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Commit 9fcbbac5 authored by David Fries's avatar David Fries Committed by Greg Kroah-Hartman
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w1: process w1 netlink commands in w1_process thread 

Netlink is a socket interface and is expected to be asynchronous.
Clients can now make w1 requests without blocking by making use of the
w1_master thread to process netlink commands which was previously only
used for doing an automatic bus search.
Signed-off-by: default avatarDavid Fries <David@Fries.net>
Acked-by: default avatarEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 70b34d2e
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Showing with 300 additions and 95 deletions
drivers/w1/w1.c
View file @ 9fcbbac5
...@@ -79,19 +79,10 @@ static void w1_slave_release(struct device *dev) ...@@ -79,19 +79,10 @@ static void w1_slave_release(struct device *dev)
{ {
struct w1_slave *sl = dev_to_w1_slave(dev); struct w1_slave *sl = dev_to_w1_slave(dev);
dev_dbg(dev, "%s: Releasing %s.\n", __func__, sl->name); dev_dbg(dev, "%s: Releasing %s [%p]\n", __func__, sl->name, sl);
while (atomic_read(&sl->refcnt)) {
dev_dbg(dev, "Waiting for %s to become free: refcnt=%d.\n",
sl->name, atomic_read(&sl->refcnt));
if (msleep_interruptible(1000))
flush_signals(current);
}
w1_family_put(sl->family); w1_family_put(sl->family);
sl->master->slave_count--; sl->master->slave_count--;
complete(&sl->released);
} }
static ssize_t name_show(struct device *dev, struct device_attribute *attr, char *buf) static ssize_t name_show(struct device *dev, struct device_attribute *attr, char *buf)
...@@ -277,7 +268,6 @@ static ssize_t w1_master_attribute_store_pullup(struct device *dev, ...@@ -277,7 +268,6 @@ static ssize_t w1_master_attribute_store_pullup(struct device *dev,
mutex_lock(&md->mutex); mutex_lock(&md->mutex);
md->enable_pullup = tmp; md->enable_pullup = tmp;
mutex_unlock(&md->mutex); mutex_unlock(&md->mutex);
wake_up_process(md->thread);
return count; return count;
} }
...@@ -370,23 +360,20 @@ static ssize_t w1_master_attribute_show_slaves(struct device *dev, ...@@ -370,23 +360,20 @@ static ssize_t w1_master_attribute_show_slaves(struct device *dev,
{ {
struct w1_master *md = dev_to_w1_master(dev); struct w1_master *md = dev_to_w1_master(dev);
int c = PAGE_SIZE; int c = PAGE_SIZE;
struct list_head *ent, *n;
struct w1_slave *sl = NULL;
mutex_lock(&md->mutex); mutex_lock(&md->list_mutex);
if (md->slave_count == 0)
c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n");
else {
struct list_head *ent, *n;
struct w1_slave *sl;
list_for_each_safe(ent, n, &md->slist) { list_for_each_safe(ent, n, &md->slist) {
sl = list_entry(ent, struct w1_slave, w1_slave_entry); sl = list_entry(ent, struct w1_slave, w1_slave_entry);
c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name); c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name);
}
} }
if (!sl)
c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n");
mutex_unlock(&md->mutex); mutex_unlock(&md->list_mutex);
return PAGE_SIZE - c; return PAGE_SIZE - c;
} }
...@@ -440,19 +427,22 @@ static int w1_atoreg_num(struct device *dev, const char *buf, size_t count, ...@@ -440,19 +427,22 @@ static int w1_atoreg_num(struct device *dev, const char *buf, size_t count,
} }
/* Searches the slaves in the w1_master and returns a pointer or NULL. /* Searches the slaves in the w1_master and returns a pointer or NULL.
