From: Konrad Rzeszutek <konrad@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
---
include/linux/swiotlb.h | 5 +-
lib/Makefile | 2 +-
lib/swiotlb-core.c | 957 +++++++++++++++++++++++++++++++++++++++++++++++
lib/swiotlb.c | 957 -----------------------------------------------
4 files changed, 961 insertions(+), 960 deletions(-)
create mode 100644 lib/swiotlb-core.c
delete mode 100644 lib/swiotlb.c
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index af66473..6ab9b7c 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -22,6 +22,7 @@ extern int swiotlb_force;
*/
#define IO_TLB_SHIFT 11
+/* swiotlb-core.c */
extern void swiotlb_init(int verbose);
#ifdef CONFIG_SWIOTLB
extern void __init swiotlb_free(void);
@@ -30,8 +31,8 @@ static inline void swiotlb_free(void) { }
#endif
extern void swiotlb_print_info(void);
-/* Internal book-keeping functions. Must be linked against the library
- * to take advantage of them.*/
+/* swiotlb-core.c: Internal book-keeping functions.
+ * Must be linked against the library to take advantage of them.*/
#ifdef CONFIG_SWIOTLB
/*
* Enumeration for sync targets
diff --git a/lib/Makefile b/lib/Makefile
index 3b0b4a6..40728c5 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -78,7 +78,7 @@ obj-$(CONFIG_TEXTSEARCH_FSM) += ts_fsm.o
obj-$(CONFIG_SMP) += percpu_counter.o
obj-$(CONFIG_AUDIT_GENERIC) += audit.o
-obj-$(CONFIG_SWIOTLB) += swiotlb.o
+obj-$(CONFIG_SWIOTLB) += swiotlb-core.o swiotlb.o
obj-$(CONFIG_IOMMU_HELPER) += iommu-helper.o
obj-$(CONFIG_FAULT_INJECTION) += fault-inject.o
diff --git a/lib/swiotlb-core.c b/lib/swiotlb-core.c
new file mode 100644
index 0000000..c982d33
--- /dev/null
+++ b/lib/swiotlb-core.c
@@ -0,0 +1,957 @@
+/*
+ * Dynamic DMA mapping support.
+ *
+ * This implementation is a fallback for platforms that do not support
+ * I/O TLBs (aka DMA address translation hardware).
+ * Copyright (C) 2000 Asit Mallick <Asit.K.Mallick@xxxxxxxxx>
+ * Copyright (C) 2000 Goutham Rao <goutham.rao@xxxxxxxxx>
+ * Copyright (C) 2000, 2003 Hewlett-Packard Co
+ * David Mosberger-Tang <davidm@xxxxxxxxxx>
+ *
+ * 03/05/07 davidm Switch from PCI-DMA to generic device DMA API.
+ * 00/12/13 davidm Rename to swiotlb.c and add mark_clean() to avoid
+ * unnecessary i-cache flushing.
+ * 04/07/.. ak Better overflow handling. Assorted fixes.
+ * 05/09/10 linville Add support for syncing ranges, support syncing for
+ * DMA_BIDIRECTIONAL mappings, miscellaneous cleanup.
+ * 08/12/11 beckyb Add highmem support
+ */
+
+#include <linux/cache.h>
+#include <linux/dma-mapping.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/swiotlb.h>
+#include <linux/pfn.h>
+#include <linux/types.h>
+#include <linux/ctype.h>
+#include <linux/highmem.h>
+
+#include <linux/io.h>
+#include <asm/dma.h>
+#include <linux/scatterlist.h>
+
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/iommu-helper.h>
+
+#define OFFSET(val, align) ((unsigned long) ((val) & ((align) - 1)))
+
+#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))
+
+/*
+ * Minimum IO TLB size to bother booting with. Systems with mainly
+ * 64bit capable cards will only lightly use the swiotlb. If we can't
+ * allocate a contiguous 1MB, we're probably in trouble anyway.
+ */
+#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
+
+int swiotlb_force;
+
+/*
+ * Used to do a quick range check in do_unmap_single and
+ * do_sync_single_*, to see if the memory was in fact allocated by this
+ * API.
+ */
+char *io_tlb_start, *io_tlb_end;
+
+/*
+ * The number of IO TLB blocks (in groups of 64) betweeen io_tlb_start and
+ * io_tlb_end. This is command line adjustable via setup_io_tlb_npages.
+ */
+unsigned long io_tlb_nslabs;
+
+/*
+ * When the IOMMU overflows we return a fallback buffer. This sets the size.
+ */
+unsigned long io_tlb_overflow = 32*1024;
+
+void *io_tlb_overflow_buffer;
+
+/*
+ * This is a free list describing the number of free entries available from
+ * each index
+ */
+static unsigned int *io_tlb_list;
+static unsigned int io_tlb_index;
+
+/*
+ * We need to save away the original address corresponding to a mapped entry
+ * for the sync operations.
+ */
+static phys_addr_t *io_tlb_orig_addr;
+
+/*
+ * Protect the above data structures in the map and unmap calls
+ */
+static DEFINE_SPINLOCK(io_tlb_lock);
+
+static int late_alloc;
+
+static int __init
+setup_io_tlb_npages(char *str)
+{
+ int get_value(const char *token, char *str, char **endp)
+ {
+ ssize_t len;
+ int val = 0;
+
+ len = strlen(token);
+ if (!strncmp(str, token, len)) {
+ str += len;
+ if (*str == '=')
+ ++str;
+ if (*str != '\0')
+ val = simple_strtoul(str, endp, 0);
+ }
+ *endp = str;
+ return val;
+ }
+
+ int val;
+
+ while (*str) {
+ /* The old syntax */
+ if (isdigit(*str)) {
+ io_tlb_nslabs = simple_strtoul(str, &str, 0);
+ /* avoid tail segment of size < IO_TLB_SEGSIZE */
+ io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
+ }
+ if (!strncmp(str, "force", 5))
+ swiotlb_force = 1;
+ /* The new syntax: swiotlb=nslabs=16384,overflow=32768,force */
+ val = get_value("nslabs", str, &str);
+ if (val)
+ io_tlb_nslabs = ALIGN(val, IO_TLB_SEGSIZE);
+
+ val = get_value("overflow", str, &str);
+ if (val)
+ io_tlb_overflow = val;
+ str = strpbrk(str, ",");
+ if (!str)
+ break;
+ str++; /* skip ',' */
+ }
+ return 1;
+}
+__setup("swiotlb=", setup_io_tlb_npages);
+
+/* Note that this doesn't work with highmem page */
+static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
+ volatile void *address)
+{
+ return phys_to_dma(hwdev, virt_to_phys(address));
+}
+
+void swiotlb_print_info(void)
+{
+ unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT;
+ phys_addr_t pstart, pend;
+
+ pstart = virt_to_phys(io_tlb_start);
+ pend = virt_to_phys(io_tlb_end);
+
+ printk(KERN_INFO "DMA: Placing %luMB software IO TLB between %p - %p\n",
+ bytes >> 20, io_tlb_start, io_tlb_end);
+ printk(KERN_INFO "DMA: software IO TLB at phys %#llx - %#llx\n",
+ (unsigned long long)pstart,
+ (unsigned long long)pend);
+}
+
+/*
+ * Statically reserve bounce buffer space and initialize bounce buffer data
+ * structures for the software IO TLB used to implement the DMA API.
+ */
+void __init
+swiotlb_init_early(size_t default_size, int verbose)
+{
+ unsigned long i, bytes;
+
+ if (!io_tlb_nslabs) {
+ io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
+ io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
+ }
+
+ bytes = io_tlb_nslabs << IO_TLB_SHIFT;
+
+ /*
+ * Get IO TLB memory from the low pages
+ */
+ io_tlb_start = alloc_bootmem_low_pages(bytes);
+ if (!io_tlb_start)
+ panic("DMA: Cannot allocate SWIOTLB buffer");
+ io_tlb_end = io_tlb_start + bytes;
+
+ /*
+ * Allocate and initialize the free list array. This array is used
+ * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
+ * between io_tlb_start and io_tlb_end.
