFP_KERNEL);
if (!new)
return nfserr_jukebox;
memcpy(&new->lo_seg, seg, sizeof(lp->lo_seg));
new->lo_state = ls;
spin_lock(&fp->fi_lock);
nfserr = nfsd4_recall_conflict(ls);
if (nfserr)
goto out;
spin_lock(&ls->ls_lock);
list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
if (layouts_try_merge(&lp->lo_seg, seg))
goto done;
}
atomic_inc(&ls->ls_stid.sc_count);
list_add_tail(&new->lo_perstate, &ls->ls_layouts);
new = NULL;
done:
update_stateid(&ls->ls_stid.sc_stateid);
memcpy(&lgp->lg_sid, &ls->ls_stid.sc_stateid, sizeof(stateid_t));
spin_unlock(&ls->ls_lock);
out:
spin_unlock(&fp->fi_lock);
if (new)
kmem_cache_free(nfs4_layout_cache, new);
return nfserr;
}
static void
nfsd4_free_layouts(struct list_head *reaplist)
{
while (!list_empty(reaplist)) {
struct nfs4_layout *lp = list_first_entry(reaplist,
struct nfs4_layout, lo_perstate);
list_del(&lp->lo_perstate);
nfs4_put_stid(&lp->lo_state->ls_stid);
kmem_cache_free(nfs4_layout_cache, lp);
}
}
static void
nfsd4_return_file_layout(struct nfs4_layout *lp, struct nfsd4_layout_seg *seg,
struct list_head *reaplist)
{
struct nfsd4_layout_seg *lo = &lp->lo_seg;
u64 end = layout_end(lo);
if (seg->offset <= lo->offset) {
if (layout_end(seg) >= end) {
list_move_tail(&lp->lo_perstate, reaplist);
return;
}
lo->offset = layout_end(seg);
} else {
/* retain the whole layout segment on a split. */
if (layout_end(seg) < end) {
dprintk("%s: split not supported\n", __func__);
return;
}
end = seg->offset;
}
layout_update_len(lo, end);
}
__be32
nfsd4_return_file_layouts(struct svc_rqst *rqstp,
struct nfsd4_compound_state *cstate,
struct nfsd4_layoutreturn *lrp)
{
struct nfs4_layout_stateid *ls;
struct nfs4_layout *lp, *n;
LIST_HEAD(reaplist);
__be32 nfserr;
int found = 0;
nfserr = nfsd4_preprocess_layout_stateid(rqstp, cstate, &lrp->lr_sid,
false, lrp->lr_layout_type,
&ls);
if (nfserr) {
trace_layout_return_lookup_fail(&lrp->lr_sid);
return nfserr;
}
spin_lock(&ls->ls_lock);
list_for_each_entry_safe(lp, n, &ls->ls_layouts, lo_perstate) {
if (layouts_overlapping(lp, &lrp->lr_seg)) {
nfsd4_return_file_layout(lp, &lrp->lr_seg, &reaplist);
found++;
}
}
if (!list_empty(&ls->ls_layouts)) {
if (found) {
update_stateid(&ls->ls_stid.sc_stateid);
memcpy(&lrp->lr_sid, &ls->ls_stid.sc_stateid,
sizeof(stateid_t));
}
lrp->lrs_present = 1;
} else {
trace_layoutstate_unhash(&ls->ls_stid.sc_stateid);
nfs4_unhash_stid(&ls->ls_stid);
lrp->lrs_present = 0;
}
spin_unlock(&ls->ls_lock);
nfs4_put_stid(&ls->ls_stid);
nfsd4_free_layouts(&reaplist);
return nfs_ok;
}
__be32
nfsd4_return_client_layouts(struct svc_rqst *rqstp,
struct nfsd4_compound_state *cstate,
struct nfsd4_layoutreturn *lrp)
{
struct nfs4_layout_stateid *ls, *n;
struct nfs4_client *clp = cstate->clp;
struct nfs4_layout *lp, *t;
LIST_HEAD(reaplist);
lrp->lrs_present = 0;
spin_lock(&clp->cl_lock);
list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt) {
if (ls->ls_layout_type != lrp->lr_layout_type)
continue;
if (lrp->lr_return_type == RETURN_FSID &&
!fh_fsid_match(&ls->ls_stid.sc_file->fi_fhandle,
&cstate->current_fh.fh_handle))
continue;
spin_lock(&ls->ls_lock);
list_for_each_entry_safe(lp, t, &ls->ls_layouts, lo_perstate) {
if (lrp->lr_seg.iomode == IOMODE_ANY ||
lrp->lr_seg.iomode == lp->lo_seg.iomode)
list_move_tail(&lp->lo_perstate, &reaplist);
}
spin_unlock(&ls->ls_lock);
}
spin_unlock(&clp->cl_lock);
nfsd4_free_layouts(&reaplist);
return 0;
}
static void
nfsd4_return_all_layouts(struct nfs4_layout_stateid *ls,
struct list_head *reaplist)
{
spin_lock(&ls->ls_lock);
list_splice_init(&ls->ls_layouts, reaplist);
spin_unlock(&ls->ls_lock);
}
void
nfsd4_return_all_client_layouts(struct nfs4_client *clp)
{
struct nfs4_layout_stateid *ls, *n;
LIST_HEAD(reaplist);
spin_lock(&clp->cl_lock);
list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt)
nfsd4_return_all_layouts(ls, &reaplist);
