dma-mapping: move all DMA mapping code to kernel/dma

Currently the code is split over various files with dma- prefixes in the
lib/ and drives/base directories, and the number of files keeps growing.
Move them into a single directory to keep the code together and remove
the file name prefixes.  To match the irq infrastructure this directory
is placed under the kernel/ directory.

Signed-off-by: Christoph Hellwig <hch@lst.de>

7 files changed, 1 insertions, 3279 deletions

diff --git a/lib/Kconfig b/lib/Kconfig
index 809fdd1..803fcbc 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -420,60 +420,15 @@ config HAS_IOPORT_MAP
 	depends on HAS_IOMEM && !NO_IOPORT_MAP
 	default y
 
-config HAS_DMA
-	bool
-	depends on !NO_DMA
-	default y
+source "kernel/dma/Kconfig"
 
 config SGL_ALLOC
 	bool
 	default n
 
-config NEED_SG_DMA_LENGTH
-	bool
-
-config NEED_DMA_MAP_STATE
-	bool
-
-config ARCH_DMA_ADDR_T_64BIT
-	def_bool 64BIT || PHYS_ADDR_T_64BIT
-
 config IOMMU_HELPER
 	bool
 
-config ARCH_HAS_SYNC_DMA_FOR_DEVICE
-	bool
-
-config ARCH_HAS_SYNC_DMA_FOR_CPU
-	bool
-	select NEED_DMA_MAP_STATE
-
-config DMA_DIRECT_OPS
-	bool
-	depends on HAS_DMA
-
-config DMA_NONCOHERENT_OPS
-	bool
-	depends on HAS_DMA
-	select DMA_DIRECT_OPS
-
-config DMA_NONCOHERENT_MMAP
-	bool
-	depends on DMA_NONCOHERENT_OPS
-
-config DMA_NONCOHERENT_CACHE_SYNC
-	bool
-	depends on DMA_NONCOHERENT_OPS
-
-config DMA_VIRT_OPS
-	bool
-	depends on HAS_DMA
-
-config SWIOTLB
-	bool
-	select DMA_DIRECT_OPS
-	select NEED_DMA_MAP_STATE
-
 config CHECK_SIGNATURE
 	bool
 
diff --git a/lib/Makefile b/lib/Makefile
index 5e0e160..8153fda 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -29,9 +29,6 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
 lib-$(CONFIG_PRINTK) += dump_stack.o
 lib-$(CONFIG_MMU) += ioremap.o
 lib-$(CONFIG_SMP) += cpumask.o
-obj-$(CONFIG_DMA_DIRECT_OPS) += dma-direct.o
-obj-$(CONFIG_DMA_NONCOHERENT_OPS) += dma-noncoherent.o
-obj-$(CONFIG_DMA_VIRT_OPS) += dma-virt.o
 
 lib-y	+= kobject.o klist.o
 obj-y	+= lockref.o
@@ -148,7 +145,6 @@ obj-$(CONFIG_SMP) += percpu_counter.o
 obj-$(CONFIG_AUDIT_GENERIC) += audit.o
 obj-$(CONFIG_AUDIT_COMPAT_GENERIC) += compat_audit.o
 
-obj-$(CONFIG_SWIOTLB) += swiotlb.o
 obj-$(CONFIG_IOMMU_HELPER) += iommu-helper.o
 obj-$(CONFIG_FAULT_INJECTION) += fault-inject.o
 obj-$(CONFIG_NOTIFIER_ERROR_INJECTION) += notifier-error-inject.o
@@ -169,8 +165,6 @@ obj-$(CONFIG_NLATTR) += nlattr.o
 
 obj-$(CONFIG_LRU_CACHE) += lru_cache.o
 
-obj-$(CONFIG_DMA_API_DEBUG) += dma-debug.o
-
 obj-$(CONFIG_GENERIC_CSUM) += checksum.o
 
 obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
deleted file mode 100644
index c007d25..0000000
--- a/lib/dma-debug.c
+++ /dev/null
@@ -1,1773 +0,0 @@
-/*
- * Copyright (C) 2008 Advanced Micro Devices, Inc.
- *
- * Author: Joerg Roedel <joerg.roedel@amd.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published
- * by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- */
-
-#include <linux/sched/task_stack.h>
-#include <linux/scatterlist.h>
-#include <linux/dma-mapping.h>
-#include <linux/sched/task.h>
-#include <linux/stacktrace.h>
-#include <linux/dma-debug.h>
-#include <linux/spinlock.h>
-#include <linux/vmalloc.h>
-#include <linux/debugfs.h>
-#include <linux/uaccess.h>
-#include <linux/export.h>
-#include <linux/device.h>
-#include <linux/types.h>
-#include <linux/sched.h>
-#include <linux/ctype.h>
-#include <linux/list.h>
-#include <linux/slab.h>
-
-#include <asm/sections.h>
-
-#define HASH_SIZE       1024ULL
-#define HASH_FN_SHIFT   13
-#define HASH_FN_MASK    (HASH_SIZE - 1)
-
-/* allow architectures to override this if absolutely required */
-#ifndef PREALLOC_DMA_DEBUG_ENTRIES
-#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
-#endif
-
-enum {
-	dma_debug_single,
-	dma_debug_page,
-	dma_debug_sg,
-	dma_debug_coherent,
-	dma_debug_resource,
-};
-
-enum map_err_types {
-	MAP_ERR_CHECK_NOT_APPLICABLE,
-	MAP_ERR_NOT_CHECKED,
-	MAP_ERR_CHECKED,
-};
-
-#define DMA_DEBUG_STACKTRACE_ENTRIES 5
-
-/**
- * struct dma_debug_entry - track a dma_map* or dma_alloc_coherent mapping
- * @list: node on pre-allocated free_entries list
- * @dev: 'dev' argument to dma_map_{page|single|sg} or dma_alloc_coherent
- * @type: single, page, sg, coherent
- * @pfn: page frame of the start address
- * @offset: offset of mapping relative to pfn
- * @size: length of the mapping
- * @direction: enum dma_data_direction
- * @sg_call_ents: 'nents' from dma_map_sg
- * @sg_mapped_ents: 'mapped_ents' from dma_map_sg
- * @map_err_type: track whether dma_mapping_error() was checked
- * @stacktrace: support backtraces when a violation is detected
- */
-struct dma_debug_entry {
-	struct list_head list;
-	struct device    *dev;
-	int              type;
-	unsigned long	 pfn;
-	size_t		 offset;
-	u64              dev_addr;
-	u64              size;
-	int              direction;
-	int		 sg_call_ents;
-	int		 sg_mapped_ents;
-	enum map_err_types  map_err_type;
-#ifdef CONFIG_STACKTRACE
-	struct		 stack_trace stacktrace;
-	unsigned long	 st_entries[DMA_DEBUG_STACKTRACE_ENTRIES];
-#endif
-};
-
-typedef bool (*match_fn)(struct dma_debug_entry *, struct dma_debug_entry *);
-
-struct hash_bucket {
-	struct list_head list;
-	spinlock_t lock;
-} ____cacheline_aligned_in_smp;
-
-/* Hash list to save the allocated dma addresses */
-static struct hash_bucket dma_entry_hash[HASH_SIZE];
-/* List of pre-allocated dma_debug_entry's */
-static LIST_HEAD(free_entries);
-/* Lock for the list above */
-static DEFINE_SPINLOCK(free_entries_lock);
-
-/* Global disable flag - will be set in case of an error */
-static bool global_disable __read_mostly;
-
-/* Early initialization disable flag, set at the end of dma_debug_init */
-static bool dma_debug_initialized __read_mostly;
-
-static inline bool dma_debug_disabled(void)
-{
-	return global_disable || !dma_debug_initialized;
-}
-
-/* Global error count */
-static u32 error_count;
-
-/* Global error show enable*/
-static u32 show_all_errors __read_mostly;
-/* Number of errors to show */
-static u32 show_num_errors = 1;
-
-static u32 num_free_entries;
-static u32 min_free_entries;
-static u32 nr_total_entries;
-
-/* number of preallocated entries requested by kernel cmdline */
-static u32 nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES;
-
-/* debugfs dentry's for the stuff above */
-static struct dentry *dma_debug_dent        __read_mostly;
-static struct dentry *global_disable_dent   __read_mostly;
-static struct dentry *error_count_dent      __read_mostly;
-static struct dentry *show_all_errors_dent  __read_mostly;
-static struct dentry *show_num_errors_dent  __read_mostly;
-static struct dentry *num_free_entries_dent __read_mostly;
-static struct dentry *min_free_entries_dent __read_mostly;
-static struct dentry *filter_dent           __read_mostly;
-
-/* per-driver filter related state */
-
-#define NAME_MAX_LEN	64
-
-static char                  current_driver_name[NAME_MAX_LEN] __read_mostly;
-static struct device_driver *current_driver                    __read_mostly;
-
-static DEFINE_RWLOCK(driver_name_lock);
-
-static const char *const maperr2str[] = {
-	[MAP_ERR_CHECK_NOT_APPLICABLE] = "dma map error check not applicable",
-	[MAP_ERR_NOT_CHECKED] = "dma map error not checked",
-	[MAP_ERR_CHECKED] = "dma map error checked",
-};
-
-static const char *type2name[5] = { "single", "page",
-				    "scather-gather", "coherent",
-				    "resource" };
-
-static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
-				   "DMA_FROM_DEVICE", "DMA_NONE" };
-
-/*
- * The access to some variables in this macro is racy. We can't use atomic_t
- * here because all these variables are exported to debugfs. Some of them even
- * writeable. This is also the reason why a lock won't help much. But anyway,
- * the races are no big deal. Here is why:
- *
- *   error_count: the addition is racy, but the worst thing that can happen is
- *                that we don't count some errors
- *   show_num_errors: the subtraction is racy. Also no big deal because in
- *                    worst case this will result in one warning more in the
- *                    system log than the user configured. This variable is
- *                    writeable via debugfs.
- */
-static inline void dump_entry_trace(struct dma_debug_entry *entry)
-{
-#ifdef CONFIG_STACKTRACE
-	if (entry) {
-		pr_warning("Mapped at:\n");
-		print_stack_trace(&entry->stacktrace, 0);
-	}
-#endif
-}
-
-static bool driver_filter(struct device *dev)
-{
-	struct device_driver *drv;
-	unsigned long flags;
-	bool ret;
-
-	/* driver filter off */
-	if (likely(!current_driver_name[0]))
-		return true;
-
-	/* driver filter on and initialized */
-	if (current_driver && dev && dev->driver == current_driver)
-		return true;
-
-	/* driver filter on, but we can't filter on a NULL device... */
-	if (!dev)
-		return false;
-
-	if (current_driver || !current_driver_name[0])
-		return false;
-
-	/* driver filter on but not yet initialized */
-	drv = dev->driver;
-	if (!drv)
-		return false;
-
-	/* lock to protect against change of current_driver_name */
-	read_lock_irqsave(&driver_name_lock, flags);
-
-	ret = false;
-	if (drv->name &&
-	    strncmp(current_driver_name, drv->name, NAME_MAX_LEN - 1) == 0) {
-		current_driver = drv;
-		ret = true;
-	}
-
-	read_unlock_irqrestore(&driver_name_lock, flags);
-
-	return ret;
-}
-
-#define err_printk(dev, entry, format, arg...) do {			\
-		error_count += 1;					\
-		if (driver_filter(dev) &&				\
-		    (show_all_errors || show_num_errors > 0)) {		\
-			WARN(1, "%s %s: " format,			\
-			     dev ? dev_driver_string(dev) : "NULL",	\
-			     dev ? dev_name(dev) : "NULL", ## arg);	\
-			dump_entry_trace(entry);			\
-		}							\
-		if (!show_all_errors && show_num_errors > 0)		\
-			show_num_errors -= 1;				\
-	} while (0);
-
-/*
- * Hash related functions
- *
- * Every DMA-API request is saved into a struct dma_debug_entry. To
- * have quick access to these structs they are stored into a hash.