* Note: must hold the mutex * Note: must not hold list_mutex
*/ */
struct w1_slave *w1_slave_search_device(struct w1_master *dev, struct w1_slave *w1_slave_search_device(struct w1_master *dev,
struct w1_reg_num *rn) struct w1_reg_num *rn)
{ {
struct w1_slave *sl; struct w1_slave *sl;
mutex_lock(&dev->list_mutex);
list_for_each_entry(sl, &dev->slist, w1_slave_entry) { list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
if (sl->reg_num.family == rn->family && if (sl->reg_num.family == rn->family &&
sl->reg_num.id == rn->id && sl->reg_num.id == rn->id &&
sl->reg_num.crc == rn->crc) { sl->reg_num.crc == rn->crc) {
mutex_unlock(&dev->list_mutex);
return sl; return sl;
} }
} }
mutex_unlock(&dev->list_mutex);
return NULL; return NULL;
} }
...@@ -509,7 +499,10 @@ static ssize_t w1_master_attribute_store_remove(struct device *dev, ...@@ -509,7 +499,10 @@ static ssize_t w1_master_attribute_store_remove(struct device *dev,
mutex_lock(&md->mutex); mutex_lock(&md->mutex);
sl = w1_slave_search_device(md, &rn); sl = w1_slave_search_device(md, &rn);
if (sl) { if (sl) {
w1_slave_detach(sl); result = w1_slave_detach(sl);
/* refcnt 0 means it was detached in the call */
if (result == 0)
result = count;
} else { } else {
dev_info(dev, "Device %02x-%012llx doesn't exists\n", rn.family, dev_info(dev, "Device %02x-%012llx doesn't exists\n", rn.family,
(unsigned long long)rn.id); (unsigned long long)rn.id);
...@@ -704,7 +697,9 @@ static int __w1_attach_slave_device(struct w1_slave *sl) ...@@ -704,7 +697,9 @@ static int __w1_attach_slave_device(struct w1_slave *sl)
dev_set_uevent_suppress(&sl->dev, false); dev_set_uevent_suppress(&sl->dev, false);
kobject_uevent(&sl->dev.kobj, KOBJ_ADD); kobject_uevent(&sl->dev.kobj, KOBJ_ADD);
mutex_lock(&sl->master->list_mutex);
list_add_tail(&sl->w1_slave_entry, &sl->master->slist); list_add_tail(&sl->w1_slave_entry, &sl->master->slist);
mutex_unlock(&sl->master->list_mutex);
return 0; return 0;
} }
...@@ -731,8 +726,8 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn) ...@@ -731,8 +726,8 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
memset(&msg, 0, sizeof(msg)); memset(&msg, 0, sizeof(msg));
memcpy(&sl->reg_num, rn, sizeof(sl->reg_num)); memcpy(&sl->reg_num, rn, sizeof(sl->reg_num));
atomic_set(&sl->refcnt, 0); atomic_set(&sl->refcnt, 1);
init_completion(&sl->released); atomic_inc(&sl->master->refcnt);
/* slave modules need to be loaded in a context with unlocked mutex */ /* slave modules need to be loaded in a context with unlocked mutex */
mutex_unlock(&dev->mutex); mutex_unlock(&dev->mutex);
...@@ -772,23 +767,48 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn) ...@@ -772,23 +767,48 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
return 0; return 0;
} }
void w1_slave_detach(struct w1_slave *sl) int w1_unref_slave(struct w1_slave *sl)
{ {
struct w1_netlink_msg msg; struct w1_master *dev = sl->master;
int refcnt;
dev_dbg(&sl->dev, "%s: detaching %s [%p].\n", __func__, sl->name, sl); mutex_lock(&dev->list_mutex);
refcnt = atomic_sub_return(1, &sl->refcnt);
list_del(&sl->w1_slave_entry); if (refcnt == 0) {
struct w1_netlink_msg msg;
memset(&msg, 0, sizeof(msg));
memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id)); dev_dbg(&sl->dev, "%s: detaching %s [%p].\n", __func__,
msg.type = W1_SLAVE_REMOVE; sl->name, sl);
w1_netlink_send(sl->master, &msg);
list_del(&sl->w1_slave_entry);
device_unregister(&sl->dev);
memset(&msg, 0, sizeof(msg));
memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id));
msg.type = W1_SLAVE_REMOVE;
w1_netlink_send(sl->master, &msg);
device_unregister(&sl->dev);
#ifdef DEBUG
memset(sl, 0, sizeof(*sl));
#endif
kfree(sl);
}
atomic_dec(&dev->refcnt);
mutex_unlock(&dev->list_mutex);
return refcnt;
}
wait_for_completion(&sl->released); int w1_slave_detach(struct w1_slave *sl)
kfree(sl); {
/* Only detach a slave once as it decreases the refcnt each time. */
int destroy_now;
mutex_lock(&sl->master->list_mutex);
destroy_now = !test_bit(W1_SLAVE_DETACH, &sl->flags);
set_bit(W1_SLAVE_DETACH, &sl->flags);
mutex_unlock(&sl->master->list_mutex);
if (destroy_now)
destroy_now = !w1_unref_slave(sl);
return destroy_now ? 0 : -EBUSY;
} }
struct w1_master *w1_search_master_id(u32 id) struct w1_master *w1_search_master_id(u32 id)
...@@ -817,7 +837,7 @@ struct w1_slave *w1_search_slave(struct w1_reg_num *id) ...@@ -817,7 +837,7 @@ struct w1_slave *w1_search_slave(struct w1_reg_num *id)
mutex_lock(&w1_mlock); mutex_lock(&w1_mlock);
list_for_each_entry(dev, &w1_masters, w1_master_entry) { list_for_each_entry(dev, &w1_masters, w1_master_entry) {
mutex_lock(&dev->mutex); mutex_lock(&dev->list_mutex);
list_for_each_entry(sl, &dev->slist, w1_slave_entry) { list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
if (sl->reg_num.family == id->family && if (sl->reg_num.family == id->family &&
sl->reg_num.id == id->id && sl->reg_num.id == id->id &&
...@@ -828,7 +848,7 @@ struct w1_slave *w1_search_slave(struct w1_reg_num *id) ...@@ -828,7 +848,7 @@ struct w1_slave *w1_search_slave(struct w1_reg_num *id)
break; break;
} }
} }
mutex_unlock(&dev->mutex); mutex_unlock(&dev->list_mutex);
if (found) if (found)
break; break;
...@@ -848,6 +868,7 @@ void w1_reconnect_slaves(struct w1_family *f, int attach) ...@@ -848,6 +868,7 @@ void w1_reconnect_slaves(struct w1_family *f, int attach)
dev_dbg(&dev->dev, "Reconnecting slaves in device %s " dev_dbg(&dev->dev, "Reconnecting slaves in device %s "
"for family %02x.\n", dev->name, f->fid); "for family %02x.\n", dev->name, f->fid);
mutex_lock(&dev->mutex); mutex_lock(&dev->mutex);
mutex_lock(&dev->list_mutex);
list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
/* If it is a new family, slaves with the default /* If it is a new family, slaves with the default
* family driver and are that family will be * family driver and are that family will be
...@@ -859,14 +880,19 @@ void w1_reconnect_slaves(struct w1_family *f, int attach) ...@@ -859,14 +880,19 @@ void w1_reconnect_slaves(struct w1_family *f, int attach)
(!attach && sl->family->fid == f->fid)) { (!attach && sl->family->fid == f->fid)) {
struct w1_reg_num rn; struct w1_reg_num rn;
mutex_unlock(&dev->list_mutex);
memcpy(&rn, &sl->reg_num, sizeof(rn)); memcpy(&rn, &sl->reg_num, sizeof(rn));
w1_slave_detach(sl); /* If it was already in use let the automatic
* scan pick it up again later.