+ */
+ io_tlb_list = alloc_bootmem(io_tlb_nslabs * sizeof(int));
+ for (i = 0; i < io_tlb_nslabs; i++)
+ io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
+ io_tlb_index = 0;
+ io_tlb_orig_addr = alloc_bootmem(io_tlb_nslabs * sizeof(phys_addr_t));
+
+ /*
+ * Get the overflow emergency buffer
+ */
+ io_tlb_overflow_buffer = alloc_bootmem_low(io_tlb_overflow);
+ if (!io_tlb_overflow_buffer)
+ panic("DMA: Cannot allocate SWIOTLB overflow buffer!\n");
+ if (verbose)
+ swiotlb_print_info();
+}
+
+void __init
+swiotlb_init(int verbose)
+{
+ swiotlb_init_early(64 * (1<<20), verbose); /* default to 64MB */
+}
+
+/*
+ * Systems with larger DMA zones (those that don't support ISA) can
+ * initialize the swiotlb later using the slab allocator if needed.
+ * This should be just like above, but with some error catching.
+ */
+int
+swiotlb_init_late(size_t default_size)
+{
+ unsigned long i, bytes, req_nslabs = io_tlb_nslabs;
+ unsigned int order;
+
+ if (!io_tlb_nslabs) {
+ io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
+ io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
+ }
+
+ /*
+ * Get IO TLB memory from the low pages
+ */
+ order = get_order(io_tlb_nslabs << IO_TLB_SHIFT);
+ io_tlb_nslabs = SLABS_PER_PAGE << order;
+ bytes = io_tlb_nslabs << IO_TLB_SHIFT;
+
+ while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
+ io_tlb_start = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
+ order);
+ if (io_tlb_start)
+ break;
+ order--;
+ }
+
+ if (!io_tlb_start)
+ goto cleanup1;
+
+ if (order != get_order(bytes)) {
+ printk(KERN_WARNING "DMA: Warning: only able to allocate %ld MB"
+ " for software IO TLB\n", (PAGE_SIZE << order) >> 20);
+ io_tlb_nslabs = SLABS_PER_PAGE << order;
+ bytes = io_tlb_nslabs << IO_TLB_SHIFT;
+ }
+ io_tlb_end = io_tlb_start + bytes;
+ memset(io_tlb_start, 0, bytes);
+
+ /*
+ * Allocate and initialize the free list array. This array is used
+ * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
+ * between io_tlb_start and io_tlb_end.
+ */
+ io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL,
+ get_order(io_tlb_nslabs * sizeof(int)));
+ if (!io_tlb_list)
+ goto cleanup2;
+
+ for (i = 0; i < io_tlb_nslabs; i++)
+ io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
+ io_tlb_index = 0;
+
+ io_tlb_orig_addr = (phys_addr_t *) __get_free_pages(GFP_KERNEL,
+ get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
+ if (!io_tlb_orig_addr)
+ goto cleanup3;
+
+ memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(phys_addr_t));
+
+ /*
+ * Get the overflow emergency buffer
+ */
+ io_tlb_overflow_buffer = (void *)__get_free_pages(GFP_DMA,
+ get_order(io_tlb_overflow));
+ if (!io_tlb_overflow_buffer)
+ goto cleanup4;
+
+ swiotlb_print_info();
+
+ late_alloc = 1;
+
+ return 0;
+
+cleanup4:
+ free_pages((unsigned long)io_tlb_orig_addr,
+ get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
+ io_tlb_orig_addr = NULL;
+cleanup3:
+ free_pages((unsigned long)io_tlb_list,
+ get_order(io_tlb_nslabs * sizeof(int)));
+ io_tlb_list = NULL;
+cleanup2:
+ io_tlb_end = NULL;
+ free_pages((unsigned long)io_tlb_start, order);
+ io_tlb_start = NULL;
+cleanup1:
+ io_tlb_nslabs = req_nslabs;
+ return -ENOMEM;
+}
+
+void __init swiotlb_free(void)
+{
+ if (!io_tlb_overflow_buffer)
+ return;
+
+ if (late_alloc) {
+ free_pages((unsigned long)io_tlb_overflow_buffer,
+ get_order(io_tlb_overflow));
+ free_pages((unsigned long)io_tlb_orig_addr,
+ get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
+ free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
+ sizeof(int)));
+ free_pages((unsigned long)io_tlb_start,
+ get_order(io_tlb_nslabs << IO_TLB_SHIFT));
+ } else {
+ free_bootmem_late(__pa(io_tlb_overflow_buffer),
+ io_tlb_overflow);
+ free_bootmem_late(__pa(io_tlb_orig_addr),
+ io_tlb_nslabs * sizeof(phys_addr_t));
+ free_bootmem_late(__pa(io_tlb_list),
+ io_tlb_nslabs * sizeof(int));
+ free_bootmem_late(__pa(io_tlb_start),
+ io_tlb_nslabs << IO_TLB_SHIFT);
+ }
+}
+
+int is_swiotlb_buffer(phys_addr_t paddr)
+{
+ return paddr >= virt_to_phys(io_tlb_start) &&
+ paddr < virt_to_phys(io_tlb_end);
+}
+
+/*
+ * Bounce: copy the swiotlb buffer back to the original dma location
+ */
+void swiotlb_bounce(phys_addr_t phys, char *dma_addr, size_t size,
+ enum dma_data_direction dir)
+{
+ unsigned long pfn = PFN_DOWN(phys);
+
+ if (PageHighMem(pfn_to_page(pfn))) {
+ /* The buffer does not have a mapping. Map it in and copy */
+ unsigned int offset = phys & ~PAGE_MASK;
+ char *buffer;
+ unsigned int sz = 0;
+ unsigned long flags;
+
+ while (size) {
+ sz = min_t(size_t, PAGE_SIZE - offset, size);
+
+ local_irq_save(flags);
+ buffer = kmap_atomic(pfn_to_page(pfn),
+ KM_BOUNCE_READ);
+ if (dir == DMA_TO_DEVICE)
+ memcpy(dma_addr, buffer + offset, sz);
+ else
+ memcpy(buffer + offset, dma_addr, sz);
+ kunmap_atomic(buffer, KM_BOUNCE_READ);
+ local_irq_restore(flags);
+
+ size -= sz;
+ pfn++;
+ dma_addr += sz;
+ offset = 0;
+ }
+ } else {
+ if (dir == DMA_TO_DEVICE)
+ memcpy(dma_addr, phys_to_virt(phys), size);
+ else
+ memcpy(phys_to_virt(phys), dma_addr, size);
+ }
+}
+
+/*
+ * Allocates bounce buffer and returns its kernel virtual address.
+ */
+void *
+do_map_single(struct device *hwdev, phys_addr_t phys,
+ unsigned long start_dma_addr, size_t size, int dir)
+{
+ unsigned long flags;
+ char *dma_addr;
+ unsigned int nslots, stride, index, wrap;
+ int i;
+ unsigned long mask;
+ unsigned long offset_slots;
+ unsigned long max_slots;
+
+ mask = dma_get_seg_boundary(hwdev);
+ start_dma_addr = start_dma_addr & mask;
+ offset_slots = ALIGN(start_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
+
+ /*
+ * Carefully handle integer overflow which can occur when mask == ~0UL.
+ */
+ max_slots = mask + 1
+ ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT
+ : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT);
+
+ /*
+ * For mappings greater than a page, we limit the stride (and
+ * hence alignment) to a page size.
