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lib/dma-debug.c
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/* * 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 */ |
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#include <linux/scatterlist.h> |
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#include <linux/dma-mapping.h> |
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#include <linux/stacktrace.h> |
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#include <linux/dma-debug.h> |
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#include <linux/spinlock.h> |
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#include <linux/debugfs.h> |
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#include <linux/uaccess.h> |
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#include <linux/device.h> |
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#include <linux/types.h> |
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#include <linux/sched.h> |
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#include <linux/ctype.h> |
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#include <linux/list.h> |
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#include <linux/slab.h> |
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#include <asm/sections.h> |
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#define HASH_SIZE 1024ULL #define HASH_FN_SHIFT 13 #define HASH_FN_MASK (HASH_SIZE - 1) |
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enum { dma_debug_single, dma_debug_page, dma_debug_sg, dma_debug_coherent, }; |
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#define DMA_DEBUG_STACKTRACE_ENTRIES 5 |
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struct dma_debug_entry { struct list_head list; struct device *dev; int type; phys_addr_t paddr; u64 dev_addr; u64 size; int direction; int sg_call_ents; int sg_mapped_ents; |
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#ifdef CONFIG_STACKTRACE struct stack_trace stacktrace; unsigned long st_entries[DMA_DEBUG_STACKTRACE_ENTRIES]; #endif |
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}; |
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struct hash_bucket { struct list_head list; spinlock_t lock; |
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} ____cacheline_aligned_in_smp; |
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/* Hash list to save the allocated dma addresses */ static struct hash_bucket dma_entry_hash[HASH_SIZE]; |
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/* 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; |
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/* 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; |
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static u32 num_free_entries; static u32 min_free_entries; |
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static u32 nr_total_entries; |
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/* number of preallocated entries requested by kernel cmdline */ static u32 req_entries; |
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/* 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; |
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static struct dentry *filter_dent __read_mostly; |
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/* 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); |
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static const char *type2name[4] = { "single", "page", "scather-gather", "coherent" }; static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE", "DMA_FROM_DEVICE", "DMA_NONE" }; |
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/* little merge helper - remove it after the merge window */ #ifndef BUS_NOTIFY_UNBOUND_DRIVER #define BUS_NOTIFY_UNBOUND_DRIVER 0x0005 #endif |
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/* * 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. */ |
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static inline void dump_entry_trace(struct dma_debug_entry *entry) { #ifdef CONFIG_STACKTRACE if (entry) { |
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pr_warning("Mapped at: "); |
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print_stack_trace(&entry->stacktrace, 0); } #endif } |
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static bool driver_filter(struct device *dev) { |
