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@@ -24,200 +24,7 @@
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#include <asm/mmu_context.h>
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-#ifdef CONFIG_PPC_ICSWX
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-/*
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- * The processor and its L2 cache cause the icswx instruction to
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- * generate a COP_REQ transaction on PowerBus. The transaction has
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- * no address, and the processor does not perform an MMU access
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- * to authenticate the transaction. The command portion of the
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- * PowerBus COP_REQ transaction includes the LPAR_ID (LPID) and
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- * the coprocessor Process ID (PID), which the coprocessor compares
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- * to the authorized LPID and PID held in the coprocessor, to determine
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- * if the process is authorized to generate the transaction.
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- * The data of the COP_REQ transaction is 128-byte or less and is
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- * placed in cacheable memory on a 128-byte cache line boundary.
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- *
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- * The task to use a coprocessor should use use_cop() to allocate
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- * a coprocessor PID before executing icswx instruction. use_cop()
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- * also enables the coprocessor context switching. Drop_cop() is
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- * used to free the coprocessor PID.
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- *
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- * Example:
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- * Host Fabric Interface (HFI) is a PowerPC network coprocessor.
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- * Each HFI have multiple windows. Each HFI window serves as a
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- * network device sending to and receiving from HFI network.
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- * HFI immediate send function uses icswx instruction. The immediate
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- * send function allows small (single cache-line) packets be sent
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- * without using the regular HFI send FIFO and doorbell, which are
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- * much slower than immediate send.
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- *
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- * For each task intending to use HFI immediate send, the HFI driver
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- * calls use_cop() to obtain a coprocessor PID for the task.
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- * The HFI driver then allocate a free HFI window and save the
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- * coprocessor PID to the HFI window to allow the task to use the
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- * HFI window.
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- *
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- * The HFI driver repeatedly creates immediate send packets and
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- * issues icswx instruction to send data through the HFI window.
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- * The HFI compares the coprocessor PID in the CPU PID register
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- * to the PID held in the HFI window to determine if the transaction
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- * is allowed.
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- *
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- * When the task to release the HFI window, the HFI driver calls
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- * drop_cop() to release the coprocessor PID.
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- */
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-
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-#define COP_PID_NONE 0
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-#define COP_PID_MIN (COP_PID_NONE + 1)
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-#define COP_PID_MAX (0xFFFF)
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-
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-static DEFINE_SPINLOCK(mmu_context_acop_lock);
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-static DEFINE_IDA(cop_ida);
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-
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-void switch_cop(struct mm_struct *next)
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-{
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- mtspr(SPRN_PID, next->context.cop_pid);
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- mtspr(SPRN_ACOP, next->context.acop);
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-}
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-
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-static int new_cop_pid(struct ida *ida, int min_id, int max_id,
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- spinlock_t *lock)
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-{
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- int index;
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- int err;
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-
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-again:
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- if (!ida_pre_get(ida, GFP_KERNEL))
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- return -ENOMEM;
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-
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- spin_lock(lock);
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- err = ida_get_new_above(ida, min_id, &index);
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- spin_unlock(lock);
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-
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- if (err == -EAGAIN)
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- goto again;
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- else if (err)
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- return err;
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-
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- if (index > max_id) {
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- spin_lock(lock);
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- ida_remove(ida, index);
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- spin_unlock(lock);
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- return -ENOMEM;
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- }
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-
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- return index;
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-}
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-
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-static void sync_cop(void *arg)
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-{
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- struct mm_struct *mm = arg;
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-
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- if (mm == current->active_mm)
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- switch_cop(current->active_mm);
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-}
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-
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-/**
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- * Start using a coprocessor.
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- * @acop: mask of coprocessor to be used.
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- * @mm: The mm the coprocessor to associate with. Most likely current mm.
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- *
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- * Return a positive PID if successful. Negative errno otherwise.
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- * The returned PID will be fed to the coprocessor to determine if an
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- * icswx transaction is authenticated.
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- */
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-int use_cop(unsigned long acop, struct mm_struct *mm)
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-{
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- int ret;
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-
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- if (!cpu_has_feature(CPU_FTR_ICSWX))
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- return -ENODEV;
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-
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- if (!mm || !acop)
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- return -EINVAL;
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-
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- /* The page_table_lock ensures mm_users won't change under us */
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- spin_lock(&mm->page_table_lock);
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- spin_lock(mm->context.cop_lockp);
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-
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- if (mm->context.cop_pid == COP_PID_NONE) {
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- ret = new_cop_pid(&cop_ida, COP_PID_MIN, COP_PID_MAX,
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- &mmu_context_acop_lock);
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- if (ret < 0)
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- goto out;
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-
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- mm->context.cop_pid = ret;
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- }
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- mm->context.acop |= acop;
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-
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- sync_cop(mm);
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-
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- /*
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- * If this is a threaded process then there might be other threads
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- * running. We need to send an IPI to force them to pick up any
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- * change in PID and ACOP.
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- */
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- if (atomic_read(&mm->mm_users) > 1)
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- smp_call_function(sync_cop, mm, 1);
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-
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- ret = mm->context.cop_pid;
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-
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-out:
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- spin_unlock(mm->context.cop_lockp);
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- spin_unlock(&mm->page_table_lock);
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-
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- return ret;
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-}
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-EXPORT_SYMBOL_GPL(use_cop);
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-
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-/**
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- * Stop using a coprocessor.
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- * @acop: mask of coprocessor to be stopped.
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- * @mm: The mm the coprocessor associated with.
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- */
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-void drop_cop(unsigned long acop, struct mm_struct *mm)
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-{
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- int free_pid = COP_PID_NONE;
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-
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- if (!cpu_has_feature(CPU_FTR_ICSWX))
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- return;
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-
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- if (WARN_ON_ONCE(!mm))
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- return;
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-
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- /* The page_table_lock ensures mm_users won't change under us */
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- spin_lock(&mm->page_table_lock);
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- spin_lock(mm->context.cop_lockp);
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-
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- mm->context.acop &= ~acop;
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-
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- if ((!mm->context.acop) && (mm->context.cop_pid != COP_PID_NONE)) {
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- free_pid = mm->context.cop_pid;
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- mm->context.cop_pid = COP_PID_NONE;
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- }
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-
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- sync_cop(mm);
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-
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- /*
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- * If this is a threaded process then there might be other threads
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- * running. We need to send an IPI to force them to pick up any
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- * change in PID and ACOP.
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- */
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- if (atomic_read(&mm->mm_users) > 1)
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- smp_call_function(sync_cop, mm, 1);
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-
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- if (free_pid != COP_PID_NONE) {
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- spin_lock(&mmu_context_acop_lock);
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- ida_remove(&cop_ida, free_pid);
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- spin_unlock(&mmu_context_acop_lock);
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- }
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-
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- spin_unlock(mm->context.cop_lockp);
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- spin_unlock(&mm->page_table_lock);
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-}
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-EXPORT_SYMBOL_GPL(drop_cop);
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-
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-#endif /* CONFIG_PPC_ICSWX */
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+#include "icswx.h"
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static DEFINE_SPINLOCK(mmu_context_lock);
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static DEFINE_IDA(mmu_context_ida);
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