+ */
+ nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
+ if (size > PAGE_SIZE)
+ stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT));
+ else
+ stride = 1;
+
+ BUG_ON(!nslots);
+
+ /*
+ * Find suitable number of IO TLB entries size that will fit this
+ * request and allocate a buffer from that IO TLB pool.
+ */
+ spin_lock_irqsave(&io_tlb_lock, flags);
+ index = ALIGN(io_tlb_index, stride);
+ if (index >= io_tlb_nslabs)
+ index = 0;
+ wrap = index;
+
+ do {
+ while (iommu_is_span_boundary(index, nslots, offset_slots,
+ max_slots)) {
+ index += stride;
+ if (index >= io_tlb_nslabs)
+ index = 0;
+ if (index == wrap)
+ goto not_found;
+ }
+
+ /*
+ * If we find a slot that indicates we have 'nslots' number of
+ * contiguous buffers, we allocate the buffers from that slot
+ * and mark the entries as '0' indicating unavailable.
+ */
+ if (io_tlb_list[index] >= nslots) {
+ int count = 0;
+
+ for (i = index; i < (int) (index + nslots); i++)
+ io_tlb_list[i] = 0;
+ for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE)
+ != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--)
+ io_tlb_list[i] = ++count;
+ dma_addr = io_tlb_start + (index << IO_TLB_SHIFT);
+
+ /*
+ * Update the indices to avoid searching in the next
+ * round.
+ */
+ io_tlb_index = ((index + nslots) < io_tlb_nslabs
+ ? (index + nslots) : 0);
+
+ goto found;
+ }
+ index += stride;
+ if (index >= io_tlb_nslabs)
+ index = 0;
+ } while (index != wrap);
+
+not_found:
+ spin_unlock_irqrestore(&io_tlb_lock, flags);
+ return NULL;
+found:
+ spin_unlock_irqrestore(&io_tlb_lock, flags);
+
+ /*
+ * Save away the mapping from the original address to the DMA address.
+ * This is needed when we sync the memory. Then we sync the buffer if
+ * needed.
+ */
+ for (i = 0; i < nslots; i++)
+ io_tlb_orig_addr[index+i] = phys + (i << IO_TLB_SHIFT);
+ if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
+ swiotlb_bounce(phys, dma_addr, size, DMA_TO_DEVICE);
+
+ return dma_addr;
+}
+
+/*
+ * dma_addr is the kernel virtual address of the bounce buffer to unmap.
+ */
+void
+do_unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
+{
+ unsigned long flags;
+ int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
+ int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
+ phys_addr_t phys = io_tlb_orig_addr[index];
+
+ /*
+ * First, sync the memory before unmapping the entry
+ */
+ if (phys && ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)))
+ swiotlb_bounce(phys, dma_addr, size, DMA_FROM_DEVICE);
+
+ /*
+ * Return the buffer to the free list by setting the corresponding
+ * entries to indicate the number of contiguous entries available.
+ * While returning the entries to the free list, we merge the entries
+ * with slots below and above the pool being returned.
+ */
+ spin_lock_irqsave(&io_tlb_lock, flags);
+ {
+ count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ?
+ io_tlb_list[index + nslots] : 0);
+ /*
+ * Step 1: return the slots to the free list, merging the
+ * slots with superceeding slots
+ */
+ for (i = index + nslots - 1; i >= index; i--)
+ io_tlb_list[i] = ++count;
+ /*
+ * Step 2: merge the returned slots with the preceding slots,
+ * if available (non zero)
+ */
+ for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) !=
+ IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--)
+ io_tlb_list[i] = ++count;
+ }
+ spin_unlock_irqrestore(&io_tlb_lock, flags);
+}
+
+void
+do_sync_single(struct device *hwdev, char *dma_addr, size_t size,
+ int dir, int target)
+{
+ int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
+ phys_addr_t phys = io_tlb_orig_addr[index];
+
+ phys += ((unsigned long)dma_addr & ((1 << IO_TLB_SHIFT) - 1));
+
+ switch (target) {
+ case SYNC_FOR_CPU:
+ if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
+ swiotlb_bounce(phys, dma_addr, size, DMA_FROM_DEVICE);
+ else
+ BUG_ON(dir != DMA_TO_DEVICE);
+ break;
+ case SYNC_FOR_DEVICE:
+ if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
+ swiotlb_bounce(phys, dma_addr, size, DMA_TO_DEVICE);
+ else
+ BUG_ON(dir != DMA_FROM_DEVICE);
+ break;
+ default:
+ BUG();
+ }
+}
+
+void *
+swiotlb_alloc_coherent(struct device *hwdev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flags)
+{
+ dma_addr_t dev_addr;
+ void *ret;
+ int order = get_order(size);
+ u64 dma_mask = DMA_BIT_MASK(32);
+ unsigned long start_dma_addr;
+
+ if (hwdev && hwdev->coherent_dma_mask)
+ dma_mask = hwdev->coherent_dma_mask;
+
+ ret = (void *)__get_free_pages(flags, order);
+ if (ret && swiotlb_virt_to_bus(hwdev, ret) + size - 1 > dma_mask) {
+ /*
+ * The allocated memory isn't reachable by the device.
+ */
+ free_pages((unsigned long) ret, order);
+ ret = NULL;
+ }
+ if (!ret) {
+ /*
+ * We are either out of memory or the device can't DMA
+ * to GFP_DMA memory; fall back on do_map_single(), which
+ * will grab memory from the lowest available address range.
+ */
+ start_dma_addr = swiotlb_virt_to_bus(hwdev, io_tlb_start);
+ ret = do_map_single(hwdev, 0, start_dma_addr, size,
+ DMA_FROM_DEVICE);
+ if (!ret)
+ return NULL;
+ }
+
+ memset(ret, 0, size);
+ dev_addr = swiotlb_virt_to_bus(hwdev, ret);
+
+ /* Confirm address can be DMA'd by device */
+ if (dev_addr + size - 1 > dma_mask) {
+ dev_err(hwdev, "DMA: hwdev DMA mask = 0x%016Lx, " \
+ "dev_addr = 0x%016Lx\n",
+ (unsigned long long)dma_mask,
+ (unsigned long long)dev_addr);
+
+ /* DMA_TO_DEVICE to avoid memcpy in do_unmap_single */
+ do_unmap_single(hwdev, ret, size, DMA_TO_DEVICE);
+ return NULL;
+ }
+ *dma_handle = dev_addr;
+ return ret;
+}
+EXPORT_SYMBOL(swiotlb_alloc_coherent);
+
+void
+swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
+ dma_addr_t dev_addr)
+{
+ phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
+
+ WARN_ON(irqs_disabled());
+ if (!is_swiotlb_buffer(paddr))
+ free_pages((unsigned long)vaddr, get_order(size));
+ else
+ /* DMA_TO_DEVICE to avoid memcpy in do_unmap_single */
+ do_unmap_single(hwdev, vaddr, size, DMA_TO_DEVICE);
+}
+EXPORT_SYMBOL(swiotlb_free_coherent);
+
+static void
+swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
+{
+ /*
+ * Ran out of IOMMU space for this operation. This is very bad.
+ * Unfortunately the drivers cannot handle this operation properly.
+ * unless they check for dma_mapping_error (most don't)
+ * When the mapping is small enough return a static buffer to limit
+ * the damage, or panic when the transfer is too big.
+ */
+ dev_err(dev, "DMA: Out of SW-IOMMU space for %zu bytes.", size);
+
+ if (size <= io_tlb_overflow || !do_panic)
+ return;
+
+ if (dir == DMA_BIDIRECTIONAL)
+ panic("DMA: Random memory could be DMA accessed\n");
+ if (dir == DMA_FROM_DEVICE)
+ panic("DMA: Random memory could be DMA written\n");
+ if (dir == DMA_TO_DEVICE)
+ panic("DMA: Random memory could be DMA read\n");
+}
+
+/*
+ * Map a single buffer of the indicated size for DMA in streaming mode. The
+ * physical address to use is returned.