- */
-static int hash_fn(struct dma_debug_entry *entry)
-{
-	/*
-	 * Hash function is based on the dma address.
-	 * We use bits 20-27 here as the index into the hash
-	 */
-	return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK;
-}
-
-/*
- * Request exclusive access to a hash bucket for a given dma_debug_entry.
- */
-static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry,
-					   unsigned long *flags)
-	__acquires(&dma_entry_hash[idx].lock)
-{
-	int idx = hash_fn(entry);
-	unsigned long __flags;
-
-	spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags);
-	*flags = __flags;
-	return &dma_entry_hash[idx];
-}
-
-/*
- * Give up exclusive access to the hash bucket
- */
-static void put_hash_bucket(struct hash_bucket *bucket,
-			    unsigned long *flags)
-	__releases(&bucket->lock)
-{
-	unsigned long __flags = *flags;
-
-	spin_unlock_irqrestore(&bucket->lock, __flags);
-}
-
-static bool exact_match(struct dma_debug_entry *a, struct dma_debug_entry *b)
-{
-	return ((a->dev_addr == b->dev_addr) &&
-		(a->dev == b->dev)) ? true : false;
-}
-
-static bool containing_match(struct dma_debug_entry *a,
-			     struct dma_debug_entry *b)
-{
-	if (a->dev != b->dev)
-		return false;
-
-	if ((b->dev_addr <= a->dev_addr) &&
-	    ((b->dev_addr + b->size) >= (a->dev_addr + a->size)))
-		return true;
-
-	return false;
-}
-
-/*
- * Search a given entry in the hash bucket list
- */
-static struct dma_debug_entry *__hash_bucket_find(struct hash_bucket *bucket,
-						  struct dma_debug_entry *ref,
-						  match_fn match)
-{
-	struct dma_debug_entry *entry, *ret = NULL;
-	int matches = 0, match_lvl, last_lvl = -1;
-
-	list_for_each_entry(entry, &bucket->list, list) {
-		if (!match(ref, entry))
-			continue;
-
-		/*
-		 * Some drivers map the same physical address multiple
-		 * times. Without a hardware IOMMU this results in the
-		 * same device addresses being put into the dma-debug
-		 * hash multiple times too. This can result in false
-		 * positives being reported. Therefore we implement a
-		 * best-fit algorithm here which returns the entry from
-		 * the hash which fits best to the reference value
-		 * instead of the first-fit.
-		 */
-		matches += 1;
-		match_lvl = 0;
-		entry->size         == ref->size         ? ++match_lvl : 0;
-		entry->type         == ref->type         ? ++match_lvl : 0;
-		entry->direction    == ref->direction    ? ++match_lvl : 0;
-		entry->sg_call_ents == ref->sg_call_ents ? ++match_lvl : 0;
-
-		if (match_lvl == 4) {
-			/* perfect-fit - return the result */
-			return entry;
-		} else if (match_lvl > last_lvl) {
-			/*
-			 * We found an entry that fits better then the
-			 * previous one or it is the 1st match.
-			 */
-			last_lvl = match_lvl;
-			ret      = entry;
-		}
-	}
-
-	/*
-	 * If we have multiple matches but no perfect-fit, just return
-	 * NULL.
-	 */
-	ret = (matches == 1) ? ret : NULL;
-
-	return ret;
-}
-
-static struct dma_debug_entry *bucket_find_exact(struct hash_bucket *bucket,
-						 struct dma_debug_entry *ref)
-{
-	return __hash_bucket_find(bucket, ref, exact_match);
-}
-
-static struct dma_debug_entry *bucket_find_contain(struct hash_bucket **bucket,
-						   struct dma_debug_entry *ref,
-						   unsigned long *flags)
-{
-
-	unsigned int max_range = dma_get_max_seg_size(ref->dev);
-	struct dma_debug_entry *entry, index = *ref;
-	unsigned int range = 0;
-
-	while (range <= max_range) {
-		entry = __hash_bucket_find(*bucket, ref, containing_match);
-
-		if (entry)
-			return entry;
-
-		/*
-		 * Nothing found, go back a hash bucket
-		 */
-		put_hash_bucket(*bucket, flags);
-		range          += (1 << HASH_FN_SHIFT);
-		index.dev_addr -= (1 << HASH_FN_SHIFT);
-		*bucket = get_hash_bucket(&index, flags);
-	}
-
-	return NULL;
-}
-
-/*
- * Add an entry to a hash bucket
- */
-static void hash_bucket_add(struct hash_bucket *bucket,
-			    struct dma_debug_entry *entry)
-{
-	list_add_tail(&entry->list, &bucket->list);
-}
-
-/*
- * Remove entry from a hash bucket list
- */
-static void hash_bucket_del(struct dma_debug_entry *entry)
-{
-	list_del(&entry->list);
-}
-
-static unsigned long long phys_addr(struct dma_debug_entry *entry)
-{
-	if (entry->type == dma_debug_resource)
-		return __pfn_to_phys(entry->pfn) + entry->offset;
-
-	return page_to_phys(pfn_to_page(entry->pfn)) + entry->offset;
-}
-
-/*
- * Dump mapping entries for debugging purposes
- */
-void debug_dma_dump_mappings(struct device *dev)
-{
-	int idx;
-
-	for (idx = 0; idx < HASH_SIZE; idx++) {
-		struct hash_bucket *bucket = &dma_entry_hash[idx];
-		struct dma_debug_entry *entry;
-		unsigned long flags;
-
-		spin_lock_irqsave(&bucket->lock, flags);
-
-		list_for_each_entry(entry, &bucket->list, list) {
-			if (!dev || dev == entry->dev) {
-				dev_info(entry->dev,
-					 "%s idx %d P=%Lx N=%lx D=%Lx L=%Lx %s %s\n",
-					 type2name[entry->type], idx,
-					 phys_addr(entry), entry->pfn,
-					 entry->dev_addr, entry->size,
-					 dir2name[entry->direction],
-					 maperr2str[entry->map_err_type]);
-			}
-		}
-
-		spin_unlock_irqrestore(&bucket->lock, flags);
-	}
-}
-
-/*
- * For each mapping (initial cacheline in the case of
- * dma_alloc_coherent/dma_map_page, initial cacheline in each page of a
- * scatterlist, or the cacheline specified in dma_map_single) insert
- * into this tree using the cacheline as the key. At
- * dma_unmap_{single|sg|page} or dma_free_coherent delete the entry.  If
- * the entry already exists at insertion time add a tag as a reference
- * count for the overlapping mappings.  For now, the overlap tracking
- * just ensures that 'unmaps' balance 'maps' before marking the
- * cacheline idle, but we should also be flagging overlaps as an API
- * violation.
- *
- * Memory usage is mostly constrained by the maximum number of available
- * dma-debug entries in that we need a free dma_debug_entry before
- * inserting into the tree.  In the case of dma_map_page and
- * dma_alloc_coherent there is only one dma_debug_entry and one
- * dma_active_cacheline entry to track per event.  dma_map_sg(), on the
- * other hand, consumes a single dma_debug_entry, but inserts 'nents'
- * entries into the tree.
- *
- * At any time debug_dma_assert_idle() can be called to trigger a
- * warning if any cachelines in the given page are in the active set.
- */
-static RADIX_TREE(dma_active_cacheline, GFP_NOWAIT);
-static DEFINE_SPINLOCK(radix_lock);
-#define ACTIVE_CACHELINE_MAX_OVERLAP ((1 << RADIX_TREE_MAX_TAGS) - 1)
-#define CACHELINE_PER_PAGE_SHIFT (PAGE_SHIFT - L1_CACHE_SHIFT)
-#define CACHELINES_PER_PAGE (1 << CACHELINE_PER_PAGE_SHIFT)
-
-static phys_addr_t to_cacheline_number(struct dma_debug_entry *entry)
-{
-	return (entry->pfn << CACHELINE_PER_PAGE_SHIFT) +
-		(entry->offset >> L1_CACHE_SHIFT);
-}
-
-static int active_cacheline_read_overlap(phys_addr_t cln)
-{
-	int overlap = 0, i;
-
-	for (i = RADIX_TREE_MAX_TAGS - 1; i >= 0; i--)
-		if (radix_tree_tag_get(&dma_active_cacheline, cln, i))
-			overlap |= 1 << i;
-	return overlap;
-}
-
-static int active_cacheline_set_overlap(phys_addr_t cln, int overlap)
-{
-	int i;
-
-	if (overlap > ACTIVE_CACHELINE_MAX_OVERLAP || overlap < 0)
-		return overlap;
-
-	for (i = RADIX_TREE_MAX_TAGS - 1; i >= 0; i--)
-		if (overlap & 1 << i)
-			radix_tree_tag_set(&dma_active_cacheline, cln, i);
-		else
-			radix_tree_tag_clear(&dma_active_cacheline, cln, i);
-
-	return overlap;
-}
-
-static void active_cacheline_inc_overlap(phys_addr_t cln)
-{
-	int overlap = active_cacheline_read_overlap(cln);
-
-	overlap = active_cacheline_set_overlap(cln, ++overlap);
-
-	/* If we overflowed the overlap counter then we're potentially
-	 * leaking dma-mappings.  Otherwise, if maps and unmaps are
-	 * balanced then this overflow may cause false negatives in
-	 * debug_dma_assert_idle() as the cacheline may be marked idle
-	 * prematurely.
-	 */
-	WARN_ONCE(overlap > ACTIVE_CACHELINE_MAX_OVERLAP,
-		  "DMA-API: exceeded %d overlapping mappings of cacheline %pa\n",
-		  ACTIVE_CACHELINE_MAX_OVERLAP, &cln);
-}
-
-static int active_cacheline_dec_overlap(phys_addr_t cln)
-{
-	int overlap = active_cacheline_read_overlap(cln);
-
-	return active_cacheline_set_overlap(cln, --overlap);
-}
-
-static int active_cacheline_insert(struct dma_debug_entry *entry)
-{
-	phys_addr_t cln = to_cacheline_number(entry);
-	unsigned long flags;
-	int rc;
-
-	/* If the device is not writing memory then we don't have any
-	 * concerns about the cpu consuming stale data.  This mitigates
-	 * legitimate usages of overlapping mappings.
-	 */
-	if (entry->direction == DMA_TO_DEVICE)
-		return 0;
-
-	spin_lock_irqsave(&radix_lock, flags);
-	rc = radix_tree_insert(&dma_active_cacheline, cln, entry);
-	if (rc == -EEXIST)
-		active_cacheline_inc_overlap(cln);
-	spin_unlock_irqrestore(&radix_lock, flags);
-
-	return rc;
-}
-
-static void active_cacheline_remove(struct dma_debug_entry *entry)
-{
-	phys_addr_t cln = to_cacheline_number(entry);
-	unsigned long flags;
-
-	/* ...mirror the insert case */
-	if (entry->direction == DMA_TO_DEVICE)
-		return;
-
-	spin_lock_irqsave(&radix_lock, flags);
-	/* since we are counting overlaps the final put of the
-	 * cacheline will occur when the overlap count is 0.
-	 * active_cacheline_dec_overlap() returns -1 in that case
-	 */
-	if (active_cacheline_dec_overlap(cln) < 0)
-		radix_tree_delete(&dma_active_cacheline, cln);
-	spin_unlock_irqrestore(&radix_lock, flags);
-}
-
-/**
- * debug_dma_assert_idle() - assert that a page is not undergoing dma
- * @page: page to lookup in the dma_active_cacheline tree
- *
- * Place a call to this routine in cases where the cpu touching the page
- * before the dma completes (page is dma_unmapped) will lead to data
- * corruption.
