diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/tpm/tpm-dev-common.c | 141 | ||||
| -rw-r--r-- | drivers/char/tpm/tpm-dev.c | 1 | ||||
| -rw-r--r-- | drivers/char/tpm/tpm-dev.h | 13 | ||||
| -rw-r--r-- | drivers/char/tpm/tpm-interface.c | 24 | ||||
| -rw-r--r-- | drivers/char/tpm/tpm.h | 2 | ||||
| -rw-r--r-- | drivers/char/tpm/tpmrm-dev.c | 1 |
6 files changed, 137 insertions, 45 deletions
diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c index f0c033b69b62..99b5133a9d05 100644 --- a/drivers/char/tpm/tpm-dev-common.c +++ b/drivers/char/tpm/tpm-dev-common.c @@ -17,11 +17,36 @@ * License. * */ +#include <linux/poll.h> #include <linux/slab.h> #include <linux/uaccess.h> +#include <linux/workqueue.h> #include "tpm.h" #include "tpm-dev.h" +static struct workqueue_struct *tpm_dev_wq; +static DEFINE_MUTEX(tpm_dev_wq_lock); + +static void tpm_async_work(struct work_struct *work) +{ + struct file_priv *priv = + container_of(work, struct file_priv, async_work); + ssize_t ret; + + mutex_lock(&priv->buffer_mutex); + priv->command_enqueued = false; + ret = tpm_transmit(priv->chip, priv->space, priv->data_buffer, + sizeof(priv->data_buffer), 0); + + tpm_put_ops(priv->chip); + if (ret > 0) { + priv->data_pending = ret; + mod_timer(&priv->user_read_timer, jiffies + (120 * HZ)); + } + mutex_unlock(&priv->buffer_mutex); + wake_up_interruptible(&priv->async_wait); +} + static void user_reader_timeout(struct timer_list *t) { struct file_priv *priv = from_timer(priv, t, user_read_timer); @@ -29,17 +54,19 @@ static void user_reader_timeout(struct timer_list *t) pr_warn("TPM user space timeout is deprecated (pid=%d)\n", task_tgid_nr(current)); - schedule_work(&priv->work); + schedule_work(&priv->timeout_work); } -static void timeout_work(struct work_struct *work) +static void tpm_timeout_work(struct work_struct *work) { - struct file_priv *priv = container_of(work, struct file_priv, work); + struct file_priv *priv = container_of(work, struct file_priv, + timeout_work); mutex_lock(&priv->buffer_mutex); priv->data_pending = 0; memset(priv->data_buffer, 0, sizeof(priv->data_buffer)); mutex_unlock(&priv->buffer_mutex); + wake_up_interruptible(&priv->async_wait); } void tpm_common_open(struct file *file, struct tpm_chip *chip, @@ -50,8 +77,9 @@ void tpm_common_open(struct file *file, struct tpm_chip *chip, mutex_init(&priv->buffer_mutex); timer_setup(&priv->user_read_timer, user_reader_timeout, 0); - INIT_WORK(&priv->work, timeout_work); - + INIT_WORK(&priv->timeout_work, tpm_timeout_work); + INIT_WORK(&priv->async_work, tpm_async_work); + init_waitqueue_head(&priv->async_wait); file->private_data = priv; } @@ -63,15 +91,17 @@ ssize_t tpm_common_read(struct file *file, char __user *buf, int rc; del_singleshot_timer_sync(&priv->user_read_timer); - flush_work(&priv->work); + flush_work(&priv->timeout_work); mutex_lock(&priv->buffer_mutex); if (priv->data_pending) { ret_size = min_t(ssize_t, size, priv->data_pending); - rc = copy_to_user(buf, priv->data_buffer, ret_size); - memset(priv->data_buffer, 0, priv->data_pending); - if (rc) - ret_size = -EFAULT; + if (ret_size > 0) { + rc = copy_to_user(buf, priv->data_buffer, ret_size); + memset(priv->data_buffer, 0, priv->data_pending); + if (rc) + ret_size = -EFAULT; + } priv->data_pending = 0; } @@ -84,10 +114,9 @@ ssize_t tpm_common_write(struct file *file, const char __user *buf, size_t size, loff_t *off) { struct file_priv *priv = file->private_data; - size_t in_size = size; - ssize_t out_size; + int ret = 0; - if (in_size > TPM_BUFSIZE) + if (size > TPM_BUFSIZE) return -E2BIG; mutex_lock(&priv->buffer_mutex); @@ -96,21 +125,20 @@ ssize_t tpm_common_write(struct file *file, const char __user *buf, * tpm_read or a user_read_timer timeout. This also prevents split * buffered writes from blocking here. */ - if (priv->data_pending != 0) { - mutex_unlock(&priv->buffer_mutex); - return -EBUSY; + if (priv->data_pending != 0 || priv->command_enqueued) { + ret = -EBUSY; + goto out; } - if (copy_from_user - (priv->data_buffer, (void __user *) buf, in_size)) { - mutex_unlock(&priv->buffer_mutex); - return -EFAULT; + if (copy_from_user(priv->data_buffer, buf, size)) { + ret = -EFAULT; + goto out; } - if (in_size < 6 || - in_size < be32_to_cpu(*((__be32 *) (priv->data_buffer + 2)))) { - mutex_unlock(&priv->buffer_mutex); - return -EINVAL; + if (size < 6 || + size < be32_to_cpu(*((__be32 *)(priv->data_buffer + 2)))) { + ret = -EINVAL; + goto out; } /* atomic tpm command send and result receive. We only hold the ops @@ -118,25 +146,50 @@ ssize_t tpm_common_write(struct file *file, const char __user *buf, * the char dev is held open. */ if (tpm_try_get_ops(priv->chip)) { - mutex_unlock(&priv->buffer_mutex); - return -EPIPE; + ret = -EPIPE; + goto out; } - out_size = tpm_transmit(priv->chip, priv->space, priv->data_buffer, - sizeof(priv->data_buffer), 0); - tpm_put_ops(priv->chip); - if (out_size < 0) { + /* + * If in nonblocking mode schedule an async job to send + * the command return the size. + * In case of error the err code will be returned in + * the subsequent read call. + */ + if (file->f_flags & O_NONBLOCK) { + priv->command_enqueued = true; + queue_work(tpm_dev_wq, &priv->async_work); mutex_unlock(&priv->buffer_mutex); - return out_size; + return size; } - priv->data_pending = out_size; + ret = tpm_transmit(priv->chip, priv->space, priv->data_buffer, + sizeof(priv->data_buffer), 0); + tpm_put_ops(priv->chip); + + if (ret > 0) { + priv->data_pending = ret; + mod_timer(&priv->user_read_timer, jiffies + (120 * HZ)); + ret = size; + } +out: mutex_unlock(&priv->buffer_mutex); + return ret; +} + +__poll_t tpm_common_poll(struct file *file, poll_table *wait) +{ + struct file_priv *priv = file->private_data; + __poll_t mask = 0; + + poll_wait(file, &priv->async_wait, wait); - /* Set a timeout by which the reader must come claim the result */ - mod_timer(&priv->user_read_timer, jiffies + (120 * HZ)); + if (priv->data_pending) + mask = EPOLLIN | EPOLLRDNORM; + else + mask = EPOLLOUT | EPOLLWRNORM; - return in_size; + return mask; } /* @@ -144,8 +197,24 @@ ssize_t tpm_common_write(struct file *file, const char __user *buf, */ void tpm_common_release(struct file *file, struct file_priv *priv) { + flush_work(&priv->async_work); del_singleshot_timer_sync(&priv->user_read_timer); - flush_work(&priv->work); + flush_work(&priv->timeout_work); file->private_data = NULL; priv->data_pending = 0; } + +int __init tpm_dev_common_init(void) +{ + tpm_dev_wq = alloc_workqueue("tpm_dev_wq", WQ_MEM_RECLAIM, 0); + + return !tpm_dev_wq ? -ENOMEM : 0; +} + +void __exit tpm_dev_common_exit(void) +{ + if (tpm_dev_wq) { + destroy_workqueue(tpm_dev_wq); + tpm_dev_wq = NULL; + } +} diff --git a/drivers/char/tpm/tpm-dev.c b/drivers/char/tpm/tpm-dev.c index 98b9630c3a36..32f9738f1cb2 100644 --- a/drivers/char/tpm/tpm-dev.c +++ b/drivers/char/tpm/tpm-dev.c @@ -68,5 +68,6 @@ const struct file_operations tpm_fops = { .open = tpm_open, .read = tpm_common_read, .write = tpm_common_write, + .poll = tpm_common_poll, .release = tpm_release, }; diff --git a/drivers/char/tpm/tpm-dev.h b/drivers/char/tpm/tpm-dev.h index 4048677bbd78..a126b575cb8c 100644 --- a/drivers/char/tpm/tpm-dev.h +++ b/drivers/char/tpm/tpm-dev.h @@ -2,18 +2,22 @@ #ifndef _TPM_DEV_H #define _TPM_DEV_H +#include <linux/poll.h> #include "tpm.h" struct file_priv { struct tpm_chip *chip; struct tpm_space *space; - /* Data passed to and from the tpm via the read/write calls */ - size_t data_pending; + /* Holds the amount of data passed or an error code from async op */ + ssize_t data_pending; struct mutex buffer_mutex; struct timer_list user_read_timer; /* user needs to claim result */ - struct work_struct work; + struct work_struct timeout_work; + struct work_struct async_work; + wait_queue_head_t async_wait; + bool command_enqueued; u8 data_buffer[TPM_BUFSIZE]; }; @@ -24,6 +28,7 @@ ssize_t tpm_common_read(struct file *file, char __user *buf, size_t size, loff_t *off); ssize_t tpm_common_write(struct file *file, const char __user *buf, size_t size, loff_t *off); -void tpm_common_release(struct file *file, struct file_priv *priv); +__poll_t tpm_common_poll(struct file *file, poll_table *wait); +void tpm_common_release(struct file *file, struct file_priv *priv); #endif diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 7d958ff426e0..129f640424b7 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -1409,19 +1409,32 @@ static int __init tpm_init(void) tpmrm_class = class_create(THIS_MODULE, "tpmrm"); if (IS_ERR(tpmrm_class)) { pr_err("couldn't create tpmrm class\n"); - class_destroy(tpm_class); - return PTR_ERR(tpmrm_class); + rc = PTR_ERR(tpmrm_class); + goto out_destroy_tpm_class; } rc = alloc_chrdev_region(&tpm_devt, 0, 2*TPM_NUM_DEVICES, "tpm"); if (rc < 0) { pr_err("tpm: failed to allocate char dev region\n"); - class_destroy(tpmrm_class); - class_destroy(tpm_class); - return rc; + goto out_destroy_tpmrm_class; + } + + rc = tpm_dev_common_init(); + if (rc) { + pr_err("tpm: failed to allocate char dev region\n"); + goto out_unreg_chrdev; } return 0; + +out_unreg_chrdev: + unregister_chrdev_region(tpm_devt, 2 * TPM_NUM_DEVICES); +out_destroy_tpmrm_class: + class_destroy(tpmrm_class); +out_destroy_tpm_class: + class_destroy(tpm_class); + + return rc; } static void __exit tpm_exit(void) @@ -1430,6 +1443,7 @@ static void __exit tpm_exit(void) class_destroy(tpm_class); class_destroy(tpmrm_class); unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES); + tpm_dev_common_exit(); } subsys_initcall(tpm_init); diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index f3501d05264f..f20dc8ece348 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -604,4 +604,6 @@ int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, int tpm_bios_log_setup(struct tpm_chip *chip); void tpm_bios_log_teardown(struct tpm_chip *chip); +int tpm_dev_common_init(void); +void tpm_dev_common_exit(void); #endif diff --git a/drivers/char/tpm/tpmrm-dev.c b/drivers/char/tpm/tpmrm-dev.c index 96006c6b9696..0c751a79bbed 100644 --- a/drivers/char/tpm/tpmrm-dev.c +++ b/drivers/char/tpm/tpmrm-dev.c @@ -51,5 +51,6 @@ const struct file_operations tpmrm_fops = { .open = tpmrm_open, .read = tpm_common_read, .write = tpm_common_write, + .poll = tpm_common_poll, .release = tpmrm_release, }; |