+ *
+ * Once the device is given the dma address, the device owns this memory until
+ * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed.
+ */
+dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ unsigned long start_dma_addr;
+ phys_addr_t phys = page_to_phys(page) + offset;
+ dma_addr_t dev_addr = phys_to_dma(dev, phys);
+ void *map;
+
+ BUG_ON(dir == DMA_NONE);
+ /*
+ * If the address happens to be in the device's DMA window,
+ * we can safely return the device addr and not worry about bounce
+ * buffering it.
+ */
+ if (dma_capable(dev, dev_addr, size) && !swiotlb_force)
+ return dev_addr;
+
+ /*
+ * Oh well, have to allocate and map a bounce buffer.
+ */
+ start_dma_addr = swiotlb_virt_to_bus(dev, io_tlb_start);
+ map = do_map_single(dev, phys, start_dma_addr, size, dir);
+ if (!map) {
+ swiotlb_full(dev, size, dir, 1);
+ map = io_tlb_overflow_buffer;
+ }
+
+ dev_addr = swiotlb_virt_to_bus(dev, map);
+
+ /*
+ * Ensure that the address returned is DMA'ble
+ */
+ if (!dma_capable(dev, dev_addr, size))
+ panic("DMA: swiotlb_map_single: bounce buffer is not DMA'ble");
+
+ return dev_addr;
+}
+EXPORT_SYMBOL_GPL(swiotlb_map_page);
+
+/*
+ * Unmap a single streaming mode DMA translation. The dma_addr and size must
+ * match what was provided for in a previous swiotlb_map_page call. All
+ * other usages are undefined.
+ *
+ * After this call, reads by the cpu to the buffer are guaranteed to see
+ * whatever the device wrote there.
+ */
+static void unmap_single(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, int dir)
+{
+ phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
+
+ BUG_ON(dir == DMA_NONE);
+
+ if (is_swiotlb_buffer(paddr)) {
+ do_unmap_single(hwdev, phys_to_virt(paddr), size, dir);
+ return;
+ }
+
+ if (dir != DMA_FROM_DEVICE)
+ return;
+
+ /*
+ * phys_to_virt doesn't work with hihgmem page but we could
+ * call dma_mark_clean() with hihgmem page here. However, we
+ * are fine since dma_mark_clean() is null on POWERPC. We can
+ * make dma_mark_clean() take a physical address if necessary.
+ */
+ dma_mark_clean(phys_to_virt(paddr), size);
+}
+
+void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ unmap_single(hwdev, dev_addr, size, dir);
+}
+EXPORT_SYMBOL_GPL(swiotlb_unmap_page);
+
+/*
+ * Make physical memory consistent for a single streaming mode DMA translation
+ * after a transfer.
+ *
+ * If you perform a swiotlb_map_page() but wish to interrogate the buffer
+ * using the cpu, yet do not wish to teardown the dma mapping, you must
+ * call this function before doing so. At the next point you give the dma
+ * address back to the card, you must first perform a
+ * swiotlb_dma_sync_for_device, and then the device again owns the buffer
+ */
+static void
+swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, int dir, int target)
+{
+ phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
+
+ BUG_ON(dir == DMA_NONE);
+
+ if (is_swiotlb_buffer(paddr)) {
+ do_sync_single(hwdev, phys_to_virt(paddr), size, dir, target);
+ return;
+ }
+
+ if (dir != DMA_FROM_DEVICE)
+ return;
+
+ dma_mark_clean(phys_to_virt(paddr), size);
+}
+
+void
+swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, enum dma_data_direction dir)
+{
+ swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
+}
+EXPORT_SYMBOL(swiotlb_sync_single_for_cpu);
+
+void
+swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, enum dma_data_direction dir)
+{
+ swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
+}
+EXPORT_SYMBOL(swiotlb_sync_single_for_device);
+
+/*
+ * Same as above, but for a sub-range of the mapping.
+ */
+static void
+swiotlb_sync_single_range(struct device *hwdev, dma_addr_t dev_addr,
+ unsigned long offset, size_t size,
+ int dir, int target)
+{
+ swiotlb_sync_single(hwdev, dev_addr + offset, size, dir, target);
+}
+
+void
+swiotlb_sync_single_range_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir)
+{
+ swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
+ SYNC_FOR_CPU);
+}
+EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_cpu);
+
+void
+swiotlb_sync_single_range_for_device(struct device *hwdev, dma_addr_t dev_addr,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir)
+{
+ swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
+ SYNC_FOR_DEVICE);
+}
+EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device);
+
+/*
+ * Map a set of buffers described by scatterlist in streaming mode for DMA.
+ * This is the scatter-gather version of the above swiotlb_map_page
+ * interface. Here the scatter gather list elements are each tagged with the
+ * appropriate dma address and length. They are obtained via
+ * sg_dma_{address,length}(SG).
+ *
+ * NOTE: An implementation may be able to use a smaller number of
+ * DMA address/length pairs than there are SG table elements.
+ * (for example via virtual mapping capabilities)
+ * The routine returns the number of addr/length pairs actually
+ * used, at most nents.
+ *
+ * Device ownership issues as mentioned above for swiotlb_map_page are the
+ * same here.
+ */
+int
+swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
+ enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ unsigned long start_dma_addr;
+ struct scatterlist *sg;
+ int i;
+
+ BUG_ON(dir == DMA_NONE);
+
+ start_dma_addr = swiotlb_virt_to_bus(hwdev, io_tlb_start);
+ for_each_sg(sgl, sg, nelems, i) {
+ phys_addr_t paddr = sg_phys(sg);
+ dma_addr_t dev_addr = phys_to_dma(hwdev, paddr);
+
+ if (swiotlb_force ||
+ !dma_capable(hwdev, dev_addr, sg->length)) {
+ void *map = do_map_single(hwdev, sg_phys(sg),
+ start_dma_addr,
+ sg->length, dir);
+ if (!map) {
+ /* Don't panic here, we expect map_sg users
+ to do proper error handling. */
+ swiotlb_full(hwdev, sg->length, dir, 0);
+ swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
+ attrs);
+ sgl[0].dma_length = 0;
+ return 0;
+ }
+ sg->dma_address = swiotlb_virt_to_bus(hwdev, map);
+ } else
+ sg->dma_address = dev_addr;
+ sg->dma_length = sg->length;
+ }
+ return nelems;
+}
+EXPORT_SYMBOL(swiotlb_map_sg_attrs);
+
+int
+swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
+ int dir)
+{
+ return swiotlb_map_sg_attrs(hwdev, sgl, nelems, dir, NULL);
+}
+EXPORT_SYMBOL(swiotlb_map_sg);
+
+/*
+ * Unmap a set of streaming mode DMA translations. Again, cpu read rules
+ * concerning calls here are the same as for swiotlb_unmap_page() above.
+ */
+void
+swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
+ int nelems, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ struct scatterlist *sg;
+ int i;
+
+ BUG_ON(dir == DMA_NONE);
+
+ for_each_sg(sgl, sg, nelems, i)
+ unmap_single(hwdev, sg->dma_address, sg->dma_length, dir);
+
+}
+EXPORT_SYMBOL(swiotlb_unmap_sg_attrs);
+
+void
+swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
+ int dir)
+{
+ return swiotlb_unmap_sg_attrs(hwdev, sgl, nelems, dir, NULL);
+}
+EXPORT_SYMBOL(swiotlb_unmap_sg);
+
+/*
+ * Make physical memory consistent for a set of streaming mode DMA translations
+ * after a transfer.
