iommu-helper: use bitmap library

Use bitmap library and kill some unused iommu helper functions.

1. s/iommu_area_free/bitmap_clear/

2. s/iommu_area_reserve/bitmap_set/

3. Use bitmap_find_next_zero_area instead of find_next_zero_area

  This cannot be simple substitution because find_next_zero_area
  doesn't check the last bit of the limit in bitmap

4. Remove iommu_area_free, iommu_area_reserve, and find_next_zero_area

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

7 files changed, 21 insertions, 64 deletions

diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index fd51578e29dd..5547ae6e6b0b 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -30,7 +30,7 @@
 #include <linux/spinlock.h>
 #include <linux/string.h>
 #include <linux/dma-mapping.h>
-#include <linux/bitops.h>
+#include <linux/bitmap.h>
 #include <linux/iommu-helper.h>
 #include <linux/crash_dump.h>
 #include <asm/io.h>
@@ -251,7 +251,7 @@ static void __iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr,
         }
 
         ppc_md.tce_free(tbl, entry, npages);
-        iommu_area_free(tbl->it_map, free_entry, npages);
+        bitmap_clear(tbl->it_map, free_entry, npages);
 }
 
 static void iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr,
diff --git a/arch/sparc/kernel/iommu.c b/arch/sparc/kernel/iommu.c
index 7690cc219ecc..5fad94950e76 100644
--- a/arch/sparc/kernel/iommu.c
+++ b/arch/sparc/kernel/iommu.c
@@ -11,6 +11,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/errno.h>
 #include <linux/iommu-helper.h>
+#include <linux/bitmap.h>
 
 #ifdef CONFIG_PCI
 #include <linux/pci.h>
@@ -169,7 +170,7 @@ void iommu_range_free(struct iommu *iommu, dma_addr_t dma_addr, unsigned long np
 
         entry = (dma_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT;
 
-        iommu_area_free(arena->map, entry, npages);
+        bitmap_clear(arena->map, entry, npages);
 }
 
 int iommu_table_init(struct iommu *iommu, int tsbsize,
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index b990b5cc9541..23824fef789c 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -19,7 +19,7 @@
 
 #include <linux/pci.h>
 #include <linux/gfp.h>
-#include <linux/bitops.h>
+#include <linux/bitmap.h>
 #include <linux/debugfs.h>
 #include <linux/scatterlist.h>
 #include <linux/dma-mapping.h>
@@ -1162,7 +1162,7 @@ static void dma_ops_free_addresses(struct dma_ops_domain *dom,
 
         address = (address % APERTURE_RANGE_SIZE) >> PAGE_SHIFT;
 
-        iommu_area_free(range->bitmap, address, pages);
+        bitmap_clear(range->bitmap, address, pages);
 
 }
 
diff --git a/arch/x86/kernel/pci-calgary_64.c b/arch/x86/kernel/pci-calgary_64.c
index c563e4c8ff39..2bbde6078143 100644
--- a/arch/x86/kernel/pci-calgary_64.c
+++ b/arch/x86/kernel/pci-calgary_64.c
@@ -31,7 +31,7 @@
 #include <linux/string.h>
 #include <linux/crash_dump.h>
 #include <linux/dma-mapping.h>
-#include <linux/bitops.h>
+#include <linux/bitmap.h>
 #include <linux/pci_ids.h>
 #include <linux/pci.h>
 #include <linux/delay.h>
@@ -212,7 +212,7 @@ static void iommu_range_reserve(struct iommu_table *tbl,
 
         spin_lock_irqsave(&tbl->it_lock, flags);
 
-        iommu_area_reserve(tbl->it_map, index, npages);
+        bitmap_set(tbl->it_map, index, npages);
 
         spin_unlock_irqrestore(&tbl->it_lock, flags);
 }
@@ -303,7 +303,7 @@ static void iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr,
 
         spin_lock_irqsave(&tbl->it_lock, flags);
 
