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Merge branch 'tpmdd-next-v3.6' of git://github.com/shpedoikal/linux into for-linus

This commit is contained in:
James Morris 2012-10-11 18:41:29 +08:00
parent bb95a0d73b abce9ac292
commit 59b69ac2ba
1 changed files with 14 additions and 7 deletions
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21
drivers/char/tpm/tpm.c
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@ -1182,17 +1182,20 @@ ssize_t tpm_write(struct file *file, const char __user *buf,
size_t size, loff_t *off)
{
struct tpm_chip *chip = file->private_data;
size_t in_size = size, out_size;
size_t in_size = size;
ssize_t out_size;
/* cannot perform a write until the read has cleared
either via tpm_read or a user_read_timer timeout */
while (atomic_read(&chip->data_pending) != 0)
msleep(TPM_TIMEOUT);
mutex_lock(&chip->buffer_mutex);
either via tpm_read or a user_read_timer timeout.
This also prevents splitted buffered writes from blocking here.
*/
if (atomic_read(&chip->data_pending) != 0)
return -EBUSY;
if (in_size > TPM_BUFSIZE)
in_size = TPM_BUFSIZE;
return -E2BIG;
mutex_lock(&chip->buffer_mutex);
if (copy_from_user
(chip->data_buffer, (void __user *) buf, in_size)) {
@ -1202,6 +1205,10 @@ ssize_t tpm_write(struct file *file, const char __user *buf,
/* atomic tpm command send and result receive */
out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
if (out_size < 0) {
mutex_unlock(&chip->buffer_mutex);
return out_size;
}
atomic_set(&chip->data_pending, out_size);
mutex_unlock(&chip->buffer_mutex);