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| author |   Dongxiao Xu <dongxiao.xu@intel.com> | 2009-05-31 14:43:42 +0800 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@suse.de> | 2009-06-19 11:00:55 -0700 |
| commit | 72abd2288318a35fbf225b93a31d4623e3b8c872 (patch) | |
| tree | 9ce193ab0c02b57cb2ef59009d4aafd98c3176df /drivers/staging | |
| parent | Staging: heci: fix wrong order of device_lock and file_lock (diff) | |
| download | linux-dev-72abd2288318a35fbf225b93a31d4623e3b8c872.tar.xz linux-dev-72abd2288318a35fbf225b93a31d4623e3b8c872.zip | |
Staging: heci: fix spinlock order mess of device_lock and read_io_lock
In orginal code, the device_lock and read_io_lock is mess order when nested,
which may bring dead lock. This patch unify the spinlock order of device_lock
and read_io_lock. First acquire device_lock, then read_io_lock.
Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/staging')
| -rw-r--r-- | drivers/staging/heci/heci_main.c | 2 | ||||
| -rw-r--r-- | drivers/staging/heci/io_heci.c | 17 |
2 files changed, 16 insertions, 3 deletions
diff --git a/drivers/staging/heci/heci_main.c b/drivers/staging/heci/heci_main.c index daf1107cb8e0..fb97428b457c 100644 --- a/drivers/staging/heci/heci_main.c +++ b/drivers/staging/heci/heci_main.c @@ -954,8 +954,8 @@ static ssize_t heci_read(struct file *file, char __user *ubuf, goto out; } - spin_lock(&file_ext->read_io_lock); err = heci_start_read(dev, if_num, file_ext); + spin_lock(&file_ext->read_io_lock); if (err != 0 && err != -EBUSY) { DBG("heci start read failure with status = %d\n", err); spin_unlock(&file_ext->read_io_lock); diff --git a/drivers/staging/heci/io_heci.c b/drivers/staging/heci/io_heci.c index 53dc770727d8..16c723566f6e 100644 --- a/drivers/staging/heci/io_heci.c +++ b/drivers/staging/heci/io_heci.c @@ -637,8 +637,9 @@ int heci_start_read(struct iamt_heci_device *dev, int if_num, DBG("received wrong function input param.\n"); return -ENODEV; } - if (file_ext->state != HECI_FILE_CONNECTED) + if (file_ext->state != HECI_FILE_CONNECTED) { return -ENODEV; + } spin_lock_bh(&dev->device_lock); if (dev->heci_state != HECI_ENABLED) { @@ -647,18 +648,26 @@ int heci_start_read(struct iamt_heci_device *dev, int if_num, } spin_unlock_bh(&dev->device_lock); DBG("check if read is pending.\n"); + spin_lock(&file_ext->read_io_lock); if ((file_ext->read_pending) || (file_ext->read_cb != NULL)) { DBG("read is pending.\n"); + spin_unlock(&file_ext->read_io_lock); return -EBUSY; } + spin_unlock(&file_ext->read_io_lock); + priv_cb = kzalloc(sizeof(struct heci_cb_private), GFP_KERNEL); if (!priv_cb) return -ENOMEM; + spin_lock(&file_ext->read_io_lock); DBG("allocation call back success\n" "host client = %d, ME client = %d\n", file_ext->host_client_id, file_ext->me_client_id); + spin_unlock(&file_ext->read_io_lock); + spin_lock_bh(&dev->device_lock); + spin_lock(&file_ext->read_io_lock); for (i = 0; i < dev->num_heci_me_clients; i++) { if (dev->me_clients[i].client_id == file_ext->me_client_id) break; @@ -666,6 +675,7 @@ int heci_start_read(struct iamt_heci_device *dev, int if_num, } BUG_ON(dev->me_clients[i].client_id != file_ext->me_client_id); + spin_unlock(&file_ext->read_io_lock); if (i == dev->num_heci_me_clients) { rets = -ENODEV; goto unlock; @@ -684,12 +694,14 @@ int heci_start_read(struct iamt_heci_device *dev, int if_num, /* make sure information is zero before we start */ priv_cb->information = 0; priv_cb->file_private = (void *) file_ext; - file_ext->read_cb = priv_cb; spin_lock_bh(&dev->device_lock); + spin_lock(&file_ext->read_io_lock); + file_ext->read_cb = priv_cb; if (dev->host_buffer_is_empty) { dev->host_buffer_is_empty = 0; if (!heci_send_flow_control(dev, file_ext)) { rets = -ENODEV; + spin_unlock(&file_ext->read_io_lock); goto unlock; } else { list_add_tail(&priv_cb->cb_list, @@ -699,6 +711,7 @@ int heci_start_read(struct iamt_heci_device *dev, int if_num, list_add_tail(&priv_cb->cb_list, &dev->ctrl_wr_list.heci_cb.cb_list); } + spin_unlock(&file_ext->read_io_lock); spin_unlock_bh(&dev->device_lock); return rets; unlock: |