- */
-void debug_dma_assert_idle(struct page *page)
-{
-	static struct dma_debug_entry *ents[CACHELINES_PER_PAGE];
-	struct dma_debug_entry *entry = NULL;
-	void **results = (void **) &ents;
-	unsigned int nents, i;
-	unsigned long flags;
-	phys_addr_t cln;
-
-	if (dma_debug_disabled())
-		return;
-
-	if (!page)
-		return;
-
-	cln = (phys_addr_t) page_to_pfn(page) << CACHELINE_PER_PAGE_SHIFT;
-	spin_lock_irqsave(&radix_lock, flags);
-	nents = radix_tree_gang_lookup(&dma_active_cacheline, results, cln,
-				       CACHELINES_PER_PAGE);
-	for (i = 0; i < nents; i++) {
-		phys_addr_t ent_cln = to_cacheline_number(ents[i]);
-
-		if (ent_cln == cln) {
-			entry = ents[i];
-			break;
-		} else if (ent_cln >= cln + CACHELINES_PER_PAGE)
-			break;
-	}
-	spin_unlock_irqrestore(&radix_lock, flags);
-
-	if (!entry)
-		return;
-
-	cln = to_cacheline_number(entry);
-	err_printk(entry->dev, entry,
-		   "DMA-API: cpu touching an active dma mapped cacheline [cln=%pa]\n",
-		   &cln);
-}
-
-/*
- * Wrapper function for adding an entry to the hash.
- * This function takes care of locking itself.
- */
-static void add_dma_entry(struct dma_debug_entry *entry)
-{
-	struct hash_bucket *bucket;
-	unsigned long flags;
-	int rc;
-
-	bucket = get_hash_bucket(entry, &flags);
-	hash_bucket_add(bucket, entry);
-	put_hash_bucket(bucket, &flags);
-
-	rc = active_cacheline_insert(entry);
-	if (rc == -ENOMEM) {
-		pr_err("DMA-API: cacheline tracking ENOMEM, dma-debug disabled\n");
-		global_disable = true;
-	}
-
-	/* TODO: report -EEXIST errors here as overlapping mappings are
-	 * not supported by the DMA API
-	 */
-}
-
-static struct dma_debug_entry *__dma_entry_alloc(void)
-{
-	struct dma_debug_entry *entry;
-
-	entry = list_entry(free_entries.next, struct dma_debug_entry, list);
-	list_del(&entry->list);
-	memset(entry, 0, sizeof(*entry));
-
-	num_free_entries -= 1;
-	if (num_free_entries < min_free_entries)
-		min_free_entries = num_free_entries;
-
-	return entry;
-}
-
-/* struct dma_entry allocator
- *
- * The next two functions implement the allocator for
- * struct dma_debug_entries.
- */
-static struct dma_debug_entry *dma_entry_alloc(void)
-{
-	struct dma_debug_entry *entry;
-	unsigned long flags;
-
-	spin_lock_irqsave(&free_entries_lock, flags);
-
-	if (list_empty(&free_entries)) {
-		global_disable = true;
-		spin_unlock_irqrestore(&free_entries_lock, flags);
-		pr_err("DMA-API: debugging out of memory - disabling\n");
-		return NULL;
-	}
-
-	entry = __dma_entry_alloc();
-
-	spin_unlock_irqrestore(&free_entries_lock, flags);
-
-#ifdef CONFIG_STACKTRACE
-	entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES;
-	entry->stacktrace.entries = entry->st_entries;
-	entry->stacktrace.skip = 2;
-	save_stack_trace(&entry->stacktrace);
-#endif
-
-	return entry;
-}
-
-static void dma_entry_free(struct dma_debug_entry *entry)
-{
-	unsigned long flags;
-
-	active_cacheline_remove(entry);
-
-	/*
-	 * add to beginning of the list - this way the entries are
-	 * more likely cache hot when they are reallocated.
-	 */
-	spin_lock_irqsave(&free_entries_lock, flags);
-	list_add(&entry->list, &free_entries);
-	num_free_entries += 1;
-	spin_unlock_irqrestore(&free_entries_lock, flags);
-}
-
-int dma_debug_resize_entries(u32 num_entries)
-{
-	int i, delta, ret = 0;
-	unsigned long flags;
-	struct dma_debug_entry *entry;
-	LIST_HEAD(tmp);
-
-	spin_lock_irqsave(&free_entries_lock, flags);
-
-	if (nr_total_entries < num_entries) {
-		delta = num_entries - nr_total_entries;
-
-		spin_unlock_irqrestore(&free_entries_lock, flags);
-
-		for (i = 0; i < delta; i++) {
-			entry = kzalloc(sizeof(*entry), GFP_KERNEL);
-			if (!entry)
-				break;
-
-			list_add_tail(&entry->list, &tmp);
-		}
-
-		spin_lock_irqsave(&free_entries_lock, flags);
-
-		list_splice(&tmp, &free_entries);
-		nr_total_entries += i;
-		num_free_entries += i;
-	} else {
-		delta = nr_total_entries - num_entries;
-
-		for (i = 0; i < delta && !list_empty(&free_entries); i++) {
-			entry = __dma_entry_alloc();
-			kfree(entry);
-		}
-
-		nr_total_entries -= i;
-	}
-
-	if (nr_total_entries != num_entries)
-		ret = 1;
-
-	spin_unlock_irqrestore(&free_entries_lock, flags);
-
-	return ret;
-}
-
-/*
- * DMA-API debugging init code
- *
- * The init code does two things:
- *   1. Initialize core data structures
- *   2. Preallocate a given number of dma_debug_entry structs
- */
-
-static int prealloc_memory(u32 num_entries)
-{
-	struct dma_debug_entry *entry, *next_entry;
-	int i;
-
-	for (i = 0; i < num_entries; ++i) {
-		entry = kzalloc(sizeof(*entry), GFP_KERNEL);
-		if (!entry)
-			goto out_err;
-
-		list_add_tail(&entry->list, &free_entries);
-	}
-
-	num_free_entries = num_entries;
-	min_free_entries = num_entries;
-
-	pr_info("DMA-API: preallocated %d debug entries\n", num_entries);
-
-	return 0;
-
-out_err:
-
-	list_for_each_entry_safe(entry, next_entry, &free_entries, list) {
-		list_del(&entry->list);
-		kfree(entry);
-	}
-
-	return -ENOMEM;
-}
-
-static ssize_t filter_read(struct file *file, char __user *user_buf,
-			   size_t count, loff_t *ppos)
-{
-	char buf[NAME_MAX_LEN + 1];
-	unsigned long flags;
-	int len;
-
-	if (!current_driver_name[0])
-		return 0;
-
-	/*
-	 * We can't copy to userspace directly because current_driver_name can
-	 * only be read under the driver_name_lock with irqs disabled. So
-	 * create a temporary copy first.
-	 */
-	read_lock_irqsave(&driver_name_lock, flags);
-	len = scnprintf(buf, NAME_MAX_LEN + 1, "%s\n", current_driver_name);
-	read_unlock_irqrestore(&driver_name_lock, flags);
-
-	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
-}
-
-static ssize_t filter_write(struct file *file, const char __user *userbuf,
-			    size_t count, loff_t *ppos)
-{
-	char buf[NAME_MAX_LEN];
-	unsigned long flags;
-	size_t len;
-	int i;
-
-	/*
-	 * We can't copy from userspace directly. Access to
-	 * current_driver_name is protected with a write_lock with irqs
-	 * disabled. Since copy_from_user can fault and may sleep we
-	 * need to copy to temporary buffer first
-	 */
-	len = min(count, (size_t)(NAME_MAX_LEN - 1));
-	if (copy_from_user(buf, userbuf, len))
-		return -EFAULT;
-
-	buf[len] = 0;
-
-	write_lock_irqsave(&driver_name_lock, flags);
-
-	/*
-	 * Now handle the string we got from userspace very carefully.
-	 * The rules are:
-	 *         - only use the first token we got
-	 *         - token delimiter is everything looking like a space
-	 *           character (' ', '\n', '\t' ...)
-	 *
-	 */
-	if (!isalnum(buf[0])) {
-		/*
-		 * If the first character userspace gave us is not
-		 * alphanumerical then assume the filter should be
-		 * switched off.
-		 */
-		if (current_driver_name[0])
-			pr_info("DMA-API: switching off dma-debug driver filter\n");
-		current_driver_name[0] = 0;
-		current_driver = NULL;
-		goto out_unlock;
-	}
-
-	/*
-	 * Now parse out the first token and use it as the name for the
-	 * driver to filter for.
-	 */
-	for (i = 0; i < NAME_MAX_LEN - 1; ++i) {
-		current_driver_name[i] = buf[i];
-		if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0)
-			break;
-	}
-	current_driver_name[i] = 0;
-	current_driver = NULL;
-
-	pr_info("DMA-API: enable driver filter for driver [%s]\n",
-		current_driver_name);
-
-out_unlock:
-	write_unlock_irqrestore(&driver_name_lock, flags);
-
-	return count;
-}
-
-static const struct file_operations filter_fops = {
-	.read  = filter_read,
-	.write = filter_write,
-	.llseek = default_llseek,
-};
-
-static int dma_debug_fs_init(void)
-{
-	dma_debug_dent = debugfs_create_dir("dma-api", NULL);
-	if (!dma_debug_dent) {
-		pr_err("DMA-API: can not create debugfs directory\n");
-		return -ENOMEM;
-	}
-
-	global_disable_dent = debugfs_create_bool("disabled", 0444,
-			dma_debug_dent,
-			&global_disable);
-	if (!global_disable_dent)
-		goto out_err;
-
-	error_count_dent = debugfs_create_u32("error_count", 0444,
-			dma_debug_dent, &error_count);
-	if (!error_count_dent)
-		goto out_err;
-
-	show_all_errors_dent = debugfs_create_u32("all_errors", 0644,
-			dma_debug_dent,
-			&show_all_errors);
-	if (!show_all_errors_dent)
-		goto out_err;
-
-	show_num_errors_dent = debugfs_create_u32("num_errors", 0644,
-			dma_debug_dent,
-			&show_num_errors);
-	if (!show_num_errors_dent)
-		goto out_err;
-
-	num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444,
-			dma_debug_dent,
-			&num_free_entries);
-	if (!num_free_entries_dent)
-		goto out_err;
-
-	min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444,
-			dma_debug_dent,
-			&min_free_entries);
-	if (!min_free_entries_dent)
-		goto out_err;
-
-	filter_dent = debugfs_create_file("driver_filter", 0644,
-					  dma_debug_dent, NULL, &filter_fops);
-	if (!filter_dent)
-		goto out_err;
-
-	return 0;
-
-out_err:
-	debugfs_remove_recursive(dma_debug_dent);
-
-	return -ENOMEM;
-}
-
-static int device_dma_allocations(struct device *dev, struct dma_debug_entry **out_entry)
-{
-	struct dma_debug_entry *entry;
-	unsigned long flags;
-	int count = 0, i;
-
-	for (i = 0; i < HASH_SIZE; ++i) {
-		spin_lock_irqsave(&dma_entry_hash[i].lock, flags);
-		list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
-			if (entry->dev == dev) {
-				count += 1;
-				*out_entry = entry;
-			}
-		}
-		spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags);
-	}
-
-	return count;
-}
-
-static int dma_debug_device_change(struct notifier_block *nb, unsigned long action, void *data)
-{
-	struct device *dev = data;
-	struct dma_debug_entry *uninitialized_var(entry);
-	int count;
-
-	if (dma_debug_disabled())
-		return 0;
-
-	switch (action) {
-	case BUS_NOTIFY_UNBOUND_DRIVER:
-		count = device_dma_allocations(dev, &entry);
-		if (count == 0)
-			break;
-		err_printk(dev, entry, "DMA-API: device driver has pending "
-				"DMA allocations while released from device "