w1_attach_slave_device(dev, &rn); */
if (!w1_slave_detach(sl))
w1_attach_slave_device(dev, &rn);
mutex_lock(&dev->list_mutex);
} }
} }
dev_dbg(&dev->dev, "Reconnecting slaves in device %s " dev_dbg(&dev->dev, "Reconnecting slaves in device %s "
"has been finished.\n", dev->name); "has been finished.\n", dev->name);
mutex_unlock(&dev->list_mutex);
mutex_unlock(&dev->mutex); mutex_unlock(&dev->mutex);
} }
mutex_unlock(&w1_mlock); mutex_unlock(&w1_mlock);
...@@ -1020,17 +1046,24 @@ void w1_search_process_cb(struct w1_master *dev, u8 search_type, ...@@ -1020,17 +1046,24 @@ void w1_search_process_cb(struct w1_master *dev, u8 search_type,
{ {
struct w1_slave *sl, *sln; struct w1_slave *sl, *sln;
mutex_lock(&dev->list_mutex);
list_for_each_entry(sl, &dev->slist, w1_slave_entry) list_for_each_entry(sl, &dev->slist, w1_slave_entry)
clear_bit(W1_SLAVE_ACTIVE, &sl->flags); clear_bit(W1_SLAVE_ACTIVE, &sl->flags);
mutex_unlock(&dev->list_mutex);
w1_search_devices(dev, search_type, cb); w1_search_devices(dev, search_type, cb);
mutex_lock(&dev->list_mutex);
list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
if (!test_bit(W1_SLAVE_ACTIVE, &sl->flags) && !--sl->ttl) if (!test_bit(W1_SLAVE_ACTIVE, &sl->flags) && !--sl->ttl) {
mutex_unlock(&dev->list_mutex);
w1_slave_detach(sl); w1_slave_detach(sl);
mutex_lock(&dev->list_mutex);
}
else if (test_bit(W1_SLAVE_ACTIVE, &sl->flags)) else if (test_bit(W1_SLAVE_ACTIVE, &sl->flags))
sl->ttl = dev->slave_ttl; sl->ttl = dev->slave_ttl;
} }
mutex_unlock(&dev->list_mutex);
if (dev->search_count > 0) if (dev->search_count > 0)
dev->search_count--; dev->search_count--;
...@@ -1041,6 +1074,26 @@ static void w1_search_process(struct w1_master *dev, u8 search_type) ...@@ -1041,6 +1074,26 @@ static void w1_search_process(struct w1_master *dev, u8 search_type)
w1_search_process_cb(dev, search_type, w1_slave_found); w1_search_process_cb(dev, search_type, w1_slave_found);
} }
int w1_process_callbacks(struct w1_master *dev)
{
int ret = 0;
struct w1_async_cmd *async_cmd, *async_n;
/* The list can be added to in another thread, loop until it is empty */
while (!list_empty(&dev->async_list)) {
list_for_each_entry_safe(async_cmd, async_n, &dev->async_list,
async_entry) {
/* drop the lock, if it is a search it can take a long
* time */
mutex_unlock(&dev->list_mutex);
async_cmd->cb(dev, async_cmd);
ret = 1;
mutex_lock(&dev->list_mutex);
}
}
return ret;
}
int w1_process(void *data) int w1_process(void *data)
{ {
struct w1_master *dev = (struct w1_master *) data; struct w1_master *dev = (struct w1_master *) data;
...@@ -1048,23 +1101,46 @@ int w1_process(void *data) ...@@ -1048,23 +1101,46 @@ int w1_process(void *data)
* time can be calculated in jiffies once. * time can be calculated in jiffies once.
*/ */
const unsigned long jtime = msecs_to_jiffies(w1_timeout * 1000); const unsigned long jtime = msecs_to_jiffies(w1_timeout * 1000);
/* remainder if it woke up early */
unsigned long jremain = 0;
while (!kthread_should_stop()) { for (;;) {
if (dev->search_count) {
if (!jremain && dev->search_count) {
mutex_lock(&dev->mutex); mutex_lock(&dev->mutex);
w1_search_process(dev, W1_SEARCH); w1_search_process(dev, W1_SEARCH);
mutex_unlock(&dev->mutex); mutex_unlock(&dev->mutex);
} }
mutex_lock(&dev->list_mutex);
/* Note, w1_process_callback drops the lock while processing,
* but locks it again before returning.
*/
if (!w1_process_callbacks(dev) && jremain) {
/* a wake up is either to stop the thread, process
* callbacks, or search, it isn't process callbacks, so
* schedule a search.