+ *
+ * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
+ * and usage.
+ */
+static void
+swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
+ int nelems, int dir, int target)
+{
+ struct scatterlist *sg;
+ int i;
+
+ for_each_sg(sgl, sg, nelems, i)
+ swiotlb_sync_single(hwdev, sg->dma_address,
+ sg->dma_length, dir, target);
+}
+
+void
+swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
+ int nelems, enum dma_data_direction dir)
+{
+ swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
+}
+EXPORT_SYMBOL(swiotlb_sync_sg_for_cpu);
+
+void
+swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
+ int nelems, enum dma_data_direction dir)
+{
+ swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
+}
+EXPORT_SYMBOL(swiotlb_sync_sg_for_device);
+
+int
+swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
+{
+ return (dma_addr == swiotlb_virt_to_bus(hwdev, io_tlb_overflow_buffer));
+}
+EXPORT_SYMBOL(swiotlb_dma_mapping_error);
+
+/*
+ * Return whether the given device DMA address mask can be supported
+ * properly. For example, if your device can only drive the low 24-bits
+ * during bus mastering, then you would pass 0x00ffffff as the mask to
+ * this function.
+ */
+int
+swiotlb_dma_supported(struct device *hwdev, u64 mask)
+{
+ return swiotlb_virt_to_bus(hwdev, io_tlb_end - 1) <= mask;
+}
+EXPORT_SYMBOL(swiotlb_dma_supported);
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
deleted file mode 100644
index c982d33..0000000
--- a/lib/swiotlb.c
+++ /dev/null
@@ -1,957 +0,0 @@
-/*
- * Dynamic DMA mapping support.
- *
- * This implementation is a fallback for platforms that do not support
- * I/O TLBs (aka DMA address translation hardware).
- * Copyright (C) 2000 Asit Mallick <Asit.K.Mallick@xxxxxxxxx>
- * Copyright (C) 2000 Goutham Rao <goutham.rao@xxxxxxxxx>
- * Copyright (C) 2000, 2003 Hewlett-Packard Co
- * David Mosberger-Tang <davidm@xxxxxxxxxx>
- *
- * 03/05/07 davidm Switch from PCI-DMA to generic device DMA API.
- * 00/12/13 davidm Rename to swiotlb.c and add mark_clean() to avoid
- * unnecessary i-cache flushing.
- * 04/07/.. ak Better overflow handling. Assorted fixes.
- * 05/09/10 linville Add support for syncing ranges, support syncing for
- * DMA_BIDIRECTIONAL mappings, miscellaneous cleanup.
- * 08/12/11 beckyb Add highmem support
- */
-
-#include <linux/cache.h>
-#include <linux/dma-mapping.h>
-#include <linux/mm.h>
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <linux/string.h>
-#include <linux/swiotlb.h>
-#include <linux/pfn.h>
-#include <linux/types.h>
-#include <linux/ctype.h>
-#include <linux/highmem.h>
-
-#include <linux/io.h>
-#include <asm/dma.h>
-#include <linux/scatterlist.h>
-
-#include <linux/init.h>
-#include <linux/bootmem.h>
-#include <linux/iommu-helper.h>
-
-#define OFFSET(val, align) ((unsigned long) ((val) & ((align) - 1)))
-
-#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))
-
-/*
- * Minimum IO TLB size to bother booting with. Systems with mainly
- * 64bit capable cards will only lightly use the swiotlb. If we can't
- * allocate a contiguous 1MB, we're probably in trouble anyway.
- */
-#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
-
-int swiotlb_force;
-
-/*
- * Used to do a quick range check in do_unmap_single and
- * do_sync_single_*, to see if the memory was in fact allocated by this
- * API.
- */
-char *io_tlb_start, *io_tlb_end;
-
-/*
- * The number of IO TLB blocks (in groups of 64) betweeen io_tlb_start and
- * io_tlb_end. This is command line adjustable via setup_io_tlb_npages.
- */
-unsigned long io_tlb_nslabs;
-
-/*
- * When the IOMMU overflows we return a fallback buffer. This sets the size.
- */
-unsigned long io_tlb_overflow = 32*1024;
-
-void *io_tlb_overflow_buffer;
-
-/*
- * This is a free list describing the number of free entries available from
- * each index
- */
-static unsigned int *io_tlb_list;
-static unsigned int io_tlb_index;
-
-/*
- * We need to save away the original address corresponding to a mapped entry
- * for the sync operations.
- */
-static phys_addr_t *io_tlb_orig_addr;
-
-/*
- * Protect the above data structures in the map and unmap calls
- */
-static DEFINE_SPINLOCK(io_tlb_lock);
-
-static int late_alloc;
-
-static int __init
-setup_io_tlb_npages(char *str)
-{
- int get_value(const char *token, char *str, char **endp)
- {
- ssize_t len;
- int val = 0;
-
- len = strlen(token);
- if (!strncmp(str, token, len)) {
- str += len;
- if (*str == '=')
- ++str;
- if (*str != '\0')
- val = simple_strtoul(str, endp, 0);
- }
- *endp = str;
- return val;
- }
-
- int val;
-
- while (*str) {
- /* The old syntax */
- if (isdigit(*str)) {
- io_tlb_nslabs = simple_strtoul(str, &str, 0);
- /* avoid tail segment of size < IO_TLB_SEGSIZE */
- io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
- }
- if (!strncmp(str, "force", 5))
- swiotlb_force = 1;
- /* The new syntax: swiotlb=nslabs=16384,overflow=32768,force */
- val = get_value("nslabs", str, &str);
- if (val)
- io_tlb_nslabs = ALIGN(val, IO_TLB_SEGSIZE);
-
- val = get_value("overflow", str, &str);
- if (val)
- io_tlb_overflow = val;
- str = strpbrk(str, ",");
- if (!str)
- break;
- str++; /* skip ',' */
- }
- return 1;
-}
-__setup("swiotlb=", setup_io_tlb_npages);
-
-/* Note that this doesn't work with highmem page */
-static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
- volatile void *address)
-{
- return phys_to_dma(hwdev, virt_to_phys(address));
-}
-
-void swiotlb_print_info(void)
-{
- unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT;
- phys_addr_t pstart, pend;
-
- pstart = virt_to_phys(io_tlb_start);
- pend = virt_to_phys(io_tlb_end);
-
- printk(KERN_INFO "DMA: Placing %luMB software IO TLB between %p - %p\n",
- bytes >> 20, io_tlb_start, io_tlb_end);
- printk(KERN_INFO "DMA: software IO TLB at phys %#llx - %#llx\n",
- (unsigned long long)pstart,
- (unsigned long long)pend);
-}
-
-/*
- * Statically reserve bounce buffer space and initialize bounce buffer data
- * structures for the software IO TLB used to implement the DMA API.
- */
-void __init
-swiotlb_init_early(size_t default_size, int verbose)
-{
- unsigned long i, bytes;
-
- if (!io_tlb_nslabs) {
- io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
- io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
- }
-
- bytes = io_tlb_nslabs << IO_TLB_SHIFT;
-
- /*
- * Get IO TLB memory from the low pages
- */
- io_tlb_start = alloc_bootmem_low_pages(bytes);
- if (!io_tlb_start)
- panic("DMA: Cannot allocate SWIOTLB buffer");
- io_tlb_end = io_tlb_start + bytes;
-
- /*
- * Allocate and initialize the free list array. This array is used
- * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
- * between io_tlb_start and io_tlb_end.
