From b7d885145538ddedb1ae23b782ab7c7c0a856e9f Mon Sep 17 00:00:00 2001 From: Tomas Winkler Date: Tue, 10 Feb 2015 10:39:31 +0200 Subject: [PATCH] mei: revamp me clients list handling 1. Use rw lock to access the me_clients list 2. Reuse already defined find functions also when removing particular me client 3. Add wrappers for addition and deletion Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman --- drivers/misc/mei/client.c | 194 +++++++++++++++++++++++++++++++++------------ drivers/misc/mei/client.h | 5 +- drivers/misc/mei/debugfs.c | 19 +++-- drivers/misc/mei/hbm.c | 3 +- drivers/misc/mei/init.c | 1 + drivers/misc/mei/mei_dev.h | 2 + 6 files changed, 162 insertions(+), 62 deletions(-) diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c index dfbddfe..48813c2 100644 --- a/drivers/misc/mei/client.c +++ b/drivers/misc/mei/client.c @@ -48,14 +48,14 @@ void mei_me_cl_init(struct mei_me_client *me_cl) */ struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl) { - if (me_cl) - kref_get(&me_cl->refcnt); + if (me_cl && kref_get_unless_zero(&me_cl->refcnt)) + return me_cl; - return me_cl; + return NULL; } /** - * mei_me_cl_release - unlink and free me client + * mei_me_cl_release - free me client * * Locking: called under "dev->device_lock" lock * @@ -65,9 +65,10 @@ static void mei_me_cl_release(struct kref *ref) { struct mei_me_client *me_cl = container_of(ref, struct mei_me_client, refcnt); - list_del(&me_cl->list); + kfree(me_cl); } + /** * mei_me_cl_put - decrease me client refcount and free client if necessary * @@ -82,51 +83,146 @@ void mei_me_cl_put(struct mei_me_client *me_cl) } /** - * mei_me_cl_by_uuid - locate me client by uuid + * __mei_me_cl_del - delete me client form the list and decrease + * reference counter + * + * @dev: mei device + * @me_cl: me client + * + * Locking: dev->me_clients_rwsem + */ +static void __mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl) +{ + if (!me_cl) + return; + + list_del(&me_cl->list); + mei_me_cl_put(me_cl); +} + +/** + * mei_me_cl_add - add me client to the list + * + * @dev: mei device + * @me_cl: me client + */ +void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl) +{ + down_write(&dev->me_clients_rwsem); + list_add(&me_cl->list, &dev->me_clients); + up_write(&dev->me_clients_rwsem); +} + +/** + * __mei_me_cl_by_uuid - locate me client by uuid * increases ref count * * @dev: mei device * @uuid: me client uuid * - * Locking: called under "dev->device_lock" lock - * * Return: me client or NULL if not found + * + * Locking: dev->me_clients_rwsem */ -struct mei_me_client *mei_me_cl_by_uuid(const struct mei_device *dev, +static struct mei_me_client *__mei_me_cl_by_uuid(struct mei_device *dev, const uuid_le *uuid) { struct mei_me_client *me_cl; + const uuid_le *pn; + + WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem)); - list_for_each_entry(me_cl, &dev->me_clients, list) - if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0) + list_for_each_entry(me_cl, &dev->me_clients, list) { + pn = &me_cl->props.protocol_name; + if (uuid_le_cmp(*uuid, *pn) == 0) return mei_me_cl_get(me_cl); + } return NULL; } /** + * mei_me_cl_by_uuid - locate me client by uuid + * increases ref count + * + * @dev: mei device + * @uuid: me client uuid + * + * Return: me client or NULL if not found + * + * Locking: dev->me_clients_rwsem + */ +struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev, + const uuid_le *uuid) +{ + struct mei_me_client *me_cl; + + down_read(&dev->me_clients_rwsem); + me_cl = __mei_me_cl_by_uuid(dev, uuid); + up_read(&dev->me_clients_rwsem); + + return me_cl; +} + +/** * mei_me_cl_by_id - locate me client by client id * increases ref count * * @dev: the device structure * @client_id: me client id * - * Locking: called under "dev->device_lock" lock - * * Return: me client or NULL if not found + * + * Locking: dev->me_clients_rwsem */ struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id) { + struct mei_me_client *__me_cl, *me_cl = NULL; + + down_read(&dev->me_clients_rwsem); + list_for_each_entry(__me_cl, &dev->me_clients, list) { + if (__me_cl->client_id == client_id) { + me_cl = mei_me_cl_get(__me_cl); + break; + } + } + up_read(&dev->me_clients_rwsem); + + return