*/
jremain = 1;
}
try_to_freeze(); try_to_freeze();
__set_current_state(TASK_INTERRUPTIBLE); __set_current_state(TASK_INTERRUPTIBLE);
/* hold list_mutex until after interruptible to prevent loosing
* the wakeup signal when async_cmd is added.
*/
mutex_unlock(&dev->list_mutex);
if (kthread_should_stop()) if (kthread_should_stop())
break; break;
/* Only sleep when the search is active. */ /* Only sleep when the search is active. */
if (dev->search_count) if (dev->search_count) {
schedule_timeout(jtime); if (!jremain)
jremain = jtime;
jremain = schedule_timeout(jremain);
}
else else
schedule(); schedule();
} }
......
drivers/w1/w1.h
View file @ 9fcbbac5
...@@ -58,6 +58,7 @@ struct w1_reg_num ...@@ -58,6 +58,7 @@ struct w1_reg_num
#define W1_RESUME_CMD 0xA5 #define W1_RESUME_CMD 0xA5
#define W1_SLAVE_ACTIVE 0 #define W1_SLAVE_ACTIVE 0
#define W1_SLAVE_DETACH 1
struct w1_slave struct w1_slave
{ {
...@@ -74,7 +75,6 @@ struct w1_slave ...@@ -74,7 +75,6 @@ struct w1_slave
struct w1_family *family; struct w1_family *family;
void *family_data; void *family_data;
struct device dev; struct device dev;
struct completion released;
}; };
typedef void (*w1_slave_found_callback)(struct w1_master *, u64); typedef void (*w1_slave_found_callback)(struct w1_master *, u64);
...@@ -171,7 +171,14 @@ struct w1_master ...@@ -171,7 +171,14 @@ struct w1_master
struct list_head w1_master_entry; struct list_head w1_master_entry;
struct module *owner; struct module *owner;
unsigned char name[W1_MAXNAMELEN]; unsigned char name[W1_MAXNAMELEN];
/* list_mutex protects just slist and async_list so slaves can be
* searched for and async commands added while the master has
* w1_master.mutex locked and is operating on the bus.
* lock order w1_mlock, w1_master.mutex, w1_master_list_mutex
*/
struct mutex list_mutex;
struct list_head slist; struct list_head slist;
struct list_head async_list;
int max_slave_count, slave_count; int max_slave_count, slave_count;
unsigned long attempts; unsigned long attempts;
int slave_ttl; int slave_ttl;
...@@ -205,11 +212,29 @@ struct w1_master ...@@ -205,11 +212,29 @@ struct w1_master
u32 seq; u32 seq;
}; };
/**
* struct w1_async_cmd - execute callback from the w1_process kthread
* @async_entry: link entry
* @cb: callback function, must list_del and destroy this list before
* returning
*
* When inserted into the w1_master async_list, w1_process will execute
* the callback. Embed this into the structure with the command details.
