| Message ID | 20231027015613.26247-4-neilb@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | support admin-revocation of v4 state | expand |
Hi NeilBrown,
kernel test robot noticed the following build errors:
[auto build test ERROR on linus/master]
[also build test ERROR on v6.6 next-20231030]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/NeilBrown/nfsd-prepare-for-supporting-admin-revocation-of-state/20231027-095832
base: linus/master
patch link: https://lore.kernel.org/r/20231027015613.26247-4-neilb%40suse.de
patch subject: [PATCH 3/6] nfsd: allow admin-revoked NFSv4.0 state to be freed.
config: i386-allmodconfig (https://download.01.org/0day-ci/archive/20231031/202310310756.sZ0piSTX-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231031/202310310756.sZ0piSTX-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202310310756.sZ0piSTX-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from <command-line>:
fs/nfsd/nfs4state.c: In function 'nfsd4_revoke_states':
>> include/linux/compiler_types.h:425:45: error: call to '__compiletime_assert_955' declared with attribute error: Need native word sized stores/loads for atomicity.
425 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^
include/linux/compiler_types.h:406:25: note: in definition of macro '__compiletime_assert'
406 | prefix ## suffix(); \
| ^~~~~~
include/linux/compiler_types.h:425:9: note: in expansion of macro '_compiletime_assert'
425 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/compiler_types.h:428:9: note: in expansion of macro 'compiletime_assert'
428 | compiletime_assert(__native_word(t), \
| ^~~~~~~~~~~~~~~~~~
arch/x86/include/asm/barrier.h:65:9: note: in expansion of macro 'compiletime_assert_atomic_type'
65 | compiletime_assert_atomic_type(*p); \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/asm-generic/barrier.h:172:55: note: in expansion of macro '__smp_store_release'
172 | #define smp_store_release(p, v) do { kcsan_release(); __smp_store_release(p, v); } while (0)
| ^~~~~~~~~~~~~~~~~~~
fs/nfsd/nfs4state.c:1725:41: note: in expansion of macro 'smp_store_release'
1725 | smp_store_release(&nn->nfs40_last_revoke,
| ^~~~~~~~~~~~~~~~~
In function 'nfs40_clean_admin_revoked',
inlined from 'nfs4_laundromat' at fs/nfsd/nfs4state.c:6304:2:
include/linux/compiler_types.h:425:45: error: call to '__compiletime_assert_989' declared with attribute error: Need native word sized stores/loads for atomicity.
425 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^
include/linux/compiler_types.h:406:25: note: in definition of macro '__compiletime_assert'
406 | prefix ## suffix(); \
| ^~~~~~
include/linux/compiler_types.h:425:9: note: in expansion of macro '_compiletime_assert'
425 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/compiler_types.h:428:9: note: in expansion of macro 'compiletime_assert'
428 | compiletime_assert(__native_word(t), \
| ^~~~~~~~~~~~~~~~~~
arch/x86/include/asm/barrier.h:73:9: note: in expansion of macro 'compiletime_assert_atomic_type'
73 | compiletime_assert_atomic_type(*p); \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/asm-generic/barrier.h:176:29: note: in expansion of macro '__smp_load_acquire'
176 | #define smp_load_acquire(p) __smp_load_acquire(p)
| ^~~~~~~~~~~~~~~~~~
fs/nfsd/nfs4state.c:6242:13: note: in expansion of macro 'smp_load_acquire'
6242 | if (smp_load_acquire(&nn->nfs40_last_revoke) == 0 ||
| ^~~~~~~~~~~~~~~~
vim +/__compiletime_assert_955 +425 include/linux/compiler_types.h
eb5c2d4b45e3d2 Will Deacon 2020-07-21 411
eb5c2d4b45e3d2 Will Deacon 2020-07-21 412 #define _compiletime_assert(condition, msg, prefix, suffix) \
eb5c2d4b45e3d2 Will Deacon 2020-07-21 413 __compiletime_assert(condition, msg, prefix, suffix)
eb5c2d4b45e3d2 Will Deacon 2020-07-21 414
eb5c2d4b45e3d2 Will Deacon 2020-07-21 415 /**
eb5c2d4b45e3d2 Will Deacon 2020-07-21 416 * compiletime_assert - break build and emit msg if condition is false
eb5c2d4b45e3d2 Will Deacon 2020-07-21 417 * @condition: a compile-time constant condition to check
eb5c2d4b45e3d2 Will Deacon 2020-07-21 418 * @msg: a message to emit if condition is false
eb5c2d4b45e3d2 Will Deacon 2020-07-21 419 *
eb5c2d4b45e3d2 Will Deacon 2020-07-21 420 * In tradition of POSIX assert, this macro will break the build if the
eb5c2d4b45e3d2 Will Deacon 2020-07-21 421 * supplied condition is *false*, emitting the supplied error message if the
eb5c2d4b45e3d2 Will Deacon 2020-07-21 422 * compiler has support to do so.