me_cl; +} + +/** + * __mei_me_cl_by_uuid_id - locate me client by client id and uuid + * increases ref count + * + * @dev: the device structure + * @uuid: me client uuid + * @client_id: me client id + * + * Return: me client or null if not found + * + * Locking: dev->me_clients_rwsem + */ +static struct mei_me_client *__mei_me_cl_by_uuid_id(struct mei_device *dev, + const uuid_le *uuid, u8 client_id) +{ struct mei_me_client *me_cl; + const uuid_le *pn; + + WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem)); - list_for_each_entry(me_cl, &dev->me_clients, list) - if (me_cl->client_id == client_id) + list_for_each_entry(me_cl, &dev->me_clients, list) { + pn = &me_cl->props.protocol_name; + if (uuid_le_cmp(*uuid, *pn) == 0 && + me_cl->client_id == client_id) return mei_me_cl_get(me_cl); + } return NULL; } + /** * mei_me_cl_by_uuid_id - locate me client by client id and uuid * increases ref count @@ -135,21 +231,18 @@ struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id) * @uuid: me client uuid * @client_id: me client id * - * Locking: called under "dev->device_lock" lock - * - * Return: me client or NULL if not found + * Return: me client or null if not found */ struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 client_id) { struct mei_me_client *me_cl; - list_for_each_entry(me_cl, &dev->me_clients, list) - if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0 && - me_cl->client_id == client_id) - return mei_me_cl_get(me_cl); + down_read(&dev->me_clients_rwsem); + me_cl = __mei_me_cl_by_uuid_id(dev, uuid, client_id); + up_read(&dev->me_clients_rwsem); - return NULL; + return me_cl; } /** @@ -162,12 +255,14 @@ struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev, */ void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid) { - struct mei_me_client *me_cl, *next; + struct mei_me_client *me_cl; dev_dbg(dev->dev, "remove %pUl\n", uuid); - list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) - if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0) - mei_me_cl_put(me_cl); + + down_write(&dev->me_clients_rwsem); + me_cl = __mei_me_cl_by_uuid(dev, uuid); + __mei_me_cl_del(dev, me_cl); + up_write(&dev->me_clients_rwsem); } /** @@ -181,15 +276,14 @@ void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid) */ void mei_me_cl_rm_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 id) { - struct mei_me_client *me_cl, *next; - const uuid_le *pn; + struct mei_me_client *me_cl; dev_dbg(dev->dev, "remove %pUl %d\n", uuid, id); - list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) { - pn = &me_cl->props.protocol_name; - if (me_cl->client_id == id && uuid_le_cmp(*uuid, *pn) == 0) - mei_me_cl_put(me_cl); - } + + down_write(&dev->me_clients_rwsem); + me_cl = __mei_me_cl_by_uuid_id(dev, uuid, id); + __mei_me_cl_del(dev, me_cl); + up_write(&dev->me_clients_rwsem); } /** @@ -203,12 +297,12 @@ void mei_me_cl_rm_all(struct mei_device *dev) { struct mei_me_client *me_cl, *next; + down_write(&dev->me_clients_rwsem); list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) - mei_me_cl_put(me_cl); + __mei_me_cl_del(dev, me_cl); + up_write(&dev->me_clients_rwsem); } - - /** * mei_cl_cmp_id - tells if the clients are the same * @@ -535,28 +629,28 @@ int mei_cl_unlink(struct mei_cl *cl) void mei_host_client_init(struct work_struct *work) { - struct mei_device *dev = container_of(work, - struct mei_device, init_work); + struct mei_device *dev = + container_of(work, struct mei_device, init_work); struct mei_me_client *me_cl; - struct mei_client_properties *props; mutex_lock(&dev->device_lock); - list_for_each_entry(me_cl, &dev->me_clients, list) { - props = &me_cl->props; - if (!uuid_le_cmp(props->protocol_name, mei_amthif_guid)) - mei_amthif_host_init(dev); - else if (!uuid_le_cmp(props->protocol_name, mei_wd_guid)) - mei_wd_host_init(dev); - else if (!uuid_le_cmp(props->protocol_name, mei_nfc_guid)) - mei_nfc_host_init(dev); + me_cl = mei_me_cl_by_uuid(dev, &mei_amthif_guid); + if (me_cl) + mei_amthif_host_init(dev); + + me_cl = mei_me_cl_by_uuid(dev, &mei_wd_guid); + if (me_cl) + mei_wd_host_init(dev); + + me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_guid); + if (me_cl) + mei_nfc_host_init(dev); - } dev->dev_state = MEI_DEV_ENABLED; dev->reset_count = 0; - mutex_unlock(&dev->device_lock); pm_runtime_mark_last_busy(dev->dev); diff --git a/drivers/misc/mei/client.h b/drivers/misc/mei/client.h index cfcde8e..80386f9 100644 --- a/drivers/misc/mei/client.h +++ b/drivers/misc/mei/client.h @@ -31,7 +31,10 @@ void mei_me_cl_init(struct mei_me_client *me_cl); void mei_me_cl_put(struct mei_me_client *me_cl); struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl); -struct mei_me_client *mei_me_cl_by_uuid(const struct mei_device *dev, +void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl); +void mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl); + +struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev, const uuid_le *uuid); struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id); struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev, diff --git a/drivers/misc/mei/debugfs.c b/drivers/misc/mei/debugfs.c index b125380..50fc663 100644 --- a/drivers/misc/mei/debugfs.c +++ b/drivers/misc/mei/debugfs.c @@ -28,7 +28,7 @@ static ssize_t mei_dbgfs_read_meclients(struct file *fp, char __user *ubuf, size_t cnt, loff_t *ppos) { struct mei_device *dev = fp->private_data; - struct mei_me_client *me_cl, *n; + struct mei_me_client *me_cl; size_t bufsz = 1; char *buf; int i = 0; @@ -38,15 +38,14 @@ static ssize_t mei_dbgfs_read_meclients(struct file *fp, char __user *ubuf, #define HDR \ " |id|fix| UUID |con|msg len|sb|refc|\n" - mutex_lock(&dev->device_lock); - + down_read(&dev->me_clients_rwsem); list_for_each_entry(me_cl, &dev->me_clients, list) bufsz++; bufsz *= sizeof(HDR) + 1; buf = kzalloc(bufsz, GFP_KERNEL); if (!buf) { - mutex_unlock(&dev->device_lock); + up_read(&dev->me_clients_rwsem); return -ENOMEM; } @@ -56,10 +55,9 @@ static ssize_t mei_dbgfs_read_meclients(struct file *fp, char __user *ubuf, if (dev->dev_state != MEI_DEV_ENABLED) goto out; - list_for_each_entry_safe(me_cl, n, &dev->me_clients, list) { + list_for_each_entry(me_cl, &dev->me_clients, list) { - me_cl = mei_me_cl_get(me_cl); - if (me_cl) { + if (mei_me_cl_get(me_cl)) { pos += scnprintf(buf + pos, bufsz - pos, "%2d|%2d|%3d|%pUl|%3d|%7d|%2d|%4d|\n", i++, me_cl->client_id, @@ -69,12 +67,13 @@ static ssize_t mei_dbgfs_read_meclients(struct file *fp, char __user *ubuf, me_cl->props.max_msg_length, me_cl->props.single_recv_buf, atomic_read(&me_cl->refcnt.refcount)); - } - mei_me_cl_put(me_cl); + mei_me_cl_put(me_cl); + } } + out: - mutex_unlock(&dev->device_lock); + up_read(&dev->me_clients_rwsem); ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, pos); kfree(buf); return ret; diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c index c8412d4..4f83e9a 100644 --- a/drivers/misc/mei/hbm.c +++ b/drivers/misc/mei/hbm.c @@ -338,7 +338,8 @@ static int mei_hbm_me_cl_add(struct mei_device *dev, me_cl->client_id = res->me_addr; me_cl->mei_flow_ctrl_creds = 0; - list_add(&me_cl->list, &dev->me_clients); + mei_me_cl_add(dev, me_cl); + return 0; } diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c index 9306219..106c054 100644 --- a/drivers/misc/mei/init.c +++ b/drivers/misc/mei/init.c @@ -387,6 +387,7 @@ void mei_device_init(struct mei_device *dev, INIT_LIST_HEAD(&dev->device_list); INIT_LIST_HEAD(&dev->me_clients); mutex_init(&dev->device_lock); + init_rwsem(&dev->me_clients_rwsem); init_waitqueue_head(&dev->wait_hw_ready); init_waitqueue_head(&dev->wait_pg); init_waitqueue_head(&dev->wait_hbm_start); diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h index 6c6ce93..102cc66 100644 --- a/drivers/misc/mei/mei_dev.h +++ b/drivers/misc/mei/mei_dev.h @@ -460,6 +460,7 @@ const char *mei_pg_state_str(enum mei_pg_state state); * @version : HBM protocol version in use * @hbm_f_pg_supported : hbm feature pgi protocol * + * @me_clients_rwsem: rw lock over me_clients list * @me_clients : list of FW clients * @me_clients_map : FW clients bit map * @host_clients_map : host clients id pool @@ -556,6 +557,7 @@ struct mei_device { struct hbm_version version; unsigned int hbm_f_pg_supported:1; + struct rw_semaphore me_clients_rwsem; struct list_head me_clients; DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX); DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX); -- 2.7.4