*/
struct w1_async_cmd {
struct list_head async_entry;
void (*cb)(struct w1_master *dev, struct w1_async_cmd *async_cmd);
};
int w1_create_master_attributes(struct w1_master *); int w1_create_master_attributes(struct w1_master *);
void w1_destroy_master_attributes(struct w1_master *master); void w1_destroy_master_attributes(struct w1_master *master);
void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb); void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb); void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb);
/* call w1_unref_slave to release the reference counts w1_search_slave added */
struct w1_slave *w1_search_slave(struct w1_reg_num *id); struct w1_slave *w1_search_slave(struct w1_reg_num *id);
/* decrements the reference on sl->master and sl, and cleans up if zero
* returns the reference count after it has been decremented */
int w1_unref_slave(struct w1_slave *sl);
void w1_slave_found(struct w1_master *dev, u64 rn); void w1_slave_found(struct w1_master *dev, u64 rn);
void w1_search_process_cb(struct w1_master *dev, u8 search_type, void w1_search_process_cb(struct w1_master *dev, u8 search_type,
w1_slave_found_callback cb); w1_slave_found_callback cb);
...@@ -224,7 +249,8 @@ struct w1_master *w1_search_master_id(u32 id); ...@@ -224,7 +249,8 @@ struct w1_master *w1_search_master_id(u32 id);
*/ */
void w1_reconnect_slaves(struct w1_family *f, int attach); void w1_reconnect_slaves(struct w1_family *f, int attach);
int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn); int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn);
void w1_slave_detach(struct w1_slave *sl); /* 0 success, otherwise EBUSY */
int w1_slave_detach(struct w1_slave *sl);
u8 w1_triplet(struct w1_master *dev, int bdir); u8 w1_triplet(struct w1_master *dev, int bdir);
void w1_write_8(struct w1_master *, u8); void w1_write_8(struct w1_master *, u8);
...@@ -260,6 +286,8 @@ extern int w1_max_slave_ttl; ...@@ -260,6 +286,8 @@ extern int w1_max_slave_ttl;
extern struct list_head w1_masters; extern struct list_head w1_masters;
extern struct mutex w1_mlock; extern struct mutex w1_mlock;
/* returns 1 if there were commands to executed 0 otherwise */
extern int w1_process_callbacks(struct w1_master *dev);
extern int w1_process(void *); extern int w1_process(void *);
#endif /* __KERNEL__ */ #endif /* __KERNEL__ */
......
drivers/w1/w1_int.c
View file @ 9fcbbac5
...@@ -75,8 +75,10 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl, ...@@ -75,8 +75,10 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
atomic_set(&dev->refcnt, 2); atomic_set(&dev->refcnt, 2);
INIT_LIST_HEAD(&dev->slist); INIT_LIST_HEAD(&dev->slist);
INIT_LIST_HEAD(&dev->async_list);
mutex_init(&dev->mutex); mutex_init(&dev->mutex);
mutex_init(&dev->bus_mutex); mutex_init(&dev->bus_mutex);
mutex_init(&dev->list_mutex);
memcpy(&dev->dev, device, sizeof(struct device)); memcpy(&dev->dev, device, sizeof(struct device));
dev_set_name(&dev->dev, "w1_bus_master%u", dev->id); dev_set_name(&dev->dev, "w1_bus_master%u", dev->id);
...@@ -188,17 +190,22 @@ void __w1_remove_master_device(struct w1_master *dev) ...@@ -188,17 +190,22 @@ void __w1_remove_master_device(struct w1_master *dev)
struct w1_netlink_msg msg; struct w1_netlink_msg msg;
struct w1_slave *sl, *sln; struct w1_slave *sl, *sln;
set_bit(W1_ABORT_SEARCH, &dev->flags);
kthread_stop(dev->thread);
mutex_lock(&w1_mlock); mutex_lock(&w1_mlock);
list_del(&dev->w1_master_entry); list_del(&dev->w1_master_entry);
mutex_unlock(&w1_mlock); mutex_unlock(&w1_mlock);
set_bit(W1_ABORT_SEARCH, &dev->flags);
kthread_stop(dev->thread);
mutex_lock(&dev->mutex); mutex_lock(&dev->mutex);
list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) mutex_lock(&dev->list_mutex);
list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
mutex_unlock(&dev->list_mutex);
w1_slave_detach(sl); w1_slave_detach(sl);
mutex_lock(&dev->list_mutex);
}
w1_destroy_master_attributes(dev); w1_destroy_master_attributes(dev);
mutex_unlock(&dev->list_mutex);
mutex_unlock(&dev->mutex); mutex_unlock(&dev->mutex);
atomic_dec(&dev->refcnt); atomic_dec(&dev->refcnt);
...@@ -208,7 +215,9 @@ void __w1_remove_master_device(struct w1_master *dev) ...@@ -208,7 +215,9 @@ void __w1_remove_master_device(struct w1_master *dev)
if (msleep_interruptible(1000)) if (msleep_interruptible(1000))
flush_signals(current); flush_signals(current);
w1_process_callbacks(dev);
} }
w1_process_callbacks(dev);
memset(&msg, 0, sizeof(msg)); memset(&msg, 0, sizeof(msg));
msg.id.mst.id = dev->id; msg.id.mst.id = dev->id;
......