-				"[count=%d]\n"
-				"One of leaked entries details: "
-				"[device address=0x%016llx] [size=%llu bytes] "
-				"[mapped with %s] [mapped as %s]\n",
-			count, entry->dev_addr, entry->size,
-			dir2name[entry->direction], type2name[entry->type]);
-		break;
-	default:
-		break;
-	}
-
-	return 0;
-}
-
-void dma_debug_add_bus(struct bus_type *bus)
-{
-	struct notifier_block *nb;
-
-	if (dma_debug_disabled())
-		return;
-
-	nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
-	if (nb == NULL) {
-		pr_err("dma_debug_add_bus: out of memory\n");
-		return;
-	}
-
-	nb->notifier_call = dma_debug_device_change;
-
-	bus_register_notifier(bus, nb);
-}
-
-static int dma_debug_init(void)
-{
-	int i;
-
-	/* Do not use dma_debug_initialized here, since we really want to be
-	 * called to set dma_debug_initialized
-	 */
-	if (global_disable)
-		return 0;
-
-	for (i = 0; i < HASH_SIZE; ++i) {
-		INIT_LIST_HEAD(&dma_entry_hash[i].list);
-		spin_lock_init(&dma_entry_hash[i].lock);
-	}
-
-	if (dma_debug_fs_init() != 0) {
-		pr_err("DMA-API: error creating debugfs entries - disabling\n");
-		global_disable = true;
-
-		return 0;
-	}
-
-	if (prealloc_memory(nr_prealloc_entries) != 0) {
-		pr_err("DMA-API: debugging out of memory error - disabled\n");
-		global_disable = true;
-
-		return 0;
-	}
-
-	nr_total_entries = num_free_entries;
-
-	dma_debug_initialized = true;
-
-	pr_info("DMA-API: debugging enabled by kernel config\n");
-	return 0;
-}
-core_initcall(dma_debug_init);
-
-static __init int dma_debug_cmdline(char *str)
-{
-	if (!str)
-		return -EINVAL;
-
-	if (strncmp(str, "off", 3) == 0) {
-		pr_info("DMA-API: debugging disabled on kernel command line\n");
-		global_disable = true;
-	}
-
-	return 0;
-}
-
-static __init int dma_debug_entries_cmdline(char *str)
-{
-	if (!str)
-		return -EINVAL;
-	if (!get_option(&str, &nr_prealloc_entries))
-		nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES;
-	return 0;
-}
-
-__setup("dma_debug=", dma_debug_cmdline);
-__setup("dma_debug_entries=", dma_debug_entries_cmdline);
-
-static void check_unmap(struct dma_debug_entry *ref)
-{
-	struct dma_debug_entry *entry;
-	struct hash_bucket *bucket;
-	unsigned long flags;
-
-	bucket = get_hash_bucket(ref, &flags);
-	entry = bucket_find_exact(bucket, ref);
-
-	if (!entry) {
-		/* must drop lock before calling dma_mapping_error */
-		put_hash_bucket(bucket, &flags);
-
-		if (dma_mapping_error(ref->dev, ref->dev_addr)) {
-			err_printk(ref->dev, NULL,
-				   "DMA-API: device driver tries to free an "
-				   "invalid DMA memory address\n");
-		} else {
-			err_printk(ref->dev, NULL,
-				   "DMA-API: device driver tries to free DMA "
-				   "memory it has not allocated [device "
-				   "address=0x%016llx] [size=%llu bytes]\n",
-				   ref->dev_addr, ref->size);
-		}
-		return;
-	}
-
-	if (ref->size != entry->size) {
-		err_printk(ref->dev, entry, "DMA-API: device driver frees "
-			   "DMA memory with different size "
-			   "[device address=0x%016llx] [map size=%llu bytes] "
-			   "[unmap size=%llu bytes]\n",
-			   ref->dev_addr, entry->size, ref->size);
-	}
-
-	if (ref->type != entry->type) {
-		err_printk(ref->dev, entry, "DMA-API: device driver frees "
-			   "DMA memory with wrong function "
-			   "[device address=0x%016llx] [size=%llu bytes] "
-			   "[mapped as %s] [unmapped as %s]\n",
-			   ref->dev_addr, ref->size,
-			   type2name[entry->type], type2name[ref->type]);
-	} else if ((entry->type == dma_debug_coherent) &&
-		   (phys_addr(ref) != phys_addr(entry))) {
-		err_printk(ref->dev, entry, "DMA-API: device driver frees "
-			   "DMA memory with different CPU address "
-			   "[device address=0x%016llx] [size=%llu bytes] "
-			   "[cpu alloc address=0x%016llx] "
-			   "[cpu free address=0x%016llx]",
-			   ref->dev_addr, ref->size,
-			   phys_addr(entry),
-			   phys_addr(ref));
-	}
-
-	if (ref->sg_call_ents && ref->type == dma_debug_sg &&
-	    ref->sg_call_ents != entry->sg_call_ents) {
-		err_printk(ref->dev, entry, "DMA-API: device driver frees "
-			   "DMA sg list with different entry count "
-			   "[map count=%d] [unmap count=%d]\n",
-			   entry->sg_call_ents, ref->sg_call_ents);
-	}
-
-	/*
-	 * This may be no bug in reality - but most implementations of the
-	 * DMA API don't handle this properly, so check for it here
-	 */
-	if (ref->direction != entry->direction) {
-		err_printk(ref->dev, entry, "DMA-API: device driver frees "
-			   "DMA memory with different direction "
-			   "[device address=0x%016llx] [size=%llu bytes] "
-			   "[mapped with %s] [unmapped with %s]\n",
-			   ref->dev_addr, ref->size,
-			   dir2name[entry->direction],
-			   dir2name[ref->direction]);
-	}
-
-	/*
-	 * Drivers should use dma_mapping_error() to check the returned
-	 * addresses of dma_map_single() and dma_map_page().
-	 * If not, print this warning message. See Documentation/DMA-API.txt.
-	 */
-	if (entry->map_err_type == MAP_ERR_NOT_CHECKED) {
-		err_printk(ref->dev, entry,
-			   "DMA-API: device driver failed to check map error"
-			   "[device address=0x%016llx] [size=%llu bytes] "
-			   "[mapped as %s]",
-			   ref->dev_addr, ref->size,
-			   type2name[entry->type]);
-	}
-
-	hash_bucket_del(entry);
-	dma_entry_free(entry);
-
-	put_hash_bucket(bucket, &flags);
-}
-
-static void check_for_stack(struct device *dev,
-			    struct page *page, size_t offset)
-{
-	void *addr;
-	struct vm_struct *stack_vm_area = task_stack_vm_area(current);
-
-	if (!stack_vm_area) {
-		/* Stack is direct-mapped. */
-		if (PageHighMem(page))
-			return;
-		addr = page_address(page) + offset;
-		if (object_is_on_stack(addr))
-			err_printk(dev, NULL, "DMA-API: device driver maps memory from stack [addr=%p]\n", addr);
-	} else {
-		/* Stack is vmalloced. */
-		int i;
-
-		for (i = 0; i < stack_vm_area->nr_pages; i++) {
-			if (page != stack_vm_area->pages[i])
-				continue;
-
-			addr = (u8 *)current->stack + i * PAGE_SIZE + offset;
-			err_printk(dev, NULL, "DMA-API: device driver maps memory from stack [probable addr=%p]\n", addr);
-			break;
-		}
-	}
-}
-
-static inline bool overlap(void *addr, unsigned long len, void *start, void *end)
-{
-	unsigned long a1 = (unsigned long)addr;
-	unsigned long b1 = a1 + len;
-	unsigned long a2 = (unsigned long)start;
-	unsigned long b2 = (unsigned long)end;
-
-	return !(b1 <= a2 || a1 >= b2);
-}
-
-static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len)
-{
-	if (overlap(addr, len, _stext, _etext) ||
-	    overlap(addr, len, __start_rodata, __end_rodata))
-		err_printk(dev, NULL, "DMA-API: device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len);
-}
-
-static void check_sync(struct device *dev,
-		       struct dma_debug_entry *ref,
-		       bool to_cpu)
-{
-	struct dma_debug_entry *entry;
-	struct hash_bucket *bucket;
-	unsigned long flags;
-
-	bucket = get_hash_bucket(ref, &flags);
-
-	entry = bucket_find_contain(&bucket, ref, &flags);
-
-	if (!entry) {
-		err_printk(dev, NULL, "DMA-API: device driver tries "
-				"to sync DMA memory it has not allocated "
-				"[device address=0x%016llx] [size=%llu bytes]\n",
-				(unsigned long long)ref->dev_addr, ref->size);
-		goto out;
-	}
-
-	if (ref->size > entry->size) {
-		err_printk(dev, entry, "DMA-API: device driver syncs"
-				" DMA memory outside allocated range "
-				"[device address=0x%016llx] "
-				"[allocation size=%llu bytes] "
-				"[sync offset+size=%llu]\n",
-				entry->dev_addr, entry->size,
-				ref->size);
-	}
-
-	if (entry->direction == DMA_BIDIRECTIONAL)
-		goto out;
-
-	if (ref->direction != entry->direction) {
-		err_printk(dev, entry, "DMA-API: device driver syncs "
-				"DMA memory with different direction "
-				"[device address=0x%016llx] [size=%llu bytes] "
-				"[mapped with %s] [synced with %s]\n",
-				(unsigned long long)ref->dev_addr, entry->size,
-				dir2name[entry->direction],
-				dir2name[ref->direction]);
-	}
-
-	if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
-		      !(ref->direction == DMA_TO_DEVICE))
-		err_printk(dev, entry, "DMA-API: device driver syncs "
-				"device read-only DMA memory for cpu "
-				"[device address=0x%016llx] [size=%llu bytes] "
-				"[mapped with %s] [synced with %s]\n",
-				(unsigned long long)ref->dev_addr, entry->size,
-				dir2name[entry->direction],
-				dir2name[ref->direction]);
-
-	if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
-		       !(ref->direction == DMA_FROM_DEVICE))
-		err_printk(dev, entry, "DMA-API: device driver syncs "
-				"device write-only DMA memory to device "
-				"[device address=0x%016llx] [size=%llu bytes] "
-				"[mapped with %s] [synced with %s]\n",
-				(unsigned long long)ref->dev_addr, entry->size,
-				dir2name[entry->direction],
-				dir2name[ref->direction]);
-
-	if (ref->sg_call_ents && ref->type == dma_debug_sg &&
-	    ref->sg_call_ents != entry->sg_call_ents) {
-		err_printk(ref->dev, entry, "DMA-API: device driver syncs "
-			   "DMA sg list with different entry count "
-			   "[map count=%d] [sync count=%d]\n",
-			   entry->sg_call_ents, ref->sg_call_ents);
-	}
-
-out:
-	put_hash_bucket(bucket, &flags);
-}
-
-static void check_sg_segment(struct device *dev, struct scatterlist *sg)
-{
-#ifdef CONFIG_DMA_API_DEBUG_SG
-	unsigned int max_seg = dma_get_max_seg_size(dev);
-	u64 start, end, boundary = dma_get_seg_boundary(dev);
-
-	/*
-	 * Either the driver forgot to set dma_parms appropriately, or
-	 * whoever generated the list forgot to check them.
-	 */
-	if (sg->length > max_seg)
-		err_printk(dev, NULL, "DMA-API: mapping sg segment longer than device claims to support [len=%u] [max=%u]\n",
-			   sg->length, max_seg);
-	/*
-	 * In some cases this could potentially be the DMA API
-	 * implementation's fault, but it would usually imply that
-	 * the scatterlist was built inappropriately to begin with.