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struct device_driver *drv; unsigned long flags; bool ret; |
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/* driver filter off */ if (likely(!current_driver_name[0])) return true; /* driver filter on and initialized */ |
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if (current_driver && dev && dev->driver == current_driver) |
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return true; |
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/* driver filter on, but we can't filter on a NULL device... */ if (!dev) return false; |
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if (current_driver || !current_driver_name[0]) return false; |
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/* driver filter on but not yet initialized */ drv = get_driver(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; |
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} |
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read_unlock_irqrestore(&driver_name_lock, flags); put_driver(drv); return ret; |
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} |
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#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; \ |
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} while (0); |
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/* * 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) { 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) { unsigned long __flags = *flags; spin_unlock_irqrestore(&bucket->lock, __flags); } /* * 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) { |
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struct dma_debug_entry *entry, *ret = NULL; int matches = 0, match_lvl, last_lvl = 0; |
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list_for_each_entry(entry, &bucket->list, list) { |
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if ((entry->dev_addr != ref->dev_addr) || (entry->dev != ref->dev)) 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 |
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* positives being reported. Therefore we implement a |
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* 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; |
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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; |
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if (match_lvl == 4) { |
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/* perfect-fit - return the result */ |
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return entry; |
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} else if (match_lvl > last_lvl) { /* * We found an entry that fits better then the * previous one */ last_lvl = match_lvl; ret = entry; } |
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} |
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/* * If we have multiple matches but no perfect-fit, just return * NULL. */ ret = (matches == 1) ? ret : NULL; return ret; |
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} /* * 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); } /* |
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* 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 D=%Lx L=%Lx %s ", type2name[entry->type], idx, (unsigned long long)entry->paddr, entry->dev_addr, entry->size, dir2name[entry->direction]); } } spin_unlock_irqrestore(&bucket->lock, flags); } } EXPORT_SYMBOL(debug_dma_dump_mappings); /* |
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* 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; bucket = get_hash_bucket(entry, &flags); hash_bucket_add(bucket, entry); put_hash_bucket(bucket, &flags); } |
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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; } |
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/* 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 = NULL; unsigned long flags; spin_lock_irqsave(&free_entries_lock, flags); if (list_empty(&free_entries)) { |
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pr_err("DMA-API: debugging out of memory - disabling "); |
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global_disable = true; goto out; } |
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entry = __dma_entry_alloc(); |
