linux/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
*/
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/stacktrace.h>
#include <linux/dma-debug.h>
#include <linux/spinlock.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)
enum {
dma_debug_single,
dma_debug_page,
dma_debug_sg,
dma_debug_coherent,
};
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 {
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;
enum map_err_types map_err_type;
#ifdef CONFIG_STACKTRACE
struct stack_trace stacktrace;
unsigned long st_entries[DMA_DEBUG_STACKTRACE_ENTRIES];
#endif
};
dma-debug: hash_bucket_find needs to allow for offsets within an entry Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-08-08 19:13:54 +00:00
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 u32 global_disable __read_mostly;
/* 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 req_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[4] = { "single", "page",
"scather-gather", "coherent" };
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)
{
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);
}
dma-debug: hash_bucket_find needs to allow for offsets within an entry Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-08-08 19:13:54 +00:00
static bool exact_match(struct dma_debug_entry *a, struct dma_debug_entry *b)
{
return ((a->dev_addr == b->dev_addr) &&
dma-debug: hash_bucket_find needs to allow for offsets within an entry Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-08-08 19:13:54 +00:00
(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
*/
dma-debug: hash_bucket_find needs to allow for offsets within an entry Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-08-08 19:13:54 +00:00
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) {
dma-debug: hash_bucket_find needs to allow for offsets within an entry Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-08-08 19:13:54 +00:00
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;
}
dma-debug: hash_bucket_find needs to allow for offsets within an entry Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-08-08 19:13:54 +00:00
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, &index, 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);
}
/*
* 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 %s\n",
type2name[entry->type], idx,
(unsigned long long)entry->paddr,
entry->dev_addr, entry->size,
dir2name[entry->direction],
maperr2str[entry->map_err_type]);
}
}
spin_unlock_irqrestore(&bucket->lock, flags);
}
}
EXPORT_SYMBOL(debug_dma_dump_mappings);
/*
* 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);
}
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)) {
pr_err("DMA-API: debugging out of memory - disabling\n");
global_disable = true;
spin_unlock_irqrestore(&free_entries_lock, flags);
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;
/*
* 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;
}
EXPORT_SYMBOL(dma_debug_resize_entries);
/*
* 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: automatically add .llseek fop All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-15 16:52:59 +00:00
.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;
local_irq_save(flags);
for (i = 0; i < HASH_SIZE; ++i) {
spin_lock(&dma_entry_hash[i].lock);
list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
if (entry->dev == dev) {
count += 1;
*out_entry = entry;
}
}
spin_unlock(&dma_entry_hash[i].lock);
}
local_irq_restore(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 (global_disable)
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 (global_disable)
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);
}
/*
* 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);
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;
}
if (req_entries)
num_entries = req_entries;
if (prealloc_memory(num_entries) != 0) {
pr_err("DMA-API: debugging out of memory error - disabled\n");
global_disable = true;
return;
}
nr_total_entries = num_free_entries;
pr_info("DMA-API: debugging enabled by kernel config\n");
}
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)
{
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);
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);
dma-debug: hash_bucket_find needs to allow for offsets within an entry Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-08-08 19:13:54 +00:00
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) &&
(ref->paddr != entry->paddr)) {
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,
(unsigned long long)entry->paddr,
(unsigned long long)ref->paddr);
}
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]);
}
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, void *addr)
{
if (object_is_on_stack(addr))
err_printk(dev, NULL, "DMA-API: device driver maps memory from"
"stack [addr=%p]\n", addr);
}
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, _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]\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);
dma-debug: hash_bucket_find needs to allow for offsets within an entry Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-08-08 19:13:54 +00:00