-	 */
-	start = sg_dma_address(sg);
-	end = start + sg_dma_len(sg) - 1;
-	if ((start ^ end) & ~boundary)
-		err_printk(dev, NULL, "DMA-API: mapping sg segment across boundary [start=0x%016llx] [end=0x%016llx] [boundary=0x%016llx]\n",
-			   start, end, boundary);
-#endif
-}
-
-void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
-			size_t size, int direction, dma_addr_t dma_addr,
-			bool map_single)
-{
-	struct dma_debug_entry *entry;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	if (dma_mapping_error(dev, dma_addr))
-		return;
-
-	entry = dma_entry_alloc();
-	if (!entry)
-		return;
-
-	entry->dev       = dev;
-	entry->type      = dma_debug_page;
-	entry->pfn	 = page_to_pfn(page);
-	entry->offset	 = offset,
-	entry->dev_addr  = dma_addr;
-	entry->size      = size;
-	entry->direction = direction;
-	entry->map_err_type = MAP_ERR_NOT_CHECKED;
-
-	if (map_single)
-		entry->type = dma_debug_single;
-
-	check_for_stack(dev, page, offset);
-
-	if (!PageHighMem(page)) {
-		void *addr = page_address(page) + offset;
-
-		check_for_illegal_area(dev, addr, size);
-	}
-
-	add_dma_entry(entry);
-}
-EXPORT_SYMBOL(debug_dma_map_page);
-
-void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
-{
-	struct dma_debug_entry ref;
-	struct dma_debug_entry *entry;
-	struct hash_bucket *bucket;
-	unsigned long flags;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	ref.dev = dev;
-	ref.dev_addr = dma_addr;
-	bucket = get_hash_bucket(&ref, &flags);
-
-	list_for_each_entry(entry, &bucket->list, list) {
-		if (!exact_match(&ref, entry))
-			continue;
-
-		/*
-		 * The same physical address can be mapped multiple
-		 * times. Without a hardware IOMMU this results in the
-		 * same device addresses being put into the dma-debug
-		 * hash multiple times too. This can result in false
-		 * positives being reported. Therefore we implement a
-		 * best-fit algorithm here which updates the first entry
-		 * from the hash which fits the reference value and is
-		 * not currently listed as being checked.
-		 */
-		if (entry->map_err_type == MAP_ERR_NOT_CHECKED) {
-			entry->map_err_type = MAP_ERR_CHECKED;
-			break;
-		}
-	}
-
-	put_hash_bucket(bucket, &flags);
-}
-EXPORT_SYMBOL(debug_dma_mapping_error);
-
-void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
-			  size_t size, int direction, bool map_single)
-{
-	struct dma_debug_entry ref = {
-		.type           = dma_debug_page,
-		.dev            = dev,
-		.dev_addr       = addr,
-		.size           = size,
-		.direction      = direction,
-	};
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	if (map_single)
-		ref.type = dma_debug_single;
-
-	check_unmap(&ref);
-}
-EXPORT_SYMBOL(debug_dma_unmap_page);
-
-void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
-		      int nents, int mapped_ents, int direction)
-{
-	struct dma_debug_entry *entry;
-	struct scatterlist *s;
-	int i;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	for_each_sg(sg, s, mapped_ents, i) {
-		entry = dma_entry_alloc();
-		if (!entry)
-			return;
-
-		entry->type           = dma_debug_sg;
-		entry->dev            = dev;
-		entry->pfn	      = page_to_pfn(sg_page(s));
-		entry->offset	      = s->offset,
-		entry->size           = sg_dma_len(s);
-		entry->dev_addr       = sg_dma_address(s);
-		entry->direction      = direction;
-		entry->sg_call_ents   = nents;
-		entry->sg_mapped_ents = mapped_ents;
-
-		check_for_stack(dev, sg_page(s), s->offset);
-
-		if (!PageHighMem(sg_page(s))) {
-			check_for_illegal_area(dev, sg_virt(s), sg_dma_len(s));
-		}
-
-		check_sg_segment(dev, s);
-
-		add_dma_entry(entry);
-	}
-}
-EXPORT_SYMBOL(debug_dma_map_sg);
-
-static int get_nr_mapped_entries(struct device *dev,
-				 struct dma_debug_entry *ref)
-{
-	struct dma_debug_entry *entry;
-	struct hash_bucket *bucket;
-	unsigned long flags;
-	int mapped_ents;
-
-	bucket       = get_hash_bucket(ref, &flags);
-	entry        = bucket_find_exact(bucket, ref);
-	mapped_ents  = 0;
-
-	if (entry)
-		mapped_ents = entry->sg_mapped_ents;
-	put_hash_bucket(bucket, &flags);
-
-	return mapped_ents;
-}
-
-void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
-			int nelems, int dir)
-{
-	struct scatterlist *s;
-	int mapped_ents = 0, i;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	for_each_sg(sglist, s, nelems, i) {
-
-		struct dma_debug_entry ref = {
-			.type           = dma_debug_sg,
-			.dev            = dev,
-			.pfn		= page_to_pfn(sg_page(s)),
-			.offset		= s->offset,
-			.dev_addr       = sg_dma_address(s),
-			.size           = sg_dma_len(s),
-			.direction      = dir,
-			.sg_call_ents   = nelems,
-		};
-
-		if (mapped_ents && i >= mapped_ents)
-			break;
-
-		if (!i)
-			mapped_ents = get_nr_mapped_entries(dev, &ref);
-
-		check_unmap(&ref);
-	}
-}
-EXPORT_SYMBOL(debug_dma_unmap_sg);
-
-void debug_dma_alloc_coherent(struct device *dev, size_t size,
-			      dma_addr_t dma_addr, void *virt)
-{
-	struct dma_debug_entry *entry;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	if (unlikely(virt == NULL))
-		return;
-
-	/* handle vmalloc and linear addresses */
-	if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt))
-		return;
-
-	entry = dma_entry_alloc();
-	if (!entry)
-		return;
-
-	entry->type      = dma_debug_coherent;
-	entry->dev       = dev;
-	entry->offset	 = offset_in_page(virt);
-	entry->size      = size;
-	entry->dev_addr  = dma_addr;
-	entry->direction = DMA_BIDIRECTIONAL;
-
-	if (is_vmalloc_addr(virt))
-		entry->pfn = vmalloc_to_pfn(virt);
-	else
-		entry->pfn = page_to_pfn(virt_to_page(virt));
-
-	add_dma_entry(entry);
-}
-EXPORT_SYMBOL(debug_dma_alloc_coherent);
-
-void debug_dma_free_coherent(struct device *dev, size_t size,
-			 void *virt, dma_addr_t addr)
-{
-	struct dma_debug_entry ref = {
-		.type           = dma_debug_coherent,
-		.dev            = dev,
-		.offset		= offset_in_page(virt),
-		.dev_addr       = addr,
-		.size           = size,
-		.direction      = DMA_BIDIRECTIONAL,
-	};
-
-	/* handle vmalloc and linear addresses */
-	if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt))
-		return;
-
-	if (is_vmalloc_addr(virt))
-		ref.pfn = vmalloc_to_pfn(virt);
-	else
-		ref.pfn = page_to_pfn(virt_to_page(virt));
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	check_unmap(&ref);
-}
-EXPORT_SYMBOL(debug_dma_free_coherent);
-
-void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size,
-			    int direction, dma_addr_t dma_addr)
-{
-	struct dma_debug_entry *entry;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	entry = dma_entry_alloc();
-	if (!entry)
-		return;
-
-	entry->type		= dma_debug_resource;
-	entry->dev		= dev;
-	entry->pfn		= PHYS_PFN(addr);
-	entry->offset		= offset_in_page(addr);
-	entry->size		= size;
-	entry->dev_addr		= dma_addr;
-	entry->direction	= direction;
-	entry->map_err_type	= MAP_ERR_NOT_CHECKED;
-
-	add_dma_entry(entry);
-}
-EXPORT_SYMBOL(debug_dma_map_resource);
-
-void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr,
-			      size_t size, int direction)
-{
-	struct dma_debug_entry ref = {
-		.type           = dma_debug_resource,
-		.dev            = dev,
-		.dev_addr       = dma_addr,
-		.size           = size,
-		.direction      = direction,
-	};
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	check_unmap(&ref);
-}
-EXPORT_SYMBOL(debug_dma_unmap_resource);
-
-void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
-				   size_t size, int direction)
-{
-	struct dma_debug_entry ref;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	ref.type         = dma_debug_single;
-	ref.dev          = dev;
-	ref.dev_addr     = dma_handle;
-	ref.size         = size;
-	ref.direction    = direction;
-	ref.sg_call_ents = 0;
-
-	check_sync(dev, &ref, true);
-}
-EXPORT_SYMBOL(debug_dma_sync_single_for_cpu);
-
-void debug_dma_sync_single_for_device(struct device *dev,
-				      dma_addr_t dma_handle, size_t size,
-				      int direction)
-{
-	struct dma_debug_entry ref;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	ref.type         = dma_debug_single;
-	ref.dev          = dev;
-	ref.dev_addr     = dma_handle;
-	ref.size         = size;
-	ref.direction    = direction;
-	ref.sg_call_ents = 0;
-
-	check_sync(dev, &ref, false);
-}
-EXPORT_SYMBOL(debug_dma_sync_single_for_device);
-
-void debug_dma_sync_single_range_for_cpu(struct device *dev,
-					 dma_addr_t dma_handle,
-					 unsigned long offset, size_t size,
-					 int direction)
-{
-	struct dma_debug_entry ref;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	ref.type         = dma_debug_single;
-	ref.dev          = dev;
-	ref.dev_addr     = dma_handle;
-	ref.size         = offset + size;
-	ref.direction    = direction;
-	ref.sg_call_ents = 0;
-
-	check_sync(dev, &ref, true);
-}
-EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu);
-
-void debug_dma_sync_single_range_for_device(struct device *dev,
-					    dma_addr_t dma_handle,
-					    unsigned long offset,
-					    size_t size, int direction)
-{
-	struct dma_debug_entry ref;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	ref.type         = dma_debug_single;
-	ref.dev          = dev;
-	ref.dev_addr     = dma_handle;
-	ref.size         = offset + size;
-	ref.direction    = direction;
-	ref.sg_call_ents = 0;
-
-	check_sync(dev, &ref, false);
-}
-EXPORT_SYMBOL(debug_dma_sync_single_range_for_device);
-
-void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
-			       int nelems, int direction)
-{
-	struct scatterlist *s;
-	int mapped_ents = 0, i;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	for_each_sg(sg, s, nelems, i) {
-
-		struct dma_debug_entry ref = {
-			.type           = dma_debug_sg,
-			.dev            = dev,
-			.pfn		= page_to_pfn(sg_page(s)),
-			.offset		= s->offset,
-			.dev_addr       = sg_dma_address(s),
-			.size           = sg_dma_len(s),
-			.direction      = direction,
-			.sg_call_ents   = nelems,
-		};
-
-		if (!i)
-			mapped_ents = get_nr_mapped_entries(dev, &ref);
-
-		if (i >= mapped_ents)
-			break;
-
-		check_sync(dev, &ref, true);
-	}
-}
-EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu);
-
-void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
-				  int nelems, int direction)
-{
-	struct scatterlist *s;
-	int mapped_ents = 0, i;
-
-	if (unlikely(dma_debug_disabled()))
-		return;
-
-	for_each_sg(sg, s, nelems, i) {
-
-		struct dma_debug_entry ref = {
-			.type           = dma_debug_sg,
-			.dev            = dev,
-			.pfn		= page_to_pfn(sg_page(s)),
-			.offset		= s->offset,
-			.dev_addr       = sg_dma_address(s),
-			.size           = sg_dma_len(s),
-			.direction      = direction,
-			.sg_call_ents   = nelems,
-		};
-		if (!i)
-			mapped_ents = get_nr_mapped_entries(dev, &ref);
-
-		if (i >= mapped_ents)
-			break;
-
-		check_sync(dev, &ref, false);
-	}
-}
-EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
-
-static int __init dma_debug_driver_setup(char *str)
-{
-	int i;
-
-	for (i = 0; i < NAME_MAX_LEN - 1; ++i, ++str) {
-		current_driver_name[i] = *str;
-		if (*str == 0)
-			break;
-	}
-
-	if (current_driver_name[0])
-		pr_info("DMA-API: enable driver filter for driver [%s]\n",
-			current_driver_name);
-
-
-	return 1;
-}
-__setup("dma_debug_driver=", dma_debug_driver_setup);
diff --git a/lib/dma-direct.c b/lib/dma-direct.c
deleted file mode 100644
index 8be8106..0000000
--- a/lib/dma-direct.c
+++ /dev/null
@@ -1,204 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * DMA operations that map physical memory directly without using an IOMMU or
- * flushing caches.