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#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 |
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out: spin_unlock_irqrestore(&free_entries_lock, flags); return entry; } static void dma_entry_free(struct dma_debug_entry *entry) { unsigned long flags; /* * 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); } |
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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; } EXPORT_SYMBOL(dma_debug_resize_entries); |
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/* * 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; |
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pr_info("DMA-API: preallocated %d debug entries ", num_entries); |
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return 0; out_err: list_for_each_entry_safe(entry, next_entry, &free_entries, list) { list_del(&entry->list); kfree(entry); } return -ENOMEM; } |
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static ssize_t filter_read(struct file *file, char __user *user_buf, size_t count, loff_t *ppos) { |
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char buf[NAME_MAX_LEN + 1]; |
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unsigned long flags; |
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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 ", 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) { |
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char buf[NAME_MAX_LEN]; |
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unsigned long flags; size_t len; |
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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 */ |
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len = min(count, (size_t)(NAME_MAX_LEN - 1)); |
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if (copy_from_user(buf, userbuf, len)) return -EFAULT; buf[len] = 0; write_lock_irqsave(&driver_name_lock, flags); |
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/* * Now handle the string we got from userspace very carefully. |
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* The rules are: * - only use the first token we got * - token delimiter is everything looking like a space * character (' ', ' ', '\t' ...) * */ if (!isalnum(buf[0])) { /* |
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* If the first character userspace gave us is not |
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* alphanumerical then assume the filter should be * switched off. */ if (current_driver_name[0]) |
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pr_info("DMA-API: switching off dma-debug driver filter "); |
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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. */ |
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for (i = 0; i < NAME_MAX_LEN - 1; ++i) { |
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current_driver_name[i] = buf[i]; if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0) break; } current_driver_name[i] = 0; current_driver = NULL; |
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pr_info("DMA-API: enable driver filter for driver [%s] ", current_driver_name); |
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out_unlock: write_unlock_irqrestore(&driver_name_lock, flags); return count; } |
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static const struct file_operations filter_fops = { |
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.read = filter_read, .write = filter_write, }; |
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static int dma_debug_fs_init(void) { dma_debug_dent = debugfs_create_dir("dma-api", NULL); if (!dma_debug_dent) { |
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pr_err("DMA-API: can not create debugfs directory "); |
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return -ENOMEM; } global_disable_dent = debugfs_create_bool("disabled", 0444, dma_debug_dent, (u32 *)&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; |
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filter_dent = debugfs_create_file("driver_filter", 0644, dma_debug_dent, NULL, &filter_fops); if (!filter_dent) goto out_err; |
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return 0; out_err: debugfs_remove_recursive(dma_debug_dent); return -ENOMEM; } |
