Merge branch 'for-3.16' of git://linux-nfs.org/~bfields/linux (147f1404) · Commits · 戴 / test

fs/nfsd/nfs4state.c

+78 −0

Original line number	Diff line number	Diff line
		@@ -41,6 +41,7 @@
		#include <linux/ratelimit.h>
		#include <linux/sunrpc/svcauth_gss.h>
		#include <linux/sunrpc/addr.h>
		#include <linux/hash.h>
		#include "xdr4.h"
		#include "xdr4cb.h"
		#include "vfs.h"
		@@ -364,6 +365,79 @@ static struct nfs4_ol_stateid * nfs4_alloc_stateid(struct nfs4_client *clp)
		return openlockstateid(nfs4_alloc_stid(clp, stateid_slab));
		}

		/*
		* When we recall a delegation, we should be careful not to hand it
		* out again straight away.
		* To ensure this we keep a pair of bloom filters ('new' and 'old')
		* in which the filehandles of recalled delegations are "stored".
		* If a filehandle appear in either filter, a delegation is blocked.
		* When a delegation is recalled, the filehandle is stored in the "new"
		* filter.
		* Every 30 seconds we swap the filters and clear the "new" one,
		* unless both are empty of course.
		*
		* Each filter is 256 bits. We hash the filehandle to 32bit and use the
		* low 3 bytes as hash-table indices.
		*
		* 'state_lock', which is always held when block_delegations() is called,
		* is used to manage concurrent access. Testing does not need the lock
		* except when swapping the two filters.
		*/
		static struct bloom_pair {
		int entries, old_entries;
		time_t swap_time;
		int new; /* index into 'set' */
		DECLARE_BITMAP(set[2], 256);
		} blocked_delegations;

		static int delegation_blocked(struct knfsd_fh *fh)
		{
		u32 hash;
		struct bloom_pair *bd = &blocked_delegations;

		if (bd->entries == 0)
		return 0;
		if (seconds_since_boot() - bd->swap_time > 30) {
		spin_lock(&state_lock);
		if (seconds_since_boot() - bd->swap_time > 30) {
		bd->entries -= bd->old_entries;
		bd->old_entries = bd->entries;
		memset(bd->set[bd->new], 0,
		sizeof(bd->set[0]));
		bd->new = 1-bd->new;
		bd->swap_time = seconds_since_boot();
		}
		spin_unlock(&state_lock);
		}
		hash = arch_fast_hash(&fh->fh_base, fh->fh_size, 0);
		if (test_bit(hash&255, bd->set[0]) &&
		test_bit((hash>>8)&255, bd->set[0]) &&
		test_bit((hash>>16)&255, bd->set[0]))
		return 1;

		if (test_bit(hash&255, bd->set[1]) &&
		test_bit((hash>>8)&255, bd->set[1]) &&
		test_bit((hash>>16)&255, bd->set[1]))
		return 1;

		return 0;
		}

		static void block_delegations(struct knfsd_fh *fh)
		{
		u32 hash;
		struct bloom_pair *bd = &blocked_delegations;

		hash = arch_fast_hash(&fh->fh_base, fh->fh_size, 0);

		__set_bit(hash&255, bd->set[bd->new]);
		__set_bit((hash>>8)&255, bd->set[bd->new]);
		__set_bit((hash>>16)&255, bd->set[bd->new]);
		if (bd->entries == 0)
		bd->swap_time = seconds_since_boot();
		bd->entries += 1;
		}

		static struct nfs4_delegation *
		alloc_init_deleg(struct nfs4_client clp, struct nfs4_ol_stateid stp, struct svc_fh *current_fh)
		{
		@@ -372,6 +446,8 @@ alloc_init_deleg(struct nfs4_client clp, struct nfs4_ol_stateid stp, struct sv
		dprintk("NFSD alloc_init_deleg\n");
		if (num_delegations > max_delegations)
		return NULL;
		if (delegation_blocked(&current_fh->fh_handle))
		return NULL;
		dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab));
		if (dp == NULL)
		return dp;
		@@ -2770,6 +2846,8 @@ static void nfsd_break_one_deleg(struct nfs4_delegation *dp)
		/* Only place dl_time is set; protected by i_lock: */
		dp->dl_time = get_seconds();

		block_delegations(&dp->dl_fh);

		nfsd4_cb_recall(dp);
		}

fs/nfsd/nfs4xdr.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -2687,6 +2687,7 @@ nfsd4_encode_dirent(void ccdv, const char name, int namlen,
		nfserr = nfserr_toosmall;
		goto fail;
		case nfserr_noent:
		xdr_truncate_encode(xdr, start_offset);
		goto skip_entry;
		default:
		/*

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