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@@ -1,270 +0,0 @@
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-/*
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- * net/tipc/ref.c: TIPC socket registry code
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- *
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- * Copyright (c) 1991-2006, 2014, Ericsson AB
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- * Copyright (c) 2004-2007, Wind River Systems
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- * All rights reserved.
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- *
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- * Redistribution and use in source and binary forms, with or without
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- * modification, are permitted provided that the following conditions are met:
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- *
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- * 1. Redistributions of source code must retain the above copyright
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- * notice, this list of conditions and the following disclaimer.
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- * 2. Redistributions in binary form must reproduce the above copyright
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- * notice, this list of conditions and the following disclaimer in the
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- * documentation and/or other materials provided with the distribution.
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- * 3. Neither the names of the copyright holders nor the names of its
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- * contributors may be used to endorse or promote products derived from
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- * this software without specific prior written permission.
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- *
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- * Alternatively, this software may be distributed under the terms of the
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- * GNU General Public License ("GPL") version 2 as published by the Free
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- * Software Foundation.
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- *
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- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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- * POSSIBILITY OF SUCH DAMAGE.
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- */
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-
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-#include "core.h"
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-#include "ref.h"
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-
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-/**
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- * struct reference - TIPC socket reference entry
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- * @tsk: pointer to socket associated with reference entry
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- * @ref: reference value for socket (combines instance & array index info)
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- */
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-struct reference {
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- struct tipc_sock *tsk;
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- u32 ref;
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-};
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-
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-/**
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- * struct tipc_ref_table - table of TIPC socket reference entries
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- * @entries: pointer to array of reference entries
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- * @capacity: array index of first unusable entry
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- * @init_point: array index of first uninitialized entry
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- * @first_free: array index of first unused socket reference entry
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- * @last_free: array index of last unused socket reference entry
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- * @index_mask: bitmask for array index portion of reference values
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- * @start_mask: initial value for instance value portion of reference values
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- */
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-struct ref_table {
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- struct reference *entries;
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- u32 capacity;
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- u32 init_point;
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- u32 first_free;
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- u32 last_free;
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- u32 index_mask;
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- u32 start_mask;
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-};
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-
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-/*
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- * Socket reference table consists of 2**N entries.
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- *
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- * State Socket ptr Reference
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- * ----- ---------- ---------
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- * In use non-NULL XXXX|own index
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- * (XXXX changes each time entry is acquired)
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- * Free NULL YYYY|next free index
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- * (YYYY is one more than last used XXXX)
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- * Uninitialized NULL 0
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- *
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- * Entry 0 is not used; this allows index 0 to denote the end of the free list.
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- *
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- * Note that a reference value of 0 does not necessarily indicate that an
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- * entry is uninitialized, since the last entry in the free list could also
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- * have a reference value of 0 (although this is unlikely).
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- */
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-
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-static struct ref_table tipc_ref_table;
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-
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-static DEFINE_RWLOCK(ref_table_lock);
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-
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-/**
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- * tipc_ref_table_init - create reference table for sockets
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- */
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-int tipc_ref_table_init(u32 requested_size, u32 start)
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-{
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- struct reference *table;
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- u32 actual_size;
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-
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- /* account for unused entry, then round up size to a power of 2 */
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-
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- requested_size++;
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- for (actual_size = 16; actual_size < requested_size; actual_size <<= 1)
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- /* do nothing */ ;
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-
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- /* allocate table & mark all entries as uninitialized */
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- table = vzalloc(actual_size * sizeof(struct reference));
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- if (table == NULL)
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- return -ENOMEM;
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-
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- tipc_ref_table.entries = table;
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- tipc_ref_table.capacity = requested_size;
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- tipc_ref_table.init_point = 1;
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- tipc_ref_table.first_free = 0;
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- tipc_ref_table.last_free = 0;
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- tipc_ref_table.index_mask = actual_size - 1;
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- tipc_ref_table.start_mask = start & ~tipc_ref_table.index_mask;
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-
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- return 0;
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-}
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-
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-/**
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- * tipc_ref_table_stop - destroy reference table for sockets
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- */
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-void tipc_ref_table_stop(void)
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-{
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- if (!tipc_ref_table.entries)
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- return;
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- vfree(tipc_ref_table.entries);
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- tipc_ref_table.entries = NULL;
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-}
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-
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-/* tipc_ref_acquire - create reference to a socket
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- *
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- * Register an socket pointer in the reference table.
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- * Returns a unique reference value that is used from then on to retrieve the
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- * socket pointer, or to determine if the socket has been deregistered.