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static int device_dma_allocations(struct device *dev) { struct dma_debug_entry *entry; unsigned long flags; int count = 0, i; |
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local_irq_save(flags); |
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for (i = 0; i < HASH_SIZE; ++i) { |
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spin_lock(&dma_entry_hash[i].lock); |
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list_for_each_entry(entry, &dma_entry_hash[i].list, list) { if (entry->dev == dev) count += 1; } |
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spin_unlock(&dma_entry_hash[i].lock); |
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} |
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local_irq_restore(flags); |
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return count; } |
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static int dma_debug_device_change(struct notifier_block *nb, unsigned long action, void *data) |
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{ struct device *dev = data; int count; |
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if (global_disable) |
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return 0; |
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switch (action) { case BUS_NOTIFY_UNBOUND_DRIVER: count = device_dma_allocations(dev); if (count == 0) break; err_printk(dev, NULL, "DMA-API: device driver has pending " "DMA allocations while released from device " "[count=%d] ", count); break; default: break; } return 0; } |
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void dma_debug_add_bus(struct bus_type *bus) { |
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struct notifier_block *nb; |
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if (global_disable) return; |
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nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL); if (nb == NULL) { |
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pr_err("dma_debug_add_bus: out of memory "); |
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return; } nb->notifier_call = dma_debug_device_change; bus_register_notifier(bus, nb); |
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} |
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|
684 685 686 687 688 689 690 691 692 693 694 695 |
/* * Let the architectures decide how many entries should be preallocated. */ void dma_debug_init(u32 num_entries) { int i; if (global_disable) return; for (i = 0; i < HASH_SIZE; ++i) { INIT_LIST_HEAD(&dma_entry_hash[i].list); |
b0a5b83ee
|
696 |
spin_lock_init(&dma_entry_hash[i].lock); |
6bf078715
|
697 |
} |
788dcfa6f
|
698 |
if (dma_debug_fs_init() != 0) { |
e7ed70eed
|
699 700 |
pr_err("DMA-API: error creating debugfs entries - disabling "); |
788dcfa6f
|
701 702 703 704 |
global_disable = true; return; } |
59d3daafa
|
705 706 |
if (req_entries) num_entries = req_entries; |
6bf078715
|
707 |
if (prealloc_memory(num_entries) != 0) { |
e7ed70eed
|
708 709 |
pr_err("DMA-API: debugging out of memory error - disabled "); |
6bf078715
|
710 711 712 713 |
global_disable = true; return; } |
e6a1a89d5
|
714 |
nr_total_entries = num_free_entries; |
e7ed70eed
|
715 716 |
pr_info("DMA-API: debugging enabled by kernel config "); |
6bf078715
|
717 |
} |
59d3daafa
|
718 719 720 721 722 723 |
static __init int dma_debug_cmdline(char *str) { if (!str) return -EINVAL; if (strncmp(str, "off", 3) == 0) { |
e7ed70eed
|
724 725 |
pr_info("DMA-API: debugging disabled on kernel command line "); |
59d3daafa
|
726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 |
global_disable = true; } return 0; } static __init int dma_debug_entries_cmdline(char *str) { int res; if (!str) return -EINVAL; res = get_option(&str, &req_entries); if (!res) req_entries = 0; return 0; } __setup("dma_debug=", dma_debug_cmdline); __setup("dma_debug_entries=", dma_debug_entries_cmdline); |
2d62ece14
|
749 750 751 752 753 |
static void check_unmap(struct dma_debug_entry *ref) { struct dma_debug_entry *entry; struct hash_bucket *bucket; unsigned long flags; |
35d40952d
|
754 755 756 757 |
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 "); |
2d62ece14
|
758 |
return; |
35d40952d
|
759 |
} |
2d62ece14
|
760 761 762 763 764 |
bucket = get_hash_bucket(ref, &flags); entry = hash_bucket_find(bucket, ref); if (!entry) { |
6c132d1bc
|
765 |
err_printk(ref->dev, NULL, "DMA-API: device driver tries " |
