diff options
Diffstat (limited to 'compat/backport-3.17.c')
| -rw-r--r-- | compat/backport-3.17.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/compat/backport-3.17.c b/compat/backport-3.17.c new file mode 100644 index 0000000..bf6027c --- /dev/null +++ b/compat/backport-3.17.c @@ -0,0 +1,166 @@ +/* + * Copyright (c) 2014 Hauke Mehrtens <hauke@hauke-m.de> + * + * Backport functionality introduced in Linux 3.17. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/wait.h> +#include <linux/sched.h> +#include <linux/device.h> +#include <linux/export.h> +#include <linux/ktime.h> +#include <linux/jiffies.h> +#include <linux/moduleparam.h> + +int bit_wait(void *word) +{ + schedule(); + return 0; +} +EXPORT_SYMBOL_GPL(bit_wait); + +int bit_wait_io(void *word) +{ + io_schedule(); + return 0; +} +EXPORT_SYMBOL_GPL(bit_wait_io); + +/** + * ktime_get_raw - Returns the raw monotonic time in ktime_t format + */ +ktime_t ktime_get_raw(void) +{ + struct timespec ts; + + getrawmonotonic(&ts); + return timespec_to_ktime(ts); +} +EXPORT_SYMBOL_GPL(ktime_get_raw); + + +/** + * nsecs_to_jiffies64 - Convert nsecs in u64 to jiffies64 + * + * @n: nsecs in u64 + * + * Unlike {m,u}secs_to_jiffies, type of input is not unsigned int but u64. + * And this doesn't return MAX_JIFFY_OFFSET since this function is designed + * for scheduler, not for use in device drivers to calculate timeout value. + * + * note: + * NSEC_PER_SEC = 10^9 = (5^9 * 2^9) = (1953125 * 512) + * ULLONG_MAX ns = 18446744073.709551615 secs = about 584 years + */ +static u64 backport_nsecs_to_jiffies64(u64 n) +{ +#if (NSEC_PER_SEC % HZ) == 0 + /* Common case, HZ = 100, 128, 200, 250, 256, 500, 512, 1000 etc. */ + return div_u64(n, NSEC_PER_SEC / HZ); +#elif (HZ % 512) == 0 + /* overflow after 292 years if HZ = 1024 */ + return div_u64(n * HZ / 512, NSEC_PER_SEC / 512); +#else + /* + * Generic case - optimized for cases where HZ is a multiple of 3. + * overflow after 64.99 years, exact for HZ = 60, 72, 90, 120 etc. + */ + return div_u64(n * 9, (9ull * NSEC_PER_SEC + HZ / 2) / HZ); +#endif +} + +/** + * nsecs_to_jiffies - Convert nsecs in u64 to jiffies + * + * @n: nsecs in u64 + * + * Unlike {m,u}secs_to_jiffies, type of input is not unsigned int but u64. + * And this doesn't return MAX_JIFFY_OFFSET since this function is designed + * for scheduler, not for use in device drivers to calculate timeout value. + * + * note: + * NSEC_PER_SEC = 10^9 = (5^9 * 2^9) = (1953125 * 512) + * ULLONG_MAX ns = 18446744073.709551615 secs = about 584 years + */ +unsigned long nsecs_to_jiffies(u64 n) +{ + return (unsigned long)backport_nsecs_to_jiffies64(n); +} +EXPORT_SYMBOL_GPL(nsecs_to_jiffies); + +/** + * devm_kvasprintf - Allocate resource managed space + * for the formatted string. + * @dev: Device to allocate memory for + * @gfp: the GFP mask used in the devm_kmalloc() call when + * allocating memory + * @fmt: the formatted string to duplicate + * @ap: the list of tokens to be placed in the formatted string + * RETURNS: + * Pointer to allocated string on success, NULL on failure. + */ +char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt, + va_list ap) +{ + unsigned int len; + char *p; + va_list aq; + + va_copy(aq, ap); + len = vsnprintf(NULL, 0, fmt, aq); + va_end(aq); + + p = devm_kmalloc(dev, len+1, gfp); + if (!p) + return NULL; + + vsnprintf(p, len+1, fmt, ap); + + return p; +} +EXPORT_SYMBOL_GPL(devm_kvasprintf); + +/** + * devm_kasprintf - Allocate resource managed space + * and copy an existing formatted string into that + * @dev: Device to allocate memory for + * @gfp: the GFP mask used in the devm_kmalloc() call when + * allocating memory + * @fmt: the string to duplicate + * RETURNS: + * Pointer to allocated string on success, NULL on failure. + */ +char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...) +{ + va_list ap; + char *p; + + va_start(ap, fmt); + p = devm_kvasprintf(dev, gfp, fmt, ap); + va_end(ap); + + return p; +} +EXPORT_SYMBOL_GPL(devm_kasprintf); + +#define STANDARD_PARAM_DEF(name, type, format, strtolfn) \ + int param_set_##name(const char *val, const struct kernel_param *kp) \ + { \ + return strtolfn(val, 0, (type *)kp->arg); \ + } \ + int param_get_##name(char *buffer, const struct kernel_param *kp) \ + { \ + return scnprintf(buffer, PAGE_SIZE, format, \ + *((type *)kp->arg)); \ + } \ + struct kernel_param_ops param_ops_##name = { \ + .set = param_set_##name, \ + .get = param_get_##name, \ + }; \ + EXPORT_SYMBOL(param_set_##name); \ + EXPORT_SYMBOL(param_get_##name); \ + EXPORT_SYMBOL(param_ops_##name) +STANDARD_PARAM_DEF(ullong, unsigned long long, "%llu", kstrtoull); |