drivers/w1/w1_netlink.c
View file @ 9fcbbac5
...@@ -119,10 +119,12 @@ static int w1_get_slaves(struct w1_master *dev, ...@@ -119,10 +119,12 @@ static int w1_get_slaves(struct w1_master *dev,
if (req_cmd->cmd == W1_CMD_LIST_SLAVES) { if (req_cmd->cmd == W1_CMD_LIST_SLAVES) {
__u64 rn; __u64 rn;
mutex_lock(&dev->list_mutex);
list_for_each_entry(sl, &dev->slist, w1_slave_entry) { list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
memcpy(&rn, &sl->reg_num, sizeof(rn)); memcpy(&rn, &sl->reg_num, sizeof(rn));
w1_send_slave(dev, rn); w1_send_slave(dev, rn);
} }
mutex_unlock(&dev->list_mutex);
} else { } else {
w1_search_process_cb(dev, cmd->cmd == W1_CMD_ALARM_SEARCH ? w1_search_process_cb(dev, cmd->cmd == W1_CMD_ALARM_SEARCH ?
W1_ALARM_SEARCH : W1_SEARCH, w1_found_send_slave); W1_ALARM_SEARCH : W1_SEARCH, w1_found_send_slave);
...@@ -368,29 +370,134 @@ static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rm ...@@ -368,29 +370,134 @@ static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rm
return error; return error;
} }
/* Bundle together a reference count, the full message, and broken out
* commands to be executed on each w1 master kthread in one memory allocation.
*/
struct w1_cb_block {
atomic_t refcnt;
struct cn_msg msg;
/* cn_msg data */
/* one or more variable length struct w1_cb_node */
};
struct w1_cb_node {
struct w1_async_cmd async;
/* pointers within w1_cb_block and msg data */
struct w1_cb_block *block;
struct w1_netlink_msg *m;
struct w1_slave *sl;
struct w1_master *dev;
};
static void w1_process_cb(struct w1_master *dev, struct w1_async_cmd *async_cmd)
{
struct w1_cb_node *node = container_of(async_cmd, struct w1_cb_node,
async);
u16 mlen = node->m->len;
u8 *cmd_data = node->m->data;
int err = 0;
struct w1_slave *sl = node->sl;
struct w1_netlink_cmd *cmd = NULL;
mutex_lock(&dev->mutex);
if (sl && w1_reset_select_slave(sl))
err = -ENODEV;
while (mlen && !err) {
cmd = (struct w1_netlink_cmd *)cmd_data;
if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
err = -E2BIG;
break;
}
if (sl)
err = w1_process_command_slave(sl, &node->block->msg,
node->m, cmd);
else
err = w1_process_command_master(dev, &node->block->msg,
node->m, cmd);
w1_netlink_send_error(&node->block->msg, node->m, cmd, err);
err = 0;
cmd_data += cmd->len + sizeof(struct w1_netlink_cmd);
mlen -= cmd->len + sizeof(struct w1_netlink_cmd);
}
if (!cmd || err)
w1_netlink_send_error(&node->block->msg, node->m, cmd, err);
if (sl)
w1_unref_slave(sl);
else
atomic_dec(&dev->refcnt);
mutex_unlock(&dev->mutex);
mutex_lock(&dev->list_mutex);
list_del(&async_cmd->async_entry);
mutex_unlock(&dev->list_mutex);
if (atomic_sub_return(1, &node->block->refcnt) == 0)
kfree(node->block);
}
static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp) static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
{ {
struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1); struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1);
struct w1_netlink_cmd *cmd;
struct w1_slave *sl; struct w1_slave *sl;
struct w1_master *dev; struct w1_master *dev;
u16 msg_len;
int err = 0; int err = 0;
struct w1_cb_block *block = NULL;
struct w1_cb_node *node = NULL;
int node_count = 0;
/* Count the number of master or slave commands there are to allocate
* space for one cb_node each.