2d62ece14
|
766 767 768 769 770 771 772 773 |
"to free DMA memory it has not allocated " "[device address=0x%016llx] [size=%llu bytes] ", ref->dev_addr, ref->size); goto out; } if (ref->size != entry->size) { |
6c132d1bc
|
774 |
err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece14
|
775 776 777 778 779 780 781 782 |
"DMA memory with different size " "[device address=0x%016llx] [map size=%llu bytes] " "[unmap size=%llu bytes] ", ref->dev_addr, entry->size, ref->size); } if (ref->type != entry->type) { |
6c132d1bc
|
783 |
err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece14
|
784 785 786 787 788 789 790 791 |
"DMA memory with wrong function " "[device address=0x%016llx] [size=%llu bytes] " "[mapped as %s] [unmapped as %s] ", ref->dev_addr, ref->size, type2name[entry->type], type2name[ref->type]); } else if ((entry->type == dma_debug_coherent) && (ref->paddr != entry->paddr)) { |
6c132d1bc
|
792 |
err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece14
|
793 794 |
"DMA memory with different CPU address " "[device address=0x%016llx] [size=%llu bytes] " |
59a40e704
|
795 796 |
"[cpu alloc address=0x%016llx] " "[cpu free address=0x%016llx]", |
2d62ece14
|
797 |
ref->dev_addr, ref->size, |
59a40e704
|
798 799 |
(unsigned long long)entry->paddr, (unsigned long long)ref->paddr); |
2d62ece14
|
800 801 802 803 |
} if (ref->sg_call_ents && ref->type == dma_debug_sg && ref->sg_call_ents != entry->sg_call_ents) { |
6c132d1bc
|
804 |
err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece14
|
805 806 807 808 809 810 811 812 813 814 815 |
"DMA sg list with different entry count " "[map count=%d] [unmap count=%d] ", 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) { |
6c132d1bc
|
816 |
err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece14
|
817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 |
"DMA memory with different direction " "[device address=0x%016llx] [size=%llu bytes] " "[mapped with %s] [unmapped with %s] ", ref->dev_addr, ref->size, dir2name[entry->direction], dir2name[ref->direction]); } hash_bucket_del(entry); dma_entry_free(entry); out: put_hash_bucket(bucket, &flags); } static void check_for_stack(struct device *dev, void *addr) { if (object_is_on_stack(addr)) |
6c132d1bc
|
836 837 838 |
err_printk(dev, NULL, "DMA-API: device driver maps memory from" "stack [addr=%p] ", addr); |
2d62ece14
|
839 |
} |
f39d1b979
|
840 |
static inline bool overlap(void *addr, unsigned long len, void *start, void *end) |
2e34bde18
|
841 |
{ |
f39d1b979
|
842 843 844 845 |
unsigned long a1 = (unsigned long)addr; unsigned long b1 = a1 + len; unsigned long a2 = (unsigned long)start; unsigned long b2 = (unsigned long)end; |
2e34bde18
|
846 |
|
f39d1b979
|
847 |
return !(b1 <= a2 || a1 >= b2); |
2e34bde18
|
848 |
} |
f39d1b979
|
849 |
static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len) |
2e34bde18
|
850 |
{ |
f39d1b979
|
851 852 853 854 |
if (overlap(addr, len, _text, _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] ", addr, len); |
2e34bde18
|
855 |
} |
aa010efb7
|
856 857 858 |
static void check_sync(struct device *dev, struct dma_debug_entry *ref, bool to_cpu) |
2d62ece14
|
859 |
{ |
2d62ece14
|
860 861 862 |
struct dma_debug_entry *entry; struct hash_bucket *bucket; unsigned long flags; |
aa010efb7
|
863 |
bucket = get_hash_bucket(ref, &flags); |
2d62ece14
|
864 |
|
aa010efb7
|
865 |
entry = hash_bucket_find(bucket, ref); |
2d62ece14
|
866 867 |
if (!entry) { |
6c132d1bc
|
868 |
err_printk(dev, NULL, "DMA-API: device driver tries " |
2d62ece14
|
869 870 871 |
"to sync DMA memory it has not allocated " "[device address=0x%016llx] [size=%llu bytes] ", |
aa010efb7
|
872 |
(unsigned long long)ref->dev_addr, ref->size); |
2d62ece14
|
873 874 |
goto out; } |
aa010efb7
|
875 |
if (ref->size > entry->size) { |
6c132d1bc
|
876 |
err_printk(dev, entry, "DMA-API: device driver syncs" |
2d62ece14
|
877 878 |
" DMA memory outside allocated range " "[device address=0x%016llx] " |
aa010efb7
|
879 880 881 882 883 |
"[allocation size=%llu bytes] " "[sync offset+size=%llu] ", entry->dev_addr, entry->size, ref->size); |
2d62ece14
|
884 |
} |
42d53b4ff
|
885 886 |
if (entry->direction == DMA_BIDIRECTIONAL) goto out; |
aa010efb7
|
887 |
if (ref->direction != entry->direction) { |
6c132d1bc
|
888 |
err_printk(dev, entry, "DMA-API: device driver syncs " |
2d62ece14
|
889 890 891 892 |
