[PATCH] tpm: use find_first_zero_bit

From: Kylene Jo Hall
Date: Wed Apr 12 2006 - 17:47:20 EST


On Tue, 2006-04-11 at 16:02 -0700, Andrew Morton wrote:
> - }
> + /* This should use find_first_zero_bit() */
> + for (dev_num = 0; dev_num < TPM_NUM_DEVICES; dev_num++) {

Given the suggestion in the code of your use-clear_bit-fix. This patch
uses find_first_zero_bit to find a bit instead of the roll my own for
loop solution.

Signed-off-by: Kylie Hall <kjhall@xxxxxxxxxx>
---
drivers/char/tpm/tpm.c | 20 ++++++--------------
1 files changed, 6 insertions(+), 14 deletions(-)

--- linux-2.6.17-rc1-mm2/drivers/char/tpm/tpm.c 2006-04-12 11:46:18.375300250 -0500
+++ linux-2.6.17-rc1/drivers/char/tpm/tpm.c 2006-04-12 12:34:41.692746250 -0500
@@ -1090,7 +1090,6 @@ struct tpm_chip *tpm_register_hardware(s

char *devname;
struct tpm_chip *chip;
- int dev_num;

/* Driver specific per-device data */
chip = kzalloc(sizeof(*chip), GFP_KERNEL);
@@ -1109,18 +1108,9 @@ struct tpm_chip *tpm_register_hardware(s

memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));

- chip->dev_num = -1;
-
- /* This should use find_first_zero_bit() */
- for (dev_num = 0; dev_num < TPM_NUM_DEVICES; dev_num++) {
- if (!test_bit(dev_num, dev_mask)) {
- chip->dev_num = dev_num;
- set_bit(dev_num, dev_mask);
- break;
- }
- }
-
- if (chip->dev_num < 0) {
+ chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
+
+ if (chip->dev_num < 0 || chip->dev_num > TPM_NUM_DEVICES) {
dev_err(dev, "No available tpm device numbers\n");
kfree(chip);
return NULL;
@@ -1129,6 +1119,8 @@ struct tpm_chip *tpm_register_hardware(s
else
chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;

+ set_bit(chip->dev_num, dev_mask);
+
devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
chip->vendor.miscdev.name = devname;
@@ -1143,7 +1135,7 @@ struct tpm_chip *tpm_register_hardware(s
chip->vendor.miscdev.minor);
put_device(dev);
kfree(chip);
- clear_bit(dev_num, dev_mask);
+ clear_bit(chip->dev_num, dev_mask);
return NULL;
}



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/