*/
msg_len = msg->len;
while (msg_len && !err) {
if (m->len + sizeof(struct w1_netlink_msg) > msg_len) {
err = -E2BIG;
break;
}
if (m->type == W1_MASTER_CMD || m->type == W1_SLAVE_CMD)
++node_count;
msg_len -= sizeof(struct w1_netlink_msg) + m->len;
m = (struct w1_netlink_msg *)(((u8 *)m) +
sizeof(struct w1_netlink_msg) + m->len);
}
m = (struct w1_netlink_msg *)(msg + 1);
if (node_count) {
/* msg->len doesn't include itself */
long size = sizeof(struct w1_cb_block) + msg->len +
node_count*sizeof(struct w1_cb_node);
block = kmalloc(size, GFP_KERNEL);
if (!block) {
w1_netlink_send_error(msg, m, NULL, -ENOMEM);
return;
}
atomic_set(&block->refcnt, 1);
memcpy(&block->msg, msg, sizeof(*msg) + msg->len);
node = (struct w1_cb_node *)((u8 *)block->msg.data + msg->len);
}
while (msg->len && !err) { msg_len = msg->len;
while (msg_len && !err) {
struct w1_reg_num id; struct w1_reg_num id;
u16 mlen = m->len; u16 mlen = m->len;
u8 *cmd_data = m->data;
dev = NULL; dev = NULL;
sl = NULL; sl = NULL;
cmd = NULL;
memcpy(&id, m->id.id, sizeof(id)); memcpy(&id, m->id.id, sizeof(id));
#if 0 #if 0
printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n", printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n",
__func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len); __func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len);
#endif #endif
if (m->len + sizeof(struct w1_netlink_msg) > msg->len) { if (m->len + sizeof(struct w1_netlink_msg) > msg_len) {
err = -E2BIG; err = -E2BIG;
break; break;
} }
...@@ -415,41 +522,24 @@ static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp) ...@@ -415,41 +522,24 @@ static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
if (!mlen) if (!mlen)
goto out_cont; goto out_cont;
mutex_lock(&dev->mutex); atomic_inc(&block->refcnt);
node->async.cb = w1_process_cb;
node->block = block;
node->m = (struct w1_netlink_msg *)((u8 *)&block->msg +
(size_t)((u8 *)m - (u8 *)msg));
node->sl = sl;
node->dev = dev;
if (sl && w1_reset_select_slave(sl)) { mutex_lock(&dev->list_mutex);
err = -ENODEV; list_add_tail(&node->async.async_entry, &dev->async_list);
goto out_up; wake_up_process(dev->thread);
} mutex_unlock(&dev->list_mutex);
++node;
while (mlen) {
cmd = (struct w1_netlink_cmd *)cmd_data;
if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
err = -E2BIG;
break;
}
if (sl)
err = w1_process_command_slave(sl, msg, m, cmd);
else
err = w1_process_command_master(dev, msg, m, cmd);
w1_netlink_send_error(msg, m, cmd, err);
err = 0;
cmd_data += cmd->len + sizeof(struct w1_netlink_cmd);
mlen -= cmd->len + sizeof(struct w1_netlink_cmd);
}
out_up:
atomic_dec(&dev->refcnt);
if (sl)
atomic_dec(&sl->refcnt);
mutex_unlock(&dev->mutex);
out_cont: out_cont:
if (!cmd || err) if (err)
w1_netlink_send_error(msg, m, cmd, err); w1_netlink_send_error(msg, m, NULL, err);
msg->len -= sizeof(struct w1_netlink_msg) + m->len; msg_len -= sizeof(struct w1_netlink_msg) + m->len;
m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len); m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len);
/* /*
...@@ -458,6 +548,8 @@ static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp) ...@@ -458,6 +548,8 @@ static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
if (err == -ENODEV) if (err == -ENODEV)
err = 0; err = 0;
} }
if (block && atomic_sub_return(1, &block->refcnt) == 0)
kfree(block);
} }
int w1_init_netlink(void) int w1_init_netlink(void)
......
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