eb5c2d4b45e3d2 Will Deacon 2020-07-21 423 */
eb5c2d4b45e3d2 Will Deacon 2020-07-21 424 #define compiletime_assert(condition, msg) \
eb5c2d4b45e3d2 Will Deacon 2020-07-21 @425 _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
eb5c2d4b45e3d2 Will Deacon 2020-07-21 426
diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h index ec49b200b797..02f8fa095b0f 100644 --- a/fs/nfsd/netns.h +++ b/fs/nfsd/netns.h @@ -197,6 +197,10 @@ struct nfsd_net { atomic_t nfsd_courtesy_clients; struct shrinker nfsd_client_shrinker; struct work_struct nfsd_shrinker_work; + + /* last time an admin-revoke happened for NFSv4.0 */ + time64_t nfs40_last_revoke; + }; /* Simple check to find out if a given net was properly initialized */ diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index e15d35c57991..cea36f3ff204 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -1723,6 +1723,14 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb) switch (stid->sc_type) { } nfs4_put_stid(stid); + if (clp->cl_minorversion == 0) + /* Allow cleanup after a lease period. + * store_release ensures cleanup will + * see any newly revoked states if it + * sees the time updated. + */ + smp_store_release(&nn->nfs40_last_revoke, + ktime_get_boottime_seconds()); spin_lock(&nn->client_lock); goto retry; } @@ -4645,6 +4653,39 @@ nfsd4_find_existing_open(struct nfs4_file *fp, struct nfsd4_open *open) return ret; } +static void nfsd_drop_revoked_stid(struct nfs4_stid *s) +{ + struct nfs4_client *cl = s->sc_client; + + switch (s->sc_type) { + default: + spin_unlock(&cl->cl_lock); + } +} + +static void nfs40_drop_revoked_stid(struct nfs4_client *cl, + stateid_t *stid) +{ + /* NFSv4.0 has no way for the client to tell the server + * that it can forget an admin-revoked stateid. + * So we keep it around until the first time that the + * client uses it, and drop it the first time + * nfserr_admin_revoked is returned. + * For v4.1 and later we wait until explicitly told + * to free the stateid. + */ + if (cl->cl_minorversion == 0) { + struct nfs4_stid *st; + + spin_lock(&cl->cl_lock); + st = find_stateid_locked(cl, stid); + if (st) + nfsd_drop_revoked_stid(st); + else + spin_unlock(&cl->cl_lock); + } +} + static __be32 nfsd4_verify_open_stid(struct nfs4_stid *s) { @@ -4672,6 +4713,10 @@ nfsd4_lock_ol_stateid(struct nfs4_ol_stateid *stp) mutex_lock_nested(&stp->st_mutex, LOCK_STATEID_MUTEX); ret = nfsd4_verify_open_stid(&stp->st_stid); + if (ret == nfserr_admin_revoked) + nfs40_drop_revoked_stid(stp->st_stid.sc_client, + &stp->st_stid.sc_stateid); + if (ret != nfs_ok) mutex_unlock(&stp->st_mutex); return ret; @@ -5256,6 +5301,7 @@ nfs4_check_deleg(struct nfs4_client *cl, struct nfsd4_open *open, } if (deleg->dl_stid.sc_type == NFS4_ADMIN_REVOKED_DELEG_STID) { nfs4_put_stid(&deleg->dl_stid); + nfs40_drop_revoked_stid(cl, &open->op_delegate_stateid); status = nfserr_admin_revoked; goto out; } @@ -6253,6 +6299,41 @@ nfs4_process_client_reaplist(struct list_head *reaplist) } } +static void nfs40_clean_admin_revoked(struct nfsd_net *nn, + struct laundry_time *lt) +{ + struct nfs4_client *clp; + + /* load_acquire avoids races with nfsd4_revoke_states() */ + if (smp_load_acquire(&nn->nfs40_last_revoke) == 0 || + nn->nfs40_last_revoke > lt->cutoff) + return; + + nn->nfs40_last_revoke = 0; + +retry: + spin_lock(&nn->client_lock); + list_for_each_entry(clp, &nn->client_lru, cl_lru) { + unsigned long id, tmp; + struct nfs4_stid *stid; + + if (atomic_read(&clp->cl_admin_revoked) == 0) + continue; + + spin_lock(&clp->cl_lock); + idr_for_each_entry_ul(&clp->cl_stateids, stid, tmp, id) + if (stid->sc_type & NFS4_ALL_ADMIN_REVOKED_STIDS) { + refcount_inc(&stid->sc_count); + spin_unlock(&nn->client_lock); + nfsd_drop_revoked_stid(stid); + nfs4_put_stid(stid); + goto retry; + } + spin_unlock(&clp->cl_lock); + } + spin_unlock(&nn->client_lock); +} + static time64_t nfs4_laundromat(struct nfsd_net *nn) { @@ -6286,6 +6367,8 @@ nfs4_laundromat(struct nfsd_net *nn) nfs4_get_client_reaplist(nn, &reaplist, <); nfs4_process_client_reaplist(&reaplist); + nfs40_clean_admin_revoked(nn, <); + spin_lock(&state_lock); list_for_each_safe(pos, next, &nn->del_recall_lru) { dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru); @@ -6504,6 +6587,9 @@ static __be32 nfsd4_stid_check_stateid_generation(stateid_t *in, struct nfs4_sti if (ret == nfs_ok) ret = check_stateid_generation(in, &s->sc_stateid, has_session); spin_unlock(&s->sc_lock); + if (ret == nfserr_admin_revoked) + nfs40_drop_revoked_stid(s->sc_client, + &s->sc_stateid); return ret; } @@ -6555,6 +6641,8 @@ static __be32 nfsd4_validate_stateid(struct nfs4_client *cl, stateid_t *stateid) } out_unlock: spin_unlock(&cl->cl_lock); + if (status == nfserr_admin_revoked) + nfs40_drop_revoked_stid(cl, stateid); return status; } @@ -6604,6 +6692,7 @@ nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate, return nfserr_bad_stateid; } if (stid->sc_type & NFS4_ALL_ADMIN_REVOKED_STIDS) { + nfs40_drop_revoked_stid(cstate->clp, stateid); nfs4_put_stid(stid); return nfserr_admin_revoked; } @@ -6923,6 +7012,13 @@ nfsd4_free_stateid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, nfs4_put_stid(s); ret = nfs_ok; goto out; + case NFS4_ADMIN_REVOKED_STID: + case NFS4_ADMIN_REVOKED_LOCK_STID: + case NFS4_ADMIN_REVOKED_DELEG_STID: + spin_unlock(&s->sc_lock); + nfsd_drop_revoked_stid(s); + ret = nfs_ok; + goto out; /* Default falls through and returns nfserr_bad_stateid */ } spin_unlock(&s->sc_lock);
For NFSv4.1 and later the client easily discovers if there is any admin-revoked state and will then find and explicitly free it. For NFSv4.0 there is no such mechanism. The client can only find that state is admin-revoked if it tries to use that state, and there is no way for it to explicitly free the state. So the server must hold on to, at least, the stateid for an indefinite amount of time. A RELEASE_LOCKOWNER request might justify forgetting some of these stateids, as would the whole clients lease lapsing, but these are not reliable. This patch takes two approaches. Whenever a client uses an revoked stateid, that stateid is then discarded and will not be recognised again. This might confuse a client which expect to get NFS4ERR_ADMIN_REVOKED consistently once it get it at all, but should mostly work. Hopefully one error will lead to other resources being closed (e.g. process exits), which will result in more stateid being freed when a CLOSE attempt gets NFS4ERR_ADMIN_REVOKED. Also, any admin-revoked stateids that have been that way for more than one lease time are periodically revoke. No actual freeing of state happens in this patch. That will come in future patches which handle the different sorts of revoked state. Signed-off-by: NeilBrown <neilb@suse.de> --- fs/nfsd/netns.h | 4 ++ fs/nfsd/nfs4state.c | 96 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 100 insertions(+)