- */
- io_tlb_list = alloc_bootmem(io_tlb_nslabs * sizeof(int));
- for (i = 0; i < io_tlb_nslabs; i++)
- io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
- io_tlb_index = 0;
- io_tlb_orig_addr = alloc_bootmem(io_tlb_nslabs * sizeof(phys_addr_t));
-
- /*
- * Get the overflow emergency buffer
- */
- io_tlb_overflow_buffer = alloc_bootmem_low(io_tlb_overflow);
- if (!io_tlb_overflow_buffer)
- panic("DMA: Cannot allocate SWIOTLB overflow buffer!\n");
- if (verbose)
- swiotlb_print_info();
-}
-
-void __init
-swiotlb_init(int verbose)
-{
- swiotlb_init_early(64 * (1<<20), verbose); /* default to 64MB */
-}
-
-/*
- * Systems with larger DMA zones (those that don't support ISA) can
- * initialize the swiotlb later using the slab allocator if needed.
- * This should be just like above, but with some error catching.
- */
-int
-swiotlb_init_late(size_t default_size)
-{
- unsigned long i, bytes, req_nslabs = io_tlb_nslabs;
- unsigned int order;
-
- if (!io_tlb_nslabs) {
- io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
- io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
- }
-
- /*
- * Get IO TLB memory from the low pages
- */
- order = get_order(io_tlb_nslabs << IO_TLB_SHIFT);
- io_tlb_nslabs = SLABS_PER_PAGE << order;
- bytes = io_tlb_nslabs << IO_TLB_SHIFT;
-
- while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
- io_tlb_start = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
- order);
- if (io_tlb_start)
- break;
- order--;
- }
-
- if (!io_tlb_start)
- goto cleanup1;
-
- if (order != get_order(bytes)) {
- printk(KERN_WARNING "DMA: Warning: only able to allocate %ld MB"
- " for software IO TLB\n", (PAGE_SIZE << order) >> 20);
- io_tlb_nslabs = SLABS_PER_PAGE << order;
- bytes = io_tlb_nslabs << IO_TLB_SHIFT;
- }
- io_tlb_end = io_tlb_start + bytes;
- memset(io_tlb_start, 0, bytes);
-
- /*
- * Allocate and initialize the free list array. This array is used
- * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
- * between io_tlb_start and io_tlb_end.
- */
- io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL,
- get_order(io_tlb_nslabs * sizeof(int)));
- if (!io_tlb_list)
- goto cleanup2;
-
- for (i = 0; i < io_tlb_nslabs; i++)
- io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
- io_tlb_index = 0;
-
- io_tlb_orig_addr = (phys_addr_t *) __get_free_pages(GFP_KERNEL,
- get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
- if (!io_tlb_orig_addr)
- goto cleanup3;
-
- memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(phys_addr_t));
-
- /*
- * Get the overflow emergency buffer
- */
- io_tlb_overflow_buffer = (void *)__get_free_pages(GFP_DMA,
- get_order(io_tlb_overflow));
- if (!io_tlb_overflow_buffer)
- goto cleanup4;
-
- swiotlb_print_info();
-
- late_alloc = 1;
-
- return 0;
-
-cleanup4:
- free_pages((unsigned long)io_tlb_orig_addr,
- get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
- io_tlb_orig_addr = NULL;
-cleanup3:
- free_pages((unsigned long)io_tlb_list,
- get_order(io_tlb_nslabs * sizeof(int)));
- io_tlb_list = NULL;
-cleanup2:
- io_tlb_end = NULL;
- free_pages((unsigned long)io_tlb_start, order);
- io_tlb_start = NULL;
-cleanup1:
- io_tlb_nslabs = req_nslabs;
- return -ENOMEM;
-}
-
-void __init swiotlb_free(void)
-{
- if (!io_tlb_overflow_buffer)
- return;
-
- if (late_alloc) {
- free_pages((unsigned long)io_tlb_overflow_buffer,
- get_order(io_tlb_overflow));
- free_pages((unsigned long)io_tlb_orig_addr,
- get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
- free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
- sizeof(int)));
- free_pages((unsigned long)io_tlb_start,
- get_order(io_tlb_nslabs << IO_TLB_SHIFT));
- } else {
- free_bootmem_late(__pa(io_tlb_overflow_buffer),
- io_tlb_overflow);
- free_bootmem_late(__pa(io_tlb_orig_addr),
- io_tlb_nslabs * sizeof(phys_addr_t));
- free_bootmem_late(__pa(io_tlb_list),
- io_tlb_nslabs * sizeof(int));
- free_bootmem_late(__pa(io_tlb_start),
- io_tlb_nslabs << IO_TLB_SHIFT);
- }
-}
-
-int is_swiotlb_buffer(phys_addr_t paddr)
-{
- return paddr >= virt_to_phys(io_tlb_start) &&
- paddr < virt_to_phys(io_tlb_end);
-}
-
-/*
- * Bounce: copy the swiotlb buffer back to the original dma location
- */
-void swiotlb_bounce(phys_addr_t phys, char *dma_addr, size_t size,
- enum dma_data_direction dir)
-{
- unsigned long pfn = PFN_DOWN(phys);
-
- if (PageHighMem(pfn_to_page(pfn))) {
- /* The buffer does not have a mapping. Map it in and copy */
- unsigned int offset = phys & ~PAGE_MASK;
- char *buffer;
- unsigned int sz = 0;
- unsigned long flags;
-
- while (size) {
- sz = min_t(size_t, PAGE_SIZE - offset, size);
-
- local_irq_save(flags);
- buffer = kmap_atomic(pfn_to_page(pfn),
- KM_BOUNCE_READ);
- if (dir == DMA_TO_DEVICE)
- memcpy(dma_addr, buffer + offset, sz);
- else
- memcpy(buffer + offset, dma_addr, sz);
- kunmap_atomic(buffer, KM_BOUNCE_READ);
- local_irq_restore(flags);
-
- size -= sz;
- pfn++;
- dma_addr += sz;
- offset = 0;
- }
- } else {
- if (dir == DMA_TO_DEVICE)
- memcpy(dma_addr, phys_to_virt(phys), size);
- else
- memcpy(phys_to_virt(phys), dma_addr, size);
- }
-}
-
-/*
- * Allocates bounce buffer and returns its kernel virtual address.
- */
-void *
-do_map_single(struct device *hwdev, phys_addr_t phys,
- unsigned long start_dma_addr, size_t size, int dir)
-{
- unsigned long flags;
- char *dma_addr;
- unsigned int nslots, stride, index, wrap;
- int i;
- unsigned long mask;
- unsigned long offset_slots;
- unsigned long max_slots;
-
- mask = dma_get_seg_boundary(hwdev);
- start_dma_addr = start_dma_addr & mask;
- offset_slots = ALIGN(start_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
-
- /*
- * Carefully handle integer overflow which can occur when mask == ~0UL.
- */
- max_slots = mask + 1
- ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT
- : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT);
-
- /*
- * For mappings greater than a page, we limit the stride (and
- * hence alignment) to a page size.
- */
- nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
- if (size > PAGE_SIZE)
- stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT));
- else
- stride = 1;
-
- BUG_ON(!nslots);
-
- /*
- * Find suitable number of IO TLB entries size that will fit this
- * request and allocate a buffer from that IO TLB pool.
- */
- spin_lock_irqsave(&io_tlb_lock, flags);
- index = ALIGN(io_tlb_index, stride);
- if (index >= io_tlb_nslabs)
- index = 0;
- wrap = index;
-
- do {
- while (iommu_is_span_boundary(index, nslots, offset_slots,
- max_slots)) {
- index += stride;
- if (index >= io_tlb_nslabs)
- index = 0;
- if (index == wrap)
- goto not_found;
- }
-
- /*
- * If we find a slot that indicates we have 'nslots' number of
- * contiguous buffers, we allocate the buffers from that slot
- * and mark the entries as '0' indicating unavailable.