"DMA memory with different direction " "[device address=0x%016llx] [size=%llu bytes] " "[mapped with %s] [synced with %s] ", |
aa010efb7
|
893 |
(unsigned long long)ref->dev_addr, entry->size, |
2d62ece14
|
894 |
dir2name[entry->direction], |
aa010efb7
|
895 |
dir2name[ref->direction]); |
2d62ece14
|
896 |
} |
2d62ece14
|
897 |
if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) && |
aa010efb7
|
898 |
!(ref->direction == DMA_TO_DEVICE)) |
6c132d1bc
|
899 |
err_printk(dev, entry, "DMA-API: device driver syncs " |
2d62ece14
|
900 901 902 903 |
"device read-only DMA memory for cpu " "[device address=0x%016llx] [size=%llu bytes] " "[mapped with %s] [synced with %s] ", |
aa010efb7
|
904 |
(unsigned long long)ref->dev_addr, entry->size, |
2d62ece14
|
905 |
dir2name[entry->direction], |
aa010efb7
|
906 |
dir2name[ref->direction]); |
2d62ece14
|
907 908 |
if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) && |
aa010efb7
|
909 |
!(ref->direction == DMA_FROM_DEVICE)) |
6c132d1bc
|
910 |
err_printk(dev, entry, "DMA-API: device driver syncs " |
2d62ece14
|
911 912 913 914 |
"device write-only DMA memory to device " "[device address=0x%016llx] [size=%llu bytes] " "[mapped with %s] [synced with %s] ", |
aa010efb7
|
915 |
(unsigned long long)ref->dev_addr, entry->size, |
2d62ece14
|
916 |
dir2name[entry->direction], |
aa010efb7
|
917 |
dir2name[ref->direction]); |
2d62ece14
|
918 919 920 |
out: put_hash_bucket(bucket, &flags); |
2d62ece14
|
921 |
} |
f62bc980e
|
922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 |
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(global_disable)) return; if (unlikely(dma_mapping_error(dev, dma_addr))) return; entry = dma_entry_alloc(); if (!entry) return; entry->dev = dev; entry->type = dma_debug_page; entry->paddr = page_to_phys(page) + offset; entry->dev_addr = dma_addr; entry->size = size; entry->direction = direction; |
9537a48ed
|
944 |
if (map_single) |
f62bc980e
|
945 |
entry->type = dma_debug_single; |
9537a48ed
|
946 947 |
if (!PageHighMem(page)) { |
f39d1b979
|
948 |
void *addr = page_address(page) + offset; |
2e34bde18
|
949 950 |
check_for_stack(dev, addr); check_for_illegal_area(dev, addr, size); |
f62bc980e
|
951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 |
} add_dma_entry(entry); } EXPORT_SYMBOL(debug_dma_map_page); 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(global_disable)) return; if (map_single) ref.type = dma_debug_single; check_unmap(&ref); } EXPORT_SYMBOL(debug_dma_unmap_page); |
972aa45ce
|
977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 |
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(global_disable)) 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->paddr = sg_phys(s); |
884d05970
|
995 |
entry->size = sg_dma_len(s); |
15aedea43
|
996 |
entry->dev_addr = sg_dma_address(s); |
972aa45ce
|
997 998 999 |
entry->direction = direction; entry->sg_call_ents = nents; entry->sg_mapped_ents = mapped_ents; |
9537a48ed
|
1000 1001 |
if (!PageHighMem(sg_page(s))) { check_for_stack(dev, sg_virt(s)); |
884d05970
|
1002 |
check_for_illegal_area(dev, sg_virt(s), sg_dma_len(s)); |
9537a48ed
|
1003 |
} |
972aa45ce
|
1004 1005 1006 1007 1008 |
add_dma_entry(entry); } } EXPORT_SYMBOL(debug_dma_map_sg); |
aa010efb7
|
1009 1010 |
static int get_nr_mapped_entries(struct device *dev, struct dma_debug_entry *ref) |
88f3907f6
|
1011 |
{ |
aa010efb7
|
1012 |
struct dma_debug_entry *entry; |
88f3907f6
|
1013 1014 |
struct hash_bucket *bucket; unsigned long flags; |
c17e2cf73
|
1015 |
int mapped_ents; |
88f3907f6
|
1016 |
|
aa010efb7
|
1017 1018 |
bucket = get_hash_bucket(ref, &flags); entry = hash_bucket_find(bucket, ref); |
c17e2cf73
|
1019 |
mapped_ents = 0; |
88f3907f6
|
1020 |
|
88f3907f6
|
1021 1022 1023 1024 1025 1026 |
if (entry) mapped_ents = entry->sg_mapped_ents; put_hash_bucket(bucket, &flags); return mapped_ents; } |
972aa45ce
|
1027 1028 1029 |
void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nelems, int dir) { |
972aa45ce
|
1030 1031 |
struct scatterlist *s; int mapped_ents = 0, i; |
972aa45ce
|
1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 |
if (unlikely(global_disable)) return; for_each_sg(sglist, s, nelems, i) { struct dma_debug_entry ref = { .type = dma_debug_sg, .dev = dev, .paddr = sg_phys(s), |
15aedea43
|
1042 |
.dev_addr = sg_dma_address(s), |
884d05970
|
1043 |
.size = sg_dma_len(s), |
972aa45ce
|
1044 |
.direction = dir, |
e5e8c5b90
|
1045 |
.sg_call_ents = nelems, |
972aa45ce