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- */
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-u32 tipc_ref_acquire(struct tipc_sock *tsk)
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-{
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- u32 index;
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- u32 index_mask;
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- u32 next_plus_upper;
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- u32 ref = 0;
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- struct reference *entry;
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-
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- if (unlikely(!tsk)) {
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- pr_err("Attempt to acquire ref. to non-existent obj\n");
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- return 0;
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- }
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- if (unlikely(!tipc_ref_table.entries)) {
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- pr_err("Ref. table not found in acquisition attempt\n");
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- return 0;
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- }
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-
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- /* Take a free entry, if available; otherwise initialize a new one */
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- write_lock_bh(&ref_table_lock);
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- index = tipc_ref_table.first_free;
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- entry = &tipc_ref_table.entries[index];
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-
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- if (likely(index)) {
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- index = tipc_ref_table.first_free;
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- entry = &(tipc_ref_table.entries[index]);
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- index_mask = tipc_ref_table.index_mask;
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- next_plus_upper = entry->ref;
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- tipc_ref_table.first_free = next_plus_upper & index_mask;
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- ref = (next_plus_upper & ~index_mask) + index;
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- entry->tsk = tsk;
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- } else if (tipc_ref_table.init_point < tipc_ref_table.capacity) {
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- index = tipc_ref_table.init_point++;
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- entry = &(tipc_ref_table.entries[index]);
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- ref = tipc_ref_table.start_mask + index;
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- }
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-
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- if (ref) {
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- entry->ref = ref;
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- entry->tsk = tsk;
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- }
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- write_unlock_bh(&ref_table_lock);
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- return ref;
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-}
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-
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-/* tipc_ref_discard - invalidate reference to an socket
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- *
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- * Disallow future references to an socket and free up the entry for re-use.
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- */
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-void tipc_ref_discard(u32 ref)
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-{
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- struct reference *entry;
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- u32 index;
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- u32 index_mask;
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-
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- if (unlikely(!tipc_ref_table.entries)) {
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- pr_err("Ref. table not found during discard attempt\n");
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- return;
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- }
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-
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- index_mask = tipc_ref_table.index_mask;
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- index = ref & index_mask;
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- entry = &(tipc_ref_table.entries[index]);
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-
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- write_lock_bh(&ref_table_lock);
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-
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- if (unlikely(!entry->tsk)) {
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- pr_err("Attempt to discard ref. to non-existent socket\n");
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- goto exit;
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- }
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- if (unlikely(entry->ref != ref)) {
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- pr_err("Attempt to discard non-existent reference\n");
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- goto exit;
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- }
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-
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- /*
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- * Mark entry as unused; increment instance part of entry's reference
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- * to invalidate any subsequent references
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- */
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- entry->tsk = NULL;
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- entry->ref = (ref & ~index_mask) + (index_mask + 1);
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-
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- /* Append entry to free entry list */
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- if (unlikely(tipc_ref_table.first_free == 0))
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- tipc_ref_table.first_free = index;
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- else
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- tipc_ref_table.entries[tipc_ref_table.last_free].ref |= index;
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- tipc_ref_table.last_free = index;
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-exit:
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- write_unlock_bh(&ref_table_lock);
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-}
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-
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-/* tipc_sk_get - find referenced socket and return pointer to it
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- */
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-struct tipc_sock *tipc_sk_get(u32 ref)
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-{
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- struct reference *entry;
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- struct tipc_sock *tsk;
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-
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- if (unlikely(!tipc_ref_table.entries))
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- return NULL;
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- read_lock_bh(&ref_table_lock);
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- entry = &tipc_ref_table.entries[ref & tipc_ref_table.index_mask];
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- tsk = entry->tsk;
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- if (likely(tsk && (entry->ref == ref)))
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- sock_hold(&tsk->sk);
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- else
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- tsk = NULL;
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- read_unlock_bh(&ref_table_lock);
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- return tsk;
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-}
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-
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-/* tipc_sk_get_next - lock & return next socket after referenced one
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-*/
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-struct tipc_sock *tipc_sk_get_next(u32 *ref)
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-{
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- struct reference *entry;
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- struct tipc_sock *tsk = NULL;
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- uint index = *ref & tipc_ref_table.index_mask;
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-
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- read_lock_bh(&ref_table_lock);
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- while (++index < tipc_ref_table.capacity) {
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- entry = &tipc_ref_table.entries[index];
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- if (!entry->tsk)
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- continue;
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- tsk = entry->tsk;
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- sock_hold(&tsk->sk);
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- *ref = entry->ref;
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- break;
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- }
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- read_unlock_bh(&ref_table_lock);
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- return tsk;
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-}
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