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Commit ecdaf2b5 authored by Jack Steiner's avatar Jack Steiner Committed by Linus Torvalds
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sgi-gru: restructure the GRU vtop functions 



Restructure the GRU vtop functions in preparation for future changes.
This patch simply moves code around & does not change the algorithm.

Signed-off-by: default avatarJack Steiner <steiner@sgi.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 87419412

drivers/misc/sgi-gru/grufault.c

+44 −24
Original line number Diff line number Diff line
@@ -267,6 +267,44 @@ static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr, 
	return 1;

}



static int gru_vtop(struct gru_thread_state *gts, unsigned long vaddr,

		    int write, int atomic, unsigned long *gpa, int *pageshift)

{

	struct mm_struct *mm = gts->ts_mm;

	struct vm_area_struct *vma;

	unsigned long paddr;

	int ret, ps;



	vma = find_vma(mm, vaddr);

	if (!vma)

		goto inval;



	/*

	 * Atomic lookup is faster & usually works even if called in non-atomic

	 * context.

	 */

	rmb();	/* Must/check ms_range_active before loading PTEs */

	ret = atomic_pte_lookup(vma, vaddr, write, &paddr, &ps);

	if (ret) {

		if (atomic)

			goto upm;

		if (non_atomic_pte_lookup(vma, vaddr, write, &paddr, &ps))

			goto inval;

	}

	if (is_gru_paddr(paddr))

		goto inval;

	paddr = paddr & ~((1UL << ps) - 1);

	*gpa = uv_soc_phys_ram_to_gpa(paddr);

	*pageshift = ps;

	return 0;



inval:

	return -1;

upm:

	return -2;

}





/*

 * Drop a TLB entry into the GRU. The fault is described by info in an TFH.

 *	Input:
@@ -281,10 +319,8 @@ static int gru_try_dropin(struct gru_thread_state *gts, 
			  struct gru_tlb_fault_handle *tfh,

			  unsigned long __user *cb)

{

	struct mm_struct *mm = gts->ts_mm;

	struct vm_area_struct *vma;

	int pageshift, asid, write, ret;

	unsigned long paddr, gpa, vaddr;

	int pageshift = 0, asid, write, ret, atomic = !cb;

	unsigned long gpa = 0, vaddr = 0;



	/*

	 * NOTE: The GRU contains magic hardware that eliminates races between
@@ -318,28 +354,12 @@ static int gru_try_dropin(struct gru_thread_state *gts, 
	if (atomic_read(&gts->ts_gms->ms_range_active))

		goto failactive;



	vma = find_vma(mm, vaddr);

	if (!vma)

	ret = gru_vtop(gts, vaddr, write, atomic, &gpa, &pageshift);

	if (ret == -1)

		goto failinval;



	/*

	 * Atomic lookup is faster & usually works even if called in non-atomic

	 * context.

	 */

	rmb();	/* Must/check ms_range_active before loading PTEs */

	ret = atomic_pte_lookup(vma, vaddr, write, &paddr, &pageshift);

	if (ret) {

		if (!cb)

	if (ret == -2)

		goto failupm;

		if (non_atomic_pte_lookup(vma, vaddr, write, &paddr,

					  &pageshift))

			goto failinval;

	}

	if (is_gru_paddr(paddr))

		goto failinval;



	paddr = paddr & ~((1UL << pageshift) - 1);

	gpa = uv_soc_phys_ram_to_gpa(paddr);

	gru_cb_set_istatus_active(cb);

	tfh_write_restart(tfh, gpa, GAA_RAM, vaddr, asid, write,

			  GRU_PAGESIZE(pageshift));