- */
- if (io_tlb_list[index] >= nslots) {
- int count = 0;
-
- for (i = index; i < (int) (index + nslots); i++)
- io_tlb_list[i] = 0;
- for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE)
- != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--)
- io_tlb_list[i] = ++count;
- dma_addr = io_tlb_start + (index << IO_TLB_SHIFT);
-
- /*
- * Update the indices to avoid searching in the next
- * round.
- */
- io_tlb_index = ((index + nslots) < io_tlb_nslabs
- ? (index + nslots) : 0);
-
- goto found;
- }
- index += stride;
- if (index >= io_tlb_nslabs)
- index = 0;
- } while (index != wrap);
-
-not_found:
- spin_unlock_irqrestore(&io_tlb_lock, flags);
- return NULL;
-found:
- spin_unlock_irqrestore(&io_tlb_lock, flags);
-
- /*
- * Save away the mapping from the original address to the DMA address.
- * This is needed when we sync the memory. Then we sync the buffer if
- * needed.
- */
- for (i = 0; i < nslots; i++)
- io_tlb_orig_addr[index+i] = phys + (i << IO_TLB_SHIFT);
- if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
- swiotlb_bounce(phys, dma_addr, size, DMA_TO_DEVICE);
-
- return dma_addr;
-}
-
-/*
- * dma_addr is the kernel virtual address of the bounce buffer to unmap.
- */
-void
-do_unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
-{
- unsigned long flags;
- int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
- int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
- phys_addr_t phys = io_tlb_orig_addr[index];
-
- /*
- * First, sync the memory before unmapping the entry
- */
- if (phys && ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)))
- swiotlb_bounce(phys, dma_addr, size, DMA_FROM_DEVICE);
-
- /*
- * Return the buffer to the free list by setting the corresponding
- * entries to indicate the number of contiguous entries available.
- * While returning the entries to the free list, we merge the entries
- * with slots below and above the pool being returned.
- */
- spin_lock_irqsave(&io_tlb_lock, flags);
- {
- count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ?
- io_tlb_list[index + nslots] : 0);
- /*
- * Step 1: return the slots to the free list, merging the
- * slots with superceeding slots
- */
- for (i = index + nslots - 1; i >= index; i--)
- io_tlb_list[i] = ++count;
- /*
- * Step 2: merge the returned slots with the preceding slots,
- * if available (non zero)
- */
- for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) !=
- IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--)
- io_tlb_list[i] = ++count;
- }
- spin_unlock_irqrestore(&io_tlb_lock, flags);
-}
-
-void
-do_sync_single(struct device *hwdev, char *dma_addr, size_t size,
- int dir, int target)
-{
- int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
- phys_addr_t phys = io_tlb_orig_addr[index];
-
- phys += ((unsigned long)dma_addr & ((1 << IO_TLB_SHIFT) - 1));
-
- switch (target) {
- case SYNC_FOR_CPU:
- if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
- swiotlb_bounce(phys, dma_addr, size, DMA_FROM_DEVICE);
- else
- BUG_ON(dir != DMA_TO_DEVICE);
- break;
- case SYNC_FOR_DEVICE:
- if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
- swiotlb_bounce(phys, dma_addr, size, DMA_TO_DEVICE);
- else
- BUG_ON(dir != DMA_FROM_DEVICE);
- break;
- default:
- BUG();
- }
-}
-
-void *
-swiotlb_alloc_coherent(struct device *hwdev, size_t size,
- dma_addr_t *dma_handle, gfp_t flags)
-{
- dma_addr_t dev_addr;
- void *ret;
- int order = get_order(size);
- u64 dma_mask = DMA_BIT_MASK(32);
- unsigned long start_dma_addr;
-
- if (hwdev && hwdev->coherent_dma_mask)
- dma_mask = hwdev->coherent_dma_mask;
-
- ret = (void *)__get_free_pages(flags, order);
- if (ret && swiotlb_virt_to_bus(hwdev, ret) + size - 1 > dma_mask) {
- /*
- * The allocated memory isn't reachable by the device.
- */
- free_pages((unsigned long) ret, order);
- ret = NULL;
- }
- if (!ret) {
- /*
- * We are either out of memory or the device can't DMA
- * to GFP_DMA memory; fall back on do_map_single(), which
- * will grab memory from the lowest available address range.
- */
- start_dma_addr = swiotlb_virt_to_bus(hwdev, io_tlb_start);
- ret = do_map_single(hwdev, 0, start_dma_addr, size,
- DMA_FROM_DEVICE);
- if (!ret)
- return NULL;
- }
-
- memset(ret, 0, size);
- dev_addr = swiotlb_virt_to_bus(hwdev, ret);
-
- /* Confirm address can be DMA'd by device */
- if (dev_addr + size - 1 > dma_mask) {
- dev_err(hwdev, "DMA: hwdev DMA mask = 0x%016Lx, " \
- "dev_addr = 0x%016Lx\n",
- (unsigned long long)dma_mask,
- (unsigned long long)dev_addr);
-
- /* DMA_TO_DEVICE to avoid memcpy in do_unmap_single */
- do_unmap_single(hwdev, ret, size, DMA_TO_DEVICE);
- return NULL;
- }
- *dma_handle = dev_addr;
- return ret;
-}
-EXPORT_SYMBOL(swiotlb_alloc_coherent);
-
-void
-swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
- dma_addr_t dev_addr)
-{
- phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
-
- WARN_ON(irqs_disabled());
- if (!is_swiotlb_buffer(paddr))
- free_pages((unsigned long)vaddr, get_order(size));
- else
- /* DMA_TO_DEVICE to avoid memcpy in do_unmap_single */
- do_unmap_single(hwdev, vaddr, size, DMA_TO_DEVICE);
-}
-EXPORT_SYMBOL(swiotlb_free_coherent);
-
-static void
-swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
-{
- /*
- * Ran out of IOMMU space for this operation. This is very bad.
- * Unfortunately the drivers cannot handle this operation properly.
- * unless they check for dma_mapping_error (most don't)
- * When the mapping is small enough return a static buffer to limit
- * the damage, or panic when the transfer is too big.
- */
- dev_err(dev, "DMA: Out of SW-IOMMU space for %zu bytes.", size);
-
- if (size <= io_tlb_overflow || !do_panic)
- return;
-
- if (dir == DMA_BIDIRECTIONAL)
- panic("DMA: Random memory could be DMA accessed\n");
- if (dir == DMA_FROM_DEVICE)
- panic("DMA: Random memory could be DMA written\n");
- if (dir == DMA_TO_DEVICE)
- panic("DMA: Random memory could be DMA read\n");
-}
-
-/*
- * Map a single buffer of the indicated size for DMA in streaming mode. The
- * physical address to use is returned.
- *
- * Once the device is given the dma address, the device owns this memory until
- * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed.
- */
-dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction dir,
- struct dma_attrs *attrs)
-{
- unsigned long start_dma_addr;
- phys_addr_t phys = page_to_phys(page) + offset;
- dma_addr_t dev_addr = phys_to_dma(dev, phys);
- void *map;
-
- BUG_ON(dir == DMA_NONE);
- /*
- * If the address happens to be in the device's DMA window,
- * we can safely return the device addr and not worry about bounce
- * buffering it.
- */
- if (dma_capable(dev, dev_addr, size) && !swiotlb_force)
- return dev_addr;
-
- /*
- * Oh well, have to allocate and map a bounce buffer.
- */
- start_dma_addr = swiotlb_virt_to_bus(dev, io_tlb_start);
- map = do_map_single(dev, phys, start_dma_addr, size, dir);
- if (!map) {
- swiotlb_full(dev, size, dir, 1);
- map = io_tlb_overflow_buffer;
- }
-
- dev_addr = swiotlb_virt_to_bus(dev, map);
-
- /*
- * Ensure that the address returned is DMA'ble
- */
- if (!dma_capable(dev, dev_addr, size))
- panic("DMA: swiotlb_map_single: bounce buffer is not DMA'ble");
-
- return dev_addr;
-}
-EXPORT_SYMBOL_GPL(swiotlb_map_page);
-
-/*
- * Unmap a single streaming mode DMA translation. The dma_addr and size must
- * match what was provided for in a previous swiotlb_map_page call. All
- * other usages are undefined.