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]);
out:
put_hash_bucket(bucket, &flags);
}
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 (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;
entry->map_err_type = MAP_ERR_NOT_CHECKED;
if (map_single)
entry->type = dma_debug_single;
if (!PageHighMem(page)) {
void *addr = page_address(page) + offset;
check_for_stack(dev, addr);
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(global_disable))
return;
ref.dev = dev;
ref.dev_addr = dma_addr;
bucket = get_hash_bucket(&ref, &flags);
dma-debug: update DMA debug API to better handle multiple mappings of a buffer There were reports of the igb driver unmapping buffers without calling dma_mapping_error. On closer inspection issues were found in the DMA debug API and how it handled multiple mappings of the same buffer. The issue I found is the fact that the debug_dma_mapping_error would only set the map_err_type to MAP_ERR_CHECKED in the case that the was only one match for device and device address. However in the case of non-IOMMU, multiple addresses existed and as a result it was not setting this field once a second mapping was instantiated. I have resolved this by changing the search so that it instead will now set MAP_ERR_CHECKED on the first buffer that matches the device and DMA address that is currently in the state MAP_ERR_NOT_CHECKED. A secondary side effect of this patch is that in the case of multiple buffers using the same address only the last mapping will have a valid map_err_type. The previous mappings will all end up with map_err_type set to MAP_ERR_CHECKED because of the dma_mapping_error call in debug_dma_map_page. However this behavior may be preferable as it means you will likely only see one real error per multi-mapped buffer, versus the current behavior of multiple false errors mer multi-mapped buffer. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Reviewed-by: Shuah Khan <shuah.khan@hp.com> Tested-by: Shuah Khan <shuah.khan@hp.com> Cc: Jakub Kicinski <kubakici@wp.pl> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-03-22 22:04:49 +00:00
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(global_disable))
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(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);
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;
if (!PageHighMem(sg_page(s))) {
check_for_stack(dev, sg_virt(s));
check_for_illegal_area(dev, sg_virt(s), sg_dma_len(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);
dma-debug: hash_bucket_find needs to allow for offsets within an entry Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [<ffffffff81050f71>] warn_slowpath_common+0x85/0x9d [<ffffffff8105102c>] warn_slowpath_fmt+0x46/0x48 [<ffffffff8124658e>] ? check_sync+0x39/0x48c [<ffffffff8107c470>] ? trace_hardirqs_on+0xd/0xf [<ffffffff81246632>] check_sync+0xdd/0x48c [<ffffffff81246ca6>] debug_dma_sync_single_for_device+0x3f/0x41 [<ffffffffa011615c>] ? pci_map_page+0x84/0x97 [cxgb3] [<ffffffffa0117bc3>] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [<ffffffffa0117ed1>] refill_fl+0x305/0x30a [cxgb3] [<ffffffffa011857d>] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [<ffffffffa010a07b>] cxgb_up+0x4d0/0xe62 [cxgb3] [<ffffffff81086037>] ? __module_text_address+0x12/0x58 [<ffffffffa010aa4c>] cxgb_open+0x3f/0x309 [cxgb3] [<ffffffff813e9f6c>] __dev_open+0x8e/0xbc [<ffffffff813e7ca5>] __dev_change_flags+0xbe/0x142 [<ffffffff813e9ea8>] dev_change_flags+0x21/0x57 [<ffffffff81445937>] devinet_ioctl+0x29a/0x54b [<ffffffff811f9a87>] ? inode_has_perm+0xaa/0xce [<ffffffff81446ed2>] inet_ioctl+0x8f/0xa7 [<ffffffff813d683a>] sock_do_ioctl+0x29/0x48 [<ffffffff813d6c83>] sock_ioctl+0x213/0x222 [<ffffffff81137f78>] vfs_ioctl+0x32/0xa6 [<ffffffff811384e2>] do_vfs_ioctl+0x47a/0x4b3 [<ffffffff81138571>] sys_ioctl+0x56/0x79 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jay Fenalson <fenlason@redhat.com> CC: Divy LeRay <divy@chelsio.com> CC: Stanislaw Gruszka <sgruszka@redhat.com> CC: Joerg Roedel <joerg.roedel@amd.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-08-08 19:13:54 +00:00
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(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),
.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(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);
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(global_disable))
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(global_disable))
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(global_disable))
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(global_disable))
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(global_disable))
return;
for_each_sg(sg, s, nelems, i) {
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,
};
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(global_disable))
return;
for_each_sg(sg, s, nelems, i) {
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,
};
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);