spin_unlock(&clp->cl_lock);
nfsd4_free_layouts(&reaplist);
}
void
nfsd4_return_all_file_layouts(struct nfs4_client *clp, struct nfs4_file *fp)
{
struct nfs4_layout_stateid *ls, *n;
LIST_HEAD(reaplist);
spin_lock(&fp->fi_lock);
list_for_each_entry_safe(ls, n, &fp->fi_lo_states, ls_perfile) {
if (ls->ls_stid.sc_client == clp)
nfsd4_return_all_layouts(ls, &reaplist);
}
spin_unlock(&fp->fi_lock);
nfsd4_free_layouts(&reaplist);
}
static void
nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls)
{
struct nfs4_client *clp = ls->ls_stid.sc_client;
char addr_str[INET6_ADDRSTRLEN];
static char *envp[] = {
"HOME=/",
"TERM=linux",
"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
NULL
};
char *argv[8];
int error;
rpc_ntop((struct sockaddr *)&clp->cl_addr, addr_str, sizeof(addr_str));
trace_layout_recall_fail(&ls->ls_stid.sc_stateid);
printk(KERN_WARNING
"nfsd: client %s failed to respond to layout recall. "
" Fencing..\n", addr_str);
argv[0] = "/sbin/nfsd-recall-failed";
argv[1] = addr_str;
argv[2] = ls->ls_file->f_path.mnt->mnt_sb->s_id;
argv[3] = NULL;
error = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
if (error) {
printk(KERN_ERR "nfsd: fence failed for client %s: %d!\n",
addr_str, error);
}
}
static int
nfsd4_cb_layout_done(struct nfsd4_callback *cb, struct rpc_task *task)
{
struct nfs4_layout_stateid *ls =
container_of(cb, struct nfs4_layout_stateid, ls_recall);
LIST_HEAD(reaplist);
switch (task->tk_status) {
case 0:
return 1;
case -NFS4ERR_NOMATCHING_LAYOUT:
trace_layout_recall_done(&ls->ls_stid.sc_stateid);
task->tk_status = 0;
return 1;
case -NFS4ERR_DELAY:
/* Poll the client until it's done with the layout */
/* FIXME: cap number of retries.
* The pnfs standard states that we need to only expire
* the client after at-least "lease time" .eg lease-time * 2
* when failing to communicate a recall
*/
rpc_delay(task, HZ/100); /* 10 mili-seconds */
return 0;
default:
/*
* Unknown error or non-responding client, we'll need to fence.
*/
nfsd4_cb_layout_fail(ls);
return -1;
}
}
static void
nfsd4_cb_layout_release(struct nfsd4_callback *cb)
{
struct nfs4_layout_stateid *ls =
container_of(cb, struct nfs4_layout_stateid, ls_recall);
LIST_HEAD(reaplist);
trace_layout_recall_release(&ls->ls_stid.sc_stateid);
nfsd4_return_all_layouts(ls, &reaplist);
nfsd4_free_layouts(&reaplist);
nfs4_put_stid(&ls->ls_stid);
}
static struct nfsd4_callback_ops nfsd4_cb_layout_ops = {
.done = nfsd4_cb_layout_done,
.release = nfsd4_cb_layout_release,
};
static bool
nfsd4_layout_lm_break(struct file_lock *fl)
{
/*
* We don't want the locks code to timeout the lease for us;
* we'll remove it ourself if a layout isn't returned
* in time:
*/
fl->fl_break_time = 0;
nfsd4_recall_file_layout(fl->fl_owner);
return false;
}
static int
nfsd4_layout_lm_change(struct file_lock *onlist, int arg,
struct list_head *dispose)
{
BUG_ON(!(arg & F_UNLCK));
return lease_modify(onlist, arg, dispose);
}
static const struct lock_manager_operations nfsd4_layouts_lm_ops = {
.lm_break = nfsd4_layout_lm_break,
.lm_change = nfsd4_layout_lm_change,
};
int
nfsd4_init_pnfs(void)
{
int i;
for (i = 0; i < DEVID_HASH_SIZE; i++)
INIT_LIST_HEAD(&nfsd_devid_hash[i]);
nfs4_layout_cache = kmem_cache_create("nfs4_layout",
sizeof(struct nfs4_layout), 0, 0, NULL);
if (!nfs4_layout_cache)
return -ENOMEM;
nfs4_layout_stateid_cache = kmem_cache_create("nfs4_layout_stateid",
sizeof(struct nfs4_layout_stateid), 0, 0, NULL);
if (!nfs4_layout_stateid_cache) {
kmem_cache_destroy(nfs4_layout_cache);
return -ENOMEM;
}
return 0;
}
void
nfsd4_exit_pnfs(void)
{
int i;
kmem_cache_destroy(nfs4_layout_cache);
kmem_cache_destroy(nfs4_layout_stateid_cache);
for (i = 0; i < DEVID_HASH_SIZE; i++) {
struct nfsd4_deviceid_map *map, *n;
list_for_each_entry_safe(map, n, &nfsd_devid_hash[i], hash)
kfree(map);
}
}