-        iommu_area_free(tbl->it_map, entry, npages);
+        bitmap_clear(tbl->it_map, entry, npages);
 
         spin_unlock_irqrestore(&tbl->it_lock, flags);
 }
diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index 56c0e730d3fe..34de53b46f87 100644
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -23,7 +23,7 @@
 #include <linux/module.h>
 #include <linux/topology.h>
 #include <linux/interrupt.h>
-#include <linux/bitops.h>
+#include <linux/bitmap.h>
 #include <linux/kdebug.h>
 #include <linux/scatterlist.h>
 #include <linux/iommu-helper.h>
@@ -126,7 +126,7 @@ static void free_iommu(unsigned long offset, int size)
         unsigned long flags;
 
         spin_lock_irqsave(&iommu_bitmap_lock, flags);
-        iommu_area_free(iommu_gart_bitmap, offset, size);
+        bitmap_clear(iommu_gart_bitmap, offset, size);
         if (offset >= next_bit)
                 next_bit = offset + size;
         spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
@@ -792,7 +792,7 @@ int __init gart_iommu_init(void)
          * Out of IOMMU space handling.
          * Reserve some invalid pages at the beginning of the GART.
          */
-        iommu_area_reserve(iommu_gart_bitmap, 0, EMERGENCY_PAGES);
+        bitmap_set(iommu_gart_bitmap, 0, EMERGENCY_PAGES);
 
         pr_info("PCI-DMA: Reserving %luMB of IOMMU area in the AGP aperture\n",
                iommu_size >> 20);
diff --git a/include/linux/iommu-helper.h b/include/linux/iommu-helper.h
index 3b068e5b5671..64d1b638745d 100644
--- a/include/linux/iommu-helper.h
+++ b/include/linux/iommu-helper.h
@@ -14,14 +14,11 @@ static inline unsigned long iommu_device_max_index(unsigned long size,
 extern int iommu_is_span_boundary(unsigned int index, unsigned int nr,
                                   unsigned long shift,
                                   unsigned long boundary_size);
-extern void iommu_area_reserve(unsigned long *map, unsigned long i, int len);
 extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
                                       unsigned long start, unsigned int nr,
                                       unsigned long shift,
                                       unsigned long boundary_size,
                                       unsigned long align_mask);
-extern void iommu_area_free(unsigned long *map, unsigned long start,
-                            unsigned int nr);
 
 extern unsigned long iommu_num_pages(unsigned long addr, unsigned long len,
                                      unsigned long io_page_size);
diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c
index 75dbda03f4fb..c0251f4ad08b 100644
--- a/lib/iommu-helper.c
+++ b/lib/iommu-helper.c
@@ -3,41 +3,7 @@
  */
 
 #include <linux/module.h>
-#include <linux/bitops.h>
-
-static unsigned long find_next_zero_area(unsigned long *map,
-                                         unsigned long size,
-                                         unsigned long start,
-                                         unsigned int nr,
-                                         unsigned long align_mask)
-{
-        unsigned long index, end, i;
-again:
-        index = find_next_zero_bit(map, size, start);
-
-        /* Align allocation */
-        index = (index + align_mask) & ~align_mask;
-
-        end = index + nr;
-        if (end >= size)
-                return -1;
-        for (i = index; i < end; i++) {
-                if (test_bit(i, map)) {
-                        start = i+1;
-                        goto again;
-                }
-        }
-        return index;
-}
-
-void iommu_area_reserve(unsigned long *map, unsigned long i, int len)
-{
-        unsigned long end = i + len;
-        while (i < end) {
-                __set_bit(i, map);
-                i++;
-        }
-}
+#include <linux/bitmap.h>
 
 int iommu_is_span_boundary(unsigned int index, unsigned int nr,
                            unsigned long shift,
@@ -55,31 +21,24 @@ unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
                                unsigned long align_mask)
 {
         unsigned long index;
+
+        /* We don't want the last of the limit */
+        size -= 1;
 again:
-        index = find_next_zero_area(map, size, start, nr, align_mask);
-        if (index != -1) {
+        index = bitmap_find_next_zero_area(map, size, start, nr, align_mask);
+        if (index < size) {
                 if (iommu_is_span_boundary(index, nr, shift, boundary_size)) {
                         /* we could do more effectively */
                         start = index + 1;
                         goto again;
                 }
-                iommu_area_reserve(map, index, nr);
+                bitmap_set(map, index, nr);
+                return index;
         }
-        return index;
+        return -1;
 }
 EXPORT_SYMBOL(iommu_area_alloc);
 
-void iommu_area_free(unsigned long *map, unsigned long start, unsigned int nr)
-{
-        unsigned long end = start + nr;
-
-        while (start < end) {
-                __clear_bit(start, map);
-                start++;
-        }
-}
-EXPORT_SYMBOL(iommu_area_free);
-
 unsigned long iommu_num_pages(unsigned long addr, unsigned long len,
                               unsigned long io_page_size)
 {