diff options
Diffstat (limited to 'lib/dma-debug.c')
| -rw-r--r-- | lib/dma-debug.c | 1773 |
1 files changed, 0 insertions, 1773 deletions
diff --git a/lib/dma-debug.c b/lib/dma-debug.c deleted file mode 100644 index c007d25bee09..000000000000 --- 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); |