- */
-#include <linux/export.h>
-#include <linux/mm.h>
-#include <linux/dma-direct.h>
-#include <linux/scatterlist.h>
-#include <linux/dma-contiguous.h>
-#include <linux/pfn.h>
-#include <linux/set_memory.h>
-
-#define DIRECT_MAPPING_ERROR		0
-
-/*
- * Most architectures use ZONE_DMA for the first 16 Megabytes, but
- * some use it for entirely different regions:
- */
-#ifndef ARCH_ZONE_DMA_BITS
-#define ARCH_ZONE_DMA_BITS 24
-#endif
-
-/*
- * For AMD SEV all DMA must be to unencrypted addresses.
- */
-static inline bool force_dma_unencrypted(void)
-{
-	return sev_active();
-}
-
-static bool
-check_addr(struct device *dev, dma_addr_t dma_addr, size_t size,
-		const char *caller)
-{
-	if (unlikely(dev && !dma_capable(dev, dma_addr, size))) {
-		if (!dev->dma_mask) {
-			dev_err(dev,
-				"%s: call on device without dma_mask\n",
-				caller);
-			return false;
-		}
-
-		if (*dev->dma_mask >= DMA_BIT_MASK(32)) {
-			dev_err(dev,
-				"%s: overflow %pad+%zu of device mask %llx\n",
-				caller, &dma_addr, size, *dev->dma_mask);
-		}
-		return false;
-	}
-	return true;
-}
-
-static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
-{
-	dma_addr_t addr = force_dma_unencrypted() ?
-		__phys_to_dma(dev, phys) : phys_to_dma(dev, phys);
-	return addr + size - 1 <= dev->coherent_dma_mask;
-}
-
-void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
-		gfp_t gfp, unsigned long attrs)
-{
-	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
-	int page_order = get_order(size);
-	struct page *page = NULL;
-	void *ret;
-
-	/* we always manually zero the memory once we are done: */
-	gfp &= ~__GFP_ZERO;
-
-	/* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */
-	if (dev->coherent_dma_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
-		gfp |= GFP_DMA;
-	if (dev->coherent_dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
-		gfp |= GFP_DMA32;
-
-again:
-	/* CMA can be used only in the context which permits sleeping */
-	if (gfpflags_allow_blocking(gfp)) {
-		page = dma_alloc_from_contiguous(dev, count, page_order, gfp);
-		if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
-			dma_release_from_contiguous(dev, page, count);
-			page = NULL;
-		}
-	}
-	if (!page)
-		page = alloc_pages_node(dev_to_node(dev), gfp, page_order);
-
-	if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
-		__free_pages(page, page_order);
-		page = NULL;
-
-		if (IS_ENABLED(CONFIG_ZONE_DMA32) &&
-		    dev->coherent_dma_mask < DMA_BIT_MASK(64) &&
-		    !(gfp & (GFP_DMA32 | GFP_DMA))) {
-			gfp |= GFP_DMA32;
-			goto again;
-		}
-
-		if (IS_ENABLED(CONFIG_ZONE_DMA) &&
-		    dev->coherent_dma_mask < DMA_BIT_MASK(32) &&
-		    !(gfp & GFP_DMA)) {
-			gfp = (gfp & ~GFP_DMA32) | GFP_DMA;
-			goto again;
-		}
-	}
-
-	if (!page)
-		return NULL;
-	ret = page_address(page);
-	if (force_dma_unencrypted()) {
-		set_memory_decrypted((unsigned long)ret, 1 << page_order);
-		*dma_handle = __phys_to_dma(dev, page_to_phys(page));
-	} else {
-		*dma_handle = phys_to_dma(dev, page_to_phys(page));
-	}
-	memset(ret, 0, size);
-	return ret;
-}
-
-/*
- * NOTE: this function must never look at the dma_addr argument, because we want
- * to be able to use it as a helper for iommu implementations as well.
- */
-void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
-		dma_addr_t dma_addr, unsigned long attrs)
-{
-	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
-	unsigned int page_order = get_order(size);
-
-	if (force_dma_unencrypted())
-		set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order);
-	if (!dma_release_from_contiguous(dev, virt_to_page(cpu_addr), count))
-		free_pages((unsigned long)cpu_addr, page_order);
-}
-
-dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
-		unsigned long offset, size_t size, enum dma_data_direction dir,
-		unsigned long attrs)
-{
-	dma_addr_t dma_addr = phys_to_dma(dev, page_to_phys(page)) + offset;
-
-	if (!check_addr(dev, dma_addr, size, __func__))
-		return DIRECT_MAPPING_ERROR;
-	return dma_addr;
-}
-
-int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
-		enum dma_data_direction dir, unsigned long attrs)
-{
-	int i;
-	struct scatterlist *sg;
-
-	for_each_sg(sgl, sg, nents, i) {
-		BUG_ON(!sg_page(sg));
-
-		sg_dma_address(sg) = phys_to_dma(dev, sg_phys(sg));
-		if (!check_addr(dev, sg_dma_address(sg), sg->length, __func__))
-			return 0;
-		sg_dma_len(sg) = sg->length;
-	}
-
-	return nents;
-}
-
-int dma_direct_supported(struct device *dev, u64 mask)
-{
-#ifdef CONFIG_ZONE_DMA
-	if (mask < DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
-		return 0;
-#else
-	/*
-	 * Because 32-bit DMA masks are so common we expect every architecture
-	 * to be able to satisfy them - either by not supporting more physical
-	 * memory, or by providing a ZONE_DMA32.  If neither is the case, the
-	 * architecture needs to use an IOMMU instead of the direct mapping.
-	 */
-	if (mask < DMA_BIT_MASK(32))
-		return 0;
-#endif
-	/*
-	 * Various PCI/PCIe bridges have broken support for > 32bit DMA even
-	 * if the device itself might support it.
-	 */
-	if (dev->dma_32bit_limit && mask > DMA_BIT_MASK(32))
-		return 0;
-	return 1;
-}
-
-int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr)
-{
-	return dma_addr == DIRECT_MAPPING_ERROR;
-}
-
-const struct dma_map_ops dma_direct_ops = {
-	.alloc			= dma_direct_alloc,
-	.free			= dma_direct_free,
-	.map_page		= dma_direct_map_page,
-	.map_sg			= dma_direct_map_sg,
-	.dma_supported		= dma_direct_supported,
-	.mapping_error		= dma_direct_mapping_error,
-};
-EXPORT_SYMBOL(dma_direct_ops);
diff --git a/lib/dma-noncoherent.c b/lib/dma-noncoherent.c
deleted file mode 100644
index 79e9a75..0000000
--- a/lib/dma-noncoherent.c
+++ /dev/null
@@ -1,102 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2018 Christoph Hellwig.
- *
- * DMA operations that map physical memory directly without providing cache
- * coherence.
- */
-#include <linux/export.h>
-#include <linux/mm.h>
-#include <linux/dma-direct.h>
-#include <linux/dma-noncoherent.h>
-#include <linux/scatterlist.h>
-
-static void dma_noncoherent_sync_single_for_device(struct device *dev,
-		dma_addr_t addr, size_t size, enum dma_data_direction dir)
-{
-	arch_sync_dma_for_device(dev, dma_to_phys(dev, addr), size, dir);
-}
-
-static void dma_noncoherent_sync_sg_for_device(struct device *dev,
-		struct scatterlist *sgl, int nents, enum dma_data_direction dir)
-{
-	struct scatterlist *sg;
-	int i;
-
-	for_each_sg(sgl, sg, nents, i)
-		arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir);
-}
-
-static dma_addr_t dma_noncoherent_map_page(struct device *dev, struct page *page,
-		unsigned long offset, size_t size, enum dma_data_direction dir,
-		unsigned long attrs)
-{
-	dma_addr_t addr;
-
-	addr = dma_direct_map_page(dev, page, offset, size, dir, attrs);
-	if (!dma_mapping_error(dev, addr) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		arch_sync_dma_for_device(dev, page_to_phys(page) + offset,
-				size, dir);
-	return addr;
-}
-
-static int dma_noncoherent_map_sg(struct device *dev, struct scatterlist *sgl,
-		int nents, enum dma_data_direction dir, unsigned long attrs)
-{
-	nents = dma_direct_map_sg(dev, sgl, nents, dir, attrs);
-	if (nents > 0 && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		dma_noncoherent_sync_sg_for_device(dev, sgl, nents, dir);
-	return nents;
-}
-
-#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU
-static void dma_noncoherent_sync_single_for_cpu(struct device *dev,
-		dma_addr_t addr, size_t size, enum dma_data_direction dir)
-{
-	arch_sync_dma_for_cpu(dev, dma_to_phys(dev, addr), size, dir);
-}
-
-static void dma_noncoherent_sync_sg_for_cpu(struct device *dev,
-		struct scatterlist *sgl, int nents, enum dma_data_direction dir)
-{
-	struct scatterlist *sg;
-	int i;
-
-	for_each_sg(sgl, sg, nents, i)
-		arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir);
-}
-
-static void dma_noncoherent_unmap_page(struct device *dev, dma_addr_t addr,
-		size_t size, enum dma_data_direction dir, unsigned long attrs)
-{
-	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		dma_noncoherent_sync_single_for_cpu(dev, addr, size, dir);
-}
-
-static void dma_noncoherent_unmap_sg(struct device *dev, struct scatterlist *sgl,
-		int nents, enum dma_data_direction dir, unsigned long attrs)
-{
-	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
-		dma_noncoherent_sync_sg_for_cpu(dev, sgl, nents, dir);
-}
-#endif
-
-const struct dma_map_ops dma_noncoherent_ops = {
-	.alloc			= arch_dma_alloc,
-	.free			= arch_dma_free,
-	.mmap			= arch_dma_mmap,
-	.sync_single_for_device	= dma_noncoherent_sync_single_for_device,
-	.sync_sg_for_device	= dma_noncoherent_sync_sg_for_device,
-	.map_page		= dma_noncoherent_map_page,
-	.map_sg			= dma_noncoherent_map_sg,
-#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU
-	.sync_single_for_cpu	= dma_noncoherent_sync_single_for_cpu,
-	.sync_sg_for_cpu	= dma_noncoherent_sync_sg_for_cpu,
-	.unmap_page		= dma_noncoherent_unmap_page,
-	.unmap_sg		= dma_noncoherent_unmap_sg,
-#endif
-	.dma_supported		= dma_direct_supported,
-	.mapping_error		= dma_direct_mapping_error,
-	.cache_sync		= arch_dma_cache_sync,
-};
-EXPORT_SYMBOL(dma_noncoherent_ops);
diff --git a/lib/dma-virt.c b/lib/dma-virt.c
deleted file mode 100644
index 8e61a02..0000000
--- a/lib/dma-virt.c
+++ /dev/null
@@ -1,61 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- *	lib/dma-virt.c
- *
- * DMA operations that map to virtual addresses without flushing memory.