- *
- * After this call, reads by the cpu to the buffer are guaranteed to see
- * whatever the device wrote there.
- */
-static void unmap_single(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, int dir)
-{
- phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
-
- BUG_ON(dir == DMA_NONE);
-
- if (is_swiotlb_buffer(paddr)) {
- do_unmap_single(hwdev, phys_to_virt(paddr), size, dir);
- return;
- }
-
- if (dir != DMA_FROM_DEVICE)
- return;
-
- /*
- * phys_to_virt doesn't work with hihgmem page but we could
- * call dma_mark_clean() with hihgmem page here. However, we
- * are fine since dma_mark_clean() is null on POWERPC. We can
- * make dma_mark_clean() take a physical address if necessary.
- */
- dma_mark_clean(phys_to_virt(paddr), size);
-}
-
-void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, enum dma_data_direction dir,
- struct dma_attrs *attrs)
-{
- unmap_single(hwdev, dev_addr, size, dir);
-}
-EXPORT_SYMBOL_GPL(swiotlb_unmap_page);
-
-/*
- * Make physical memory consistent for a single streaming mode DMA translation
- * after a transfer.
- *
- * If you perform a swiotlb_map_page() but wish to interrogate the buffer
- * using the cpu, yet do not wish to teardown the dma mapping, you must
- * call this function before doing so. At the next point you give the dma
- * address back to the card, you must first perform a
- * swiotlb_dma_sync_for_device, and then the device again owns the buffer
- */
-static void
-swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, int dir, int target)
-{
- phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
-
- BUG_ON(dir == DMA_NONE);
-
- if (is_swiotlb_buffer(paddr)) {
- do_sync_single(hwdev, phys_to_virt(paddr), size, dir, target);
- return;
- }
-
- if (dir != DMA_FROM_DEVICE)
- return;
-
- dma_mark_clean(phys_to_virt(paddr), size);
-}
-
-void
-swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, enum dma_data_direction dir)
-{
- swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
-}
-EXPORT_SYMBOL(swiotlb_sync_single_for_cpu);
-
-void
-swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, enum dma_data_direction dir)
-{
- swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
-}
-EXPORT_SYMBOL(swiotlb_sync_single_for_device);
-
-/*
- * Same as above, but for a sub-range of the mapping.
- */
-static void
-swiotlb_sync_single_range(struct device *hwdev, dma_addr_t dev_addr,
- unsigned long offset, size_t size,
- int dir, int target)
-{
- swiotlb_sync_single(hwdev, dev_addr + offset, size, dir, target);
-}
-
-void
-swiotlb_sync_single_range_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
- unsigned long offset, size_t size,
- enum dma_data_direction dir)
-{
- swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
- SYNC_FOR_CPU);
-}
-EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_cpu);
-
-void
-swiotlb_sync_single_range_for_device(struct device *hwdev, dma_addr_t dev_addr,
- unsigned long offset, size_t size,
- enum dma_data_direction dir)
-{
- swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
- SYNC_FOR_DEVICE);
-}
-EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device);
-
-/*
- * Map a set of buffers described by scatterlist in streaming mode for DMA.
- * This is the scatter-gather version of the above swiotlb_map_page
- * interface. Here the scatter gather list elements are each tagged with the
- * appropriate dma address and length. They are obtained via
- * sg_dma_{address,length}(SG).
- *
- * NOTE: An implementation may be able to use a smaller number of
- * DMA address/length pairs than there are SG table elements.
- * (for example via virtual mapping capabilities)
- * The routine returns the number of addr/length pairs actually
- * used, at most nents.
- *
- * Device ownership issues as mentioned above for swiotlb_map_page are the
- * same here.
- */
-int
-swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
- enum dma_data_direction dir, struct dma_attrs *attrs)
-{
- unsigned long start_dma_addr;
- struct scatterlist *sg;
- int i;
-
- BUG_ON(dir == DMA_NONE);
-
- start_dma_addr = swiotlb_virt_to_bus(hwdev, io_tlb_start);
- for_each_sg(sgl, sg, nelems, i) {
- phys_addr_t paddr = sg_phys(sg);
- dma_addr_t dev_addr = phys_to_dma(hwdev, paddr);
-
- if (swiotlb_force ||
- !dma_capable(hwdev, dev_addr, sg->length)) {
- void *map = do_map_single(hwdev, sg_phys(sg),
- start_dma_addr,
- sg->length, dir);
- if (!map) {
- /* Don't panic here, we expect map_sg users
- to do proper error handling. */
- swiotlb_full(hwdev, sg->length, dir, 0);
- swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
- attrs);
- sgl[0].dma_length = 0;
- return 0;
- }
- sg->dma_address = swiotlb_virt_to_bus(hwdev, map);
- } else
- sg->dma_address = dev_addr;
- sg->dma_length = sg->length;
- }
- return nelems;
-}
-EXPORT_SYMBOL(swiotlb_map_sg_attrs);
-
-int
-swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
- int dir)
-{
- return swiotlb_map_sg_attrs(hwdev, sgl, nelems, dir, NULL);
-}
-EXPORT_SYMBOL(swiotlb_map_sg);
-
-/*
- * Unmap a set of streaming mode DMA translations. Again, cpu read rules
- * concerning calls here are the same as for swiotlb_unmap_page() above.
- */
-void
-swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
- int nelems, enum dma_data_direction dir,
- struct dma_attrs *attrs)
-{
- struct scatterlist *sg;
- int i;
-
- BUG_ON(dir == DMA_NONE);
-
- for_each_sg(sgl, sg, nelems, i)
- unmap_single(hwdev, sg->dma_address, sg->dma_length, dir);
-
-}
-EXPORT_SYMBOL(swiotlb_unmap_sg_attrs);
-
-void
-swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
- int dir)
-{
- return swiotlb_unmap_sg_attrs(hwdev, sgl, nelems, dir, NULL);
-}
-EXPORT_SYMBOL(swiotlb_unmap_sg);
-
-/*
- * Make physical memory consistent for a set of streaming mode DMA translations
- * after a transfer.
- *
- * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
- * and usage.
- */
-static void
-swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
- int nelems, int dir, int target)
-{
- struct scatterlist *sg;
- int i;
-
- for_each_sg(sgl, sg, nelems, i)
- swiotlb_sync_single(hwdev, sg->dma_address,
- sg->dma_length, dir, target);
-}
-
-void
-swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
- int nelems, enum dma_data_direction dir)
-{
- swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
-}
-EXPORT_SYMBOL(swiotlb_sync_sg_for_cpu);
-
-void
-swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
- int nelems, enum dma_data_direction dir)
-{
- swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
-}
-EXPORT_SYMBOL(swiotlb_sync_sg_for_device);
-
-int
-swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
-{
- return (dma_addr == swiotlb_virt_to_bus(hwdev, io_tlb_overflow_buffer));
-}
-EXPORT_SYMBOL(swiotlb_dma_mapping_error);
-
-/*
- * Return whether the given device DMA address mask can be supported
- * properly. For example, if your device can only drive the low 24-bits
- * during bus mastering, then you would pass 0x00ffffff as the mask to
- * this function.
- */
-int
-swiotlb_dma_supported(struct device *hwdev, u64 mask)
-{
- return swiotlb_virt_to_bus(hwdev, io_tlb_end - 1) <= mask;
-}
-EXPORT_SYMBOL(swiotlb_dma_supported);
--
1.6.2.5
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