|
1046 1047 1048 1049 |
}; if (mapped_ents && i >= mapped_ents) break; |
e5e8c5b90
|
1050 |
if (!i) |
aa010efb7
|
1051 |
mapped_ents = get_nr_mapped_entries(dev, &ref); |
972aa45ce
|
1052 1053 1054 1055 1056 |
check_unmap(&ref); } } EXPORT_SYMBOL(debug_dma_unmap_sg); |
6bfd44987
|
1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 |
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(global_disable)) return; if (unlikely(virt == NULL)) return; entry = dma_entry_alloc(); if (!entry) return; entry->type = dma_debug_coherent; entry->dev = dev; entry->paddr = virt_to_phys(virt); entry->size = size; entry->dev_addr = dma_addr; entry->direction = DMA_BIDIRECTIONAL; 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, .paddr = virt_to_phys(virt), .dev_addr = addr, .size = size, .direction = DMA_BIDIRECTIONAL, }; if (unlikely(global_disable)) return; check_unmap(&ref); } EXPORT_SYMBOL(debug_dma_free_coherent); |
b9d2317e0
|
1101 1102 1103 |
void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size, int direction) { |
aa010efb7
|
1104 |
struct dma_debug_entry ref; |
b9d2317e0
|
1105 1106 |
if (unlikely(global_disable)) return; |
aa010efb7
|
1107 1108 1109 1110 1111 1112 1113 1114 |
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); |
b9d2317e0
|
1115 1116 1117 1118 1119 1120 1121 |
} 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) { |
aa010efb7
|
1122 |
struct dma_debug_entry ref; |
b9d2317e0
|
1123 1124 |
if (unlikely(global_disable)) return; |
aa010efb7
|
1125 1126 1127 1128 1129 1130 1131 1132 |
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); |
b9d2317e0
|
1133 1134 |
} EXPORT_SYMBOL(debug_dma_sync_single_for_device); |
948408ba3
|
1135 1136 1137 1138 1139 |
void debug_dma_sync_single_range_for_cpu(struct device *dev, dma_addr_t dma_handle, unsigned long offset, size_t size, int direction) { |
aa010efb7
|
1140 |
struct dma_debug_entry ref; |
948408ba3
|
1141 1142 |
if (unlikely(global_disable)) return; |
aa010efb7
|
1143 1144 1145 1146 1147 1148 1149 1150 |
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); |
948408ba3
|
1151 1152 1153 1154 1155 1156 1157 1158 |
} 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) { |
aa010efb7
|
1159 |
struct dma_debug_entry ref; |
948408ba3
|
1160 1161 |
if (unlikely(global_disable)) return; |
aa010efb7
|
1162 1163 1164 1165 1166 1167 1168 1169 |
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); |
948408ba3
|
1170 1171 |
} EXPORT_SYMBOL(debug_dma_sync_single_range_for_device); |
a31fba5d6
|
1172 1173 1174 1175 |
void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems, int direction) { struct scatterlist *s; |
88f3907f6
|
1176 |
int mapped_ents = 0, i; |
a31fba5d6
|
1177 1178 1179 1180 1181 |
if (unlikely(global_disable)) return; for_each_sg(sg, s, nelems, i) { |
aa010efb7
|
1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 |
struct dma_debug_entry ref = { .type = dma_debug_sg, .dev = dev, .paddr = sg_phys(s), .dev_addr = sg_dma_address(s), .size = sg_dma_len(s), .direction = direction, .sg_call_ents = nelems, }; |
88f3907f6
|
1192 |
if (!i) |
aa010efb7
|
1193 |
mapped_ents = get_nr_mapped_entries(dev, &ref); |
88f3907f6
|
1194 1195 1196 |
if (i >= mapped_ents) break; |
aa010efb7
|
1197 |
check_sync(dev, &ref, true); |
a31fba5d6
|
1198 1199 1200 1201 1202 1203 1204 1205 |
} } 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; |
88f3907f6
|
1206 |
int mapped_ents = 0, i; |
a31fba5d6
|
1207 1208 1209 1210 1211 |
if (unlikely(global_disable)) return; for_each_sg(sg, s, nelems, i) { |
aa010efb7
|
1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 |
struct dma_debug_entry ref = { .type = dma_debug_sg, .dev = dev, .paddr = sg_phys(s), .dev_addr = sg_dma_address(s), .size = sg_dma_len(s), .direction = direction, .sg_call_ents = nelems, }; |
88f3907f6
|
1222 |
if (!i) |
aa010efb7
|
1223 |
mapped_ents = get_nr_mapped_entries(dev, &ref); |
88f3907f6
|
1224 1225 1226 |
if (i >= mapped_ents) break; |
aa010efb7
|
1227 |
check_sync(dev, &ref, false); |
a31fba5d6
|
1228 1229 1230 |
} } EXPORT_SYMBOL(debug_dma_sync_sg_for_device); |
1745de5e5
|
1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 |
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]) |
e7ed70eed
|
1242 1243 1244 |
pr_info("DMA-API: enable driver filter for driver [%s] ", current_driver_name); |
1745de5e5
|
1245 1246 1247 1248 1249 |
return 1; } __setup("dma_debug_driver=", dma_debug_driver_setup); |