- */
-#include <linux/export.h>
-#include <linux/mm.h>
-#include <linux/dma-mapping.h>
-#include <linux/scatterlist.h>
-
-static void *dma_virt_alloc(struct device *dev, size_t size,
-			    dma_addr_t *dma_handle, gfp_t gfp,
-			    unsigned long attrs)
-{
-	void *ret;
-
-	ret = (void *)__get_free_pages(gfp, get_order(size));
-	if (ret)
-		*dma_handle = (uintptr_t)ret;
-	return ret;
-}
-
-static void dma_virt_free(struct device *dev, size_t size,
-			  void *cpu_addr, dma_addr_t dma_addr,
-			  unsigned long attrs)
-{
-	free_pages((unsigned long)cpu_addr, get_order(size));
-}
-
-static dma_addr_t dma_virt_map_page(struct device *dev, struct page *page,
-				    unsigned long offset, size_t size,
-				    enum dma_data_direction dir,
-				    unsigned long attrs)
-{
-	return (uintptr_t)(page_address(page) + offset);
-}
-
-static int dma_virt_map_sg(struct device *dev, struct scatterlist *sgl,
-			   int nents, enum dma_data_direction dir,
-			   unsigned long attrs)
-{
-	int i;
-	struct scatterlist *sg;
-
-	for_each_sg(sgl, sg, nents, i) {
-		BUG_ON(!sg_page(sg));
-		sg_dma_address(sg) = (uintptr_t)sg_virt(sg);
-		sg_dma_len(sg) = sg->length;
-	}
-
-	return nents;
-}
-
-const struct dma_map_ops dma_virt_ops = {
-	.alloc			= dma_virt_alloc,
-	.free			= dma_virt_free,
-	.map_page		= dma_virt_map_page,
-	.map_sg			= dma_virt_map_sg,
-};
-EXPORT_SYMBOL(dma_virt_ops);
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
deleted file mode 100644
index 04b68d9..0000000
--- a/lib/swiotlb.c
+++ /dev/null
@@ -1,1087 +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@intel.com>
- * Copyright (C) 2000 Goutham Rao <goutham.rao@intel.com>
- * Copyright (C) 2000, 2003 Hewlett-Packard Co
- *	David Mosberger-Tang <davidm@hpl.hp.com>
- *
- * 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-direct.h>
-#include <linux/mm.h>
-#include <linux/export.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/gfp.h>
-#include <linux/scatterlist.h>
-#include <linux/mem_encrypt.h>
-#include <linux/set_memory.h>
-
-#include <asm/io.h>
-#include <asm/dma.h>
-
-#include <linux/init.h>
-#include <linux/bootmem.h>
-#include <linux/iommu-helper.h>
-
-#define CREATE_TRACE_POINTS
-#include <trace/events/swiotlb.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)
-
-enum swiotlb_force swiotlb_force;
-
-/*
- * Used to do a quick range check in swiotlb_tbl_unmap_single and
- * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this
- * API.
- */
-static phys_addr_t io_tlb_start, io_tlb_end;
-
-/*
- * The number of IO TLB blocks (in groups of 64) between io_tlb_start and
- * io_tlb_end.  This is command line adjustable via setup_io_tlb_npages.
- */
-static unsigned long io_tlb_nslabs;
-
-/*
- * When the IOMMU overflows we return a fallback buffer. This sets the size.
- */
-static unsigned long io_tlb_overflow = 32*1024;
-
-static phys_addr_t 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;
-
-/*
- * Max segment that we can provide which (if pages are contingous) will
- * not be bounced (unless SWIOTLB_FORCE is set).
- */
-unsigned int max_segment;
-
-/*
- * We need to save away the original address corresponding to a mapped entry
- * for the sync operations.
- */
-#define INVALID_PHYS_ADDR (~(phys_addr_t)0)
-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)
-{
-	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 (*str == ',')
-		++str;
-	if (!strcmp(str, "force")) {
-		swiotlb_force = SWIOTLB_FORCE;
-	} else if (!strcmp(str, "noforce")) {
-		swiotlb_force = SWIOTLB_NO_FORCE;
-		io_tlb_nslabs = 1;
-	}
-
-	return 0;
-}
-early_param("swiotlb", setup_io_tlb_npages);
-/* make io_tlb_overflow tunable too? */
-
-unsigned long swiotlb_nr_tbl(void)
-{
-	return io_tlb_nslabs;
-}
-EXPORT_SYMBOL_GPL(swiotlb_nr_tbl);
-
-unsigned int swiotlb_max_segment(void)
-{
-	return max_segment;
-}
-EXPORT_SYMBOL_GPL(swiotlb_max_segment);
-
-void swiotlb_set_max_segment(unsigned int val)
-{
-	if (swiotlb_force == SWIOTLB_FORCE)
-		max_segment = 1;
-	else
-		max_segment = rounddown(val, PAGE_SIZE);
-}
-
-/* default to 64MB */
-#define IO_TLB_DEFAULT_SIZE (64UL<<20)
-unsigned long swiotlb_size_or_default(void)
-{
-	unsigned long size;
-
-	size = io_tlb_nslabs << IO_TLB_SHIFT;
-
-	return size ? size : (IO_TLB_DEFAULT_SIZE);
-}
-
-static bool no_iotlb_memory;
-
-void swiotlb_print_info(void)
-{
-	unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT;
-	unsigned char *vstart, *vend;
-
-	if (no_iotlb_memory) {
-		pr_warn("software IO TLB: No low mem\n");
-		return;
-	}
-
-	vstart = phys_to_virt(io_tlb_start);
-	vend = phys_to_virt(io_tlb_end);
-
-	printk(KERN_INFO "software IO TLB [mem %#010llx-%#010llx] (%luMB) mapped at [%p-%p]\n",
-	       (unsigned long long)io_tlb_start,
-	       (unsigned long long)io_tlb_end,
-	       bytes >> 20, vstart, vend - 1);
-}
-
-/*
- * Early SWIOTLB allocation may be too early to allow an architecture to
- * perform the desired operations.  This function allows the architecture to
- * call SWIOTLB when the operations are possible.  It needs to be called
- * before the SWIOTLB memory is used.
- */
-void __init swiotlb_update_mem_attributes(void)
-{
-	void *vaddr;
-	unsigned long bytes;
-
-	if (no_iotlb_memory || late_alloc)
-		return;
-
-	vaddr = phys_to_virt(io_tlb_start);
-	bytes = PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT);
-	set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT);
-	memset(vaddr, 0, bytes);
-
-	vaddr = phys_to_virt(io_tlb_overflow_buffer);
-	bytes = PAGE_ALIGN(io_tlb_overflow);
-	set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT);
-	memset(vaddr, 0, bytes);
-}
-
-int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
-{
-	void *v_overflow_buffer;
-	unsigned long i, bytes;
-
-	bytes = nslabs << IO_TLB_SHIFT;
-
-	io_tlb_nslabs = nslabs;
-	io_tlb_start = __pa(tlb);
-	io_tlb_end = io_tlb_start + bytes;
-
-	/*
-	 * Get the overflow emergency buffer
-	 */
-	v_overflow_buffer = memblock_virt_alloc_low_nopanic(
-						PAGE_ALIGN(io_tlb_overflow),
-						PAGE_SIZE);
-	if (!v_overflow_buffer)
-		return -ENOMEM;
-
-	io_tlb_overflow_buffer = __pa(v_overflow_buffer);
-
-	/*
-	 * 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 = memblock_virt_alloc(
-				PAGE_ALIGN(io_tlb_nslabs * sizeof(int)),
-				PAGE_SIZE);
-	io_tlb_orig_addr = memblock_virt_alloc(
-				PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)),
-				PAGE_SIZE);
-	for (i = 0; i < io_tlb_nslabs; i++) {
-		io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
-		io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
-	}
-	io_tlb_index = 0;
-
-	if (verbose)
-		swiotlb_print_info();
-
-	swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT);
-	return 0;
-}
-
-/*
- * 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(int verbose)
-{
-	size_t default_size = IO_TLB_DEFAULT_SIZE;
-	unsigned char *vstart;
-	unsigned long 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 */
-	vstart = memblock_virt_alloc_low_nopanic(PAGE_ALIGN(bytes), PAGE_SIZE);
-	if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose))
-		return;
-
-	if (io_tlb_start)
-		memblock_free_early(io_tlb_start,
-				    PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
-	pr_warn("Cannot allocate SWIOTLB buffer");
-	no_iotlb_memory = true;
-}
-
-/*
- * 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_late_init_with_default_size(size_t default_size)
-{
-	unsigned long bytes, req_nslabs = io_tlb_nslabs;
-	unsigned char *vstart = NULL;
-	unsigned int order;
-	int rc = 0;
-
-	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) {
-		vstart = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
-						  order);
-		if (vstart)
-			break;
-		order--;
-	}
-
-	if (!vstart) {
-		io_tlb_nslabs = req_nslabs;
-		return -ENOMEM;
-	}
-	if (order != get_order(bytes)) {
-		printk(KERN_WARNING "Warning: only able to allocate %ld MB "
-		       "for software IO TLB\n", (PAGE_SIZE << order) >> 20);
-		io_tlb_nslabs = SLABS_PER_PAGE << order;
-	}
-	rc = swiotlb_late_init_with_tbl(vstart, io_tlb_nslabs);
-	if (rc)
-		free_pages((unsigned long)vstart, order);
-
-	return rc;
-}
-
-int
-swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
-{
-	unsigned long i, bytes;
-	unsigned char *v_overflow_buffer;
-
-	bytes = nslabs << IO_TLB_SHIFT;
-
-	io_tlb_nslabs = nslabs;
-	io_tlb_start = virt_to_phys(tlb);
-	io_tlb_end = io_tlb_start + bytes;
-
-	set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT);
-	memset(tlb, 0, bytes);
-
-	/*
-	 * Get the overflow emergency buffer
-	 */
-	v_overflow_buffer = (void *)__get_free_pages(GFP_DMA,
-						     get_order(io_tlb_overflow));
-	if (!v_overflow_buffer)
-		goto cleanup2;
-
-	set_memory_decrypted((unsigned long)v_overflow_buffer,
-			io_tlb_overflow >> PAGE_SHIFT);
-	memset(v_overflow_buffer, 0, io_tlb_overflow);
-	io_tlb_overflow_buffer = virt_to_phys(v_overflow_buffer);
-
-	/*
-	 * 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 cleanup3;
-
-	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 cleanup4;
-
-	for (i = 0; i < io_tlb_nslabs; i++) {
-		io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
-		io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
-	}
-	io_tlb_index = 0;
-
-	swiotlb_print_info();
-
-	late_alloc = 1;
-
-	swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT);
-
-	return 0;
-
-cleanup4:
-	free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
-	                                                 sizeof(int)));
-	io_tlb_list = NULL;
-cleanup3:
-	free_pages((unsigned long)v_overflow_buffer,
-		   get_order(io_tlb_overflow));
-	io_tlb_overflow_buffer = 0;
-cleanup2:
-	io_tlb_end = 0;
-	io_tlb_start = 0;
-	io_tlb_nslabs = 0;
-	max_segment = 0;
-	return -ENOMEM;
-}
-
-void __init swiotlb_exit(void)
-{
-	if (!io_tlb_orig_addr)
-		return;
-
-	if (late_alloc) {
-		free_pages((unsigned long)phys_to_virt(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)phys_to_virt(io_tlb_start),
-			   get_order(io_tlb_nslabs << IO_TLB_SHIFT));
-	} else {
-		memblock_free_late(io_tlb_overflow_buffer,
-				   PAGE_ALIGN(io_tlb_overflow));
-		memblock_free_late(__pa(io_tlb_orig_addr),
-				   PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)));
-		memblock_free_late(__pa(io_tlb_list),
-				   PAGE_ALIGN(io_tlb_nslabs * sizeof(int)));
-		memblock_free_late(io_tlb_start,
-				   PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
-	}
-	io_tlb_nslabs = 0;
-	max_segment = 0;
-}
-
-int is_swiotlb_buffer(phys_addr_t paddr)
-{
-	return paddr >= io_tlb_start && paddr < io_tlb_end;
-}
-
-/*
- * Bounce: copy the swiotlb buffer back to the original dma location
- */
-static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr,
-			   size_t size, enum dma_data_direction dir)
-{
-	unsigned long pfn = PFN_DOWN(orig_addr);
-	unsigned char *vaddr = phys_to_virt(tlb_addr);
-
-	if (PageHighMem(pfn_to_page(pfn))) {
-		/* The buffer does not have a mapping.  Map it in and copy */
-		unsigned int offset = orig_addr & ~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));
-			if (dir == DMA_TO_DEVICE)
-				memcpy(vaddr, buffer + offset, sz);
-			else
-				memcpy(buffer + offset, vaddr, sz);
-			kunmap_atomic(buffer);
-			local_irq_restore(flags);
-
-			size -= sz;
-			pfn++;
-			vaddr += sz;
-			offset = 0;
-		}
-	} else if (dir == DMA_TO_DEVICE) {
-		memcpy(vaddr, phys_to_virt(orig_addr), size);
-	} else {
-		memcpy(phys_to_virt(orig_addr), vaddr, size);
-	}
-}
-
-phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
-				   dma_addr_t tbl_dma_addr,
-				   phys_addr_t orig_addr, size_t size,
-				   enum dma_data_direction dir,
-				   unsigned long attrs)
-{
-	unsigned long flags;
-	phys_addr_t tlb_addr;
-	unsigned int nslots, stride, index, wrap;
-	int i;
-	unsigned long mask;
-	unsigned long offset_slots;
-	unsigned long max_slots;
-
-	if (no_iotlb_memory)
-		panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer");
-
-	if (mem_encrypt_active())
-		pr_warn_once("%s is active and system is using DMA bounce buffers\n",
-			     sme_active() ? "SME" : "SEV");
-
-	mask = dma_get_seg_boundary(hwdev);
-
-	tbl_dma_addr &= mask;
-
-	offset_slots = ALIGN(tbl_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 or equal to 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;
-			tlb_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);
-	if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit())
-		dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size);
-	return SWIOTLB_MAP_ERROR;
-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] = orig_addr + (i << IO_TLB_SHIFT);
-	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
-	    (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
-		swiotlb_bounce(orig_addr, tlb_addr, size, DMA_TO_DEVICE);
-
-	return tlb_addr;
-}
-
-/*
- * Allocates bounce buffer and returns its physical address.
- */
-static phys_addr_t
-map_single(struct device *hwdev, phys_addr_t phys, size_t size,
-	   enum dma_data_direction dir, unsigned long attrs)
-{
-	dma_addr_t start_dma_addr;
-
-	if (swiotlb_force == SWIOTLB_NO_FORCE) {
-		dev_warn_ratelimited(hwdev, "Cannot do DMA to address %pa\n",
-				     &phys);
-		return SWIOTLB_MAP_ERROR;
-	}
-
-	start_dma_addr = __phys_to_dma(hwdev, io_tlb_start);
-	return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size,
-				      dir, attrs);
-}
-
-/*
- * tlb_addr is the physical address of the bounce buffer to unmap.
- */
-void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
-			      size_t size, enum dma_data_direction dir,
-			      unsigned long attrs)
-{
-	unsigned long flags;
-	int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
-	int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
-	phys_addr_t orig_addr = io_tlb_orig_addr[index];
-
-	/*
-	 * First, sync the memory before unmapping the entry
-	 */
-	if (orig_addr != INVALID_PHYS_ADDR &&
-	    !(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
-	    ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)))
-		swiotlb_bounce(orig_addr, tlb_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;
-			io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
-		}
-		/*
-		 * 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 swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr,
-			     size_t size, enum dma_data_direction dir,
-			     enum dma_sync_target target)
-{
-	int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
-	phys_addr_t orig_addr = io_tlb_orig_addr[index];
-
-	if (orig_addr == INVALID_PHYS_ADDR)
-		return;
-	orig_addr += (unsigned long)tlb_addr & ((1 << IO_TLB_SHIFT) - 1);
-
-	switch (target) {
-	case SYNC_FOR_CPU:
-		if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
-			swiotlb_bounce(orig_addr, tlb_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(orig_addr, tlb_addr,
-				       size, DMA_TO_DEVICE);
-		else
-			BUG_ON(dir != DMA_FROM_DEVICE);
-		break;
-	default:
-		BUG();
-	}
-}
-
-static inline bool dma_coherent_ok(struct device *dev, dma_addr_t addr,
-		size_t size)
-{
-	u64 mask = DMA_BIT_MASK(32);
-
-	if (dev && dev->coherent_dma_mask)
-		mask = dev->coherent_dma_mask;
-	return addr + size - 1 <= mask;
-}
-
-static void *
-swiotlb_alloc_buffer(struct device *dev, size_t size, dma_addr_t *dma_handle,
-		unsigned long attrs)
-{
-	phys_addr_t phys_addr;
-
-	if (swiotlb_force == SWIOTLB_NO_FORCE)
-		goto out_warn;
-
-	phys_addr = swiotlb_tbl_map_single(dev,
-			__phys_to_dma(dev, io_tlb_start),
-			0, size, DMA_FROM_DEVICE, attrs);
-	if (phys_addr == SWIOTLB_MAP_ERROR)
-		goto out_warn;
-
-	*dma_handle = __phys_to_dma(dev, phys_addr);
-	if (!dma_coherent_ok(dev, *dma_handle, size))
-		goto out_unmap;
-
-	memset(phys_to_virt(phys_addr), 0, size);
-	return phys_to_virt(phys_addr);
-
-out_unmap:
-	dev_warn(dev, "hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n",
-		(unsigned long long)dev->coherent_dma_mask,
-		(unsigned long long)*dma_handle);
-
-	/*
-	 * DMA_TO_DEVICE to avoid memcpy in unmap_single.
-	 * DMA_ATTR_SKIP_CPU_SYNC is optional.
-	 */
-	swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE,
-			DMA_ATTR_SKIP_CPU_SYNC);
-out_warn:
-	if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) {
-		dev_warn(dev,
-			"swiotlb: coherent allocation failed, size=%zu\n",
-			size);
-		dump_stack();
-	}
-	return NULL;
-}
-
-static bool swiotlb_free_buffer(struct device *dev, size_t size,
-		dma_addr_t dma_addr)
-{
-	phys_addr_t phys_addr = dma_to_phys(dev, dma_addr);
-
-	WARN_ON_ONCE(irqs_disabled());
-
-	if (!is_swiotlb_buffer(phys_addr))
-		return false;
-
-	/*
-	 * DMA_TO_DEVICE to avoid memcpy in swiotlb_tbl_unmap_single.
-	 * DMA_ATTR_SKIP_CPU_SYNC is optional.
-	 */
-	swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE,
-				 DMA_ATTR_SKIP_CPU_SYNC);
-	return true;
-}
-
-static void
-swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir,
-	     int do_panic)
-{
-	if (swiotlb_force == SWIOTLB_NO_FORCE)
-		return;
-
-	/*
-	 * 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_ratelimited(dev, "DMA: Out of SW-IOMMU space for %zu bytes\n",
-			    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,
-			    unsigned long attrs)
-{
-	phys_addr_t map, phys = page_to_phys(page) + offset;
-	dma_addr_t dev_addr = phys_to_dma(dev, phys);
-
-	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 != SWIOTLB_FORCE)
-		return dev_addr;
-
-	trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force);
-
-	/* Oh well, have to allocate and map a bounce buffer. */
-	map = map_single(dev, phys, size, dir, attrs);
-	if (map == SWIOTLB_MAP_ERROR) {
-		swiotlb_full(dev, size, dir, 1);
-		return __phys_to_dma(dev, io_tlb_overflow_buffer);
-	}
-
-	dev_addr = __phys_to_dma(dev, map);
-
-	/* Ensure that the address returned is DMA'ble */
-	if (dma_capable(dev, dev_addr, size))
-		return dev_addr;
-
-	attrs |= DMA_ATTR_SKIP_CPU_SYNC;
-	swiotlb_tbl_unmap_single(dev, map, size, dir, attrs);
-
-	return __phys_to_dma(dev, io_tlb_overflow_buffer);
-}
-
-/*
- * 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, enum dma_data_direction dir,
-			 unsigned long attrs)
-{
-	phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
-
-	BUG_ON(dir == DMA_NONE);
-
-	if (is_swiotlb_buffer(paddr)) {
-		swiotlb_tbl_unmap_single(hwdev, paddr, size, dir, attrs);
-		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,
-			unsigned long attrs)
-{
-	unmap_single(hwdev, dev_addr, size, dir, attrs);
-}
-
-/*
- * 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, enum dma_data_direction dir,
-		    enum dma_sync_target target)
-{
-	phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
-
-	BUG_ON(dir == DMA_NONE);
-
-	if (is_swiotlb_buffer(paddr)) {
-		swiotlb_tbl_sync_single(hwdev, 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);
-}
-
-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);
-}
-
-/*
- * 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, unsigned long attrs)
-{
-	struct scatterlist *sg;
-	int i;
-
-	BUG_ON(dir == DMA_NONE);
-
-	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 == SWIOTLB_FORCE ||
-		    !dma_capable(hwdev, dev_addr, sg->length)) {
-			phys_addr_t map = map_single(hwdev, sg_phys(sg),
-						     sg->length, dir, attrs);
-			if (map == SWIOTLB_MAP_ERROR) {
-				/* Don't panic here, we expect map_sg users
-				   to do proper error handling. */
-				swiotlb_full(hwdev, sg->length, dir, 0);
-				attrs |= DMA_ATTR_SKIP_CPU_SYNC;
-				swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
-						       attrs);
-				sg_dma_len(sgl) = 0;
-				return 0;
-			}
-			sg->dma_address = __phys_to_dma(hwdev, map);
-		} else
-			sg->dma_address = dev_addr;
-		sg_dma_len(sg) = sg->length;
-	}
-	return nelems;
-}
-
-/*
- * 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,
-		       unsigned long 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_len(sg), dir,
-			     attrs);
-}
-
-/*
- * 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, enum dma_data_direction dir,
-		enum dma_sync_target target)
-{
-	struct scatterlist *sg;
-	int i;
-
-	for_each_sg(sgl, sg, nelems, i)
-		swiotlb_sync_single(hwdev, sg->dma_address,
-				    sg_dma_len(sg), 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);
-}
-
-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);
-}
-
-int
-swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
-{
-	return (dma_addr == __phys_to_dma(hwdev, io_tlb_overflow_buffer));
-}
-
-/*
- * 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 __phys_to_dma(hwdev, io_tlb_end - 1) <= mask;
-}
-
-void *swiotlb_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
-		gfp_t gfp, unsigned long attrs)
-{
-	void *vaddr;
-
-	/* temporary workaround: */
-	if (gfp & __GFP_NOWARN)
-		attrs |= DMA_ATTR_NO_WARN;
-
-	/*
-	 * Don't print a warning when the first allocation attempt fails.
-	 * swiotlb_alloc_coherent() will print a warning when the DMA memory
-	 * allocation ultimately failed.
-	 */
-	gfp |= __GFP_NOWARN;
-
-	vaddr = dma_direct_alloc(dev, size, dma_handle, gfp, attrs);
-	if (!vaddr)
-		vaddr = swiotlb_alloc_buffer(dev, size, dma_handle, attrs);
-	return vaddr;
-}
-
-void swiotlb_free(struct device *dev, size_t size, void *vaddr,
-		dma_addr_t dma_addr, unsigned long attrs)
-{
-	if (!swiotlb_free_buffer(dev, size, dma_addr))
-		dma_direct_free(dev, size, vaddr, dma_addr, attrs);
-}
-
-const struct dma_map_ops swiotlb_dma_ops = {
-	.mapping_error		= swiotlb_dma_mapping_error,
-	.alloc			= swiotlb_alloc,
-	.free			= swiotlb_free,
-	.sync_single_for_cpu	= swiotlb_sync_single_for_cpu,
-	.sync_single_for_device	= swiotlb_sync_single_for_device,
-	.sync_sg_for_cpu	= swiotlb_sync_sg_for_cpu,
-	.sync_sg_for_device	= swiotlb_sync_sg_for_device,
-	.map_sg			= swiotlb_map_sg_attrs,
-	.unmap_sg		= swiotlb_unmap_sg_attrs,
-	.map_page		= swiotlb_map_page,
-	.unmap_page		= swiotlb_unmap_page,
-	.dma_supported		= dma_direct_supported,
-};