Y2038

y2038@lists.linaro.org

1 participants
1134 discussions

[PATCH v5 04/24] time: Introduce do_sys_settimeofday64()

by Baolin Wang

Due to the do_sys_settimeofday() with timespec type is not year 2038 safe on 32bit systems, and it should introduce the do_sys_settimeofday64() function with timespec64 type to make it is ready for 2038 issue. For removing the old do_sys_settimeofday() function with timespec type conveniently in future, it should move the do_sys_settimeofday() function to the timekeeping.h file as a 'static inline' helper that just calls do_sys_settimeofday64(). Signed-off-by: Baolin Wang <baolin.wang(a)linaro.org> --- include/linux/timekeeping.h | 11 +++++++++-- kernel/time/time.c | 8 ++++---- 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index f886bdb..2dcc86b 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -11,8 +11,15 @@ extern int timekeeping_suspended; */ extern void do_gettimeofday(struct timeval *tv); extern int do_settimeofday64(const struct timespec64 *ts); -extern int do_sys_settimeofday(const struct timespec *tv, - const struct timezone *tz); +extern int do_sys_settimeofday64(const struct timespec64 *tv, + const struct timezone *tz); +static inline int do_sys_settimeofday(const struct timespec *tv, + const struct timezone *tz) +{ + struct timespec64 ts64 = timespec_to_timespec64(*tv); + + return do_sys_settimeofday64(&ts64, tz); +} /* * Kernel time accessors diff --git a/kernel/time/time.c b/kernel/time/time.c index 972e3bb..5aefe2d 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -160,15 +160,15 @@ static inline void warp_clock(void) * various programs will get confused when the clock gets warped. */ -int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz) +int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz) { static int firsttime = 1; int error = 0; - if (tv && !timespec_valid(tv)) + if (tv && !timespec64_valid(tv)) return -EINVAL; - error = security_settime(tv, tz); + error = security_settime64(tv, tz); if (error) return error; @@ -186,7 +186,7 @@ int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz) } } if (tv) - return do_settimeofday(tv); + return do_settimeofday64(tv); return 0; } -- 1.7.9.5

10 years

[PATCH v5 03/24] security: Introduce security_settime64()

by Baolin Wang

Due to the security_settime() with timespec type is not year 2038 safe on 32bit systems. Introduce the security_settime64() function with timespec64 type. Change the settime() callback of security_list_options structure argument with timespec64 type as a helper function wrapped by security_settime64(). The cap_settime() as a helper function is only called by security_settime64() and security_settime() functions, and it need change the argument with timespec64 type. Signed-off-by: Baolin Wang <baolin.wang(a)linaro.org> --- include/linux/lsm_hooks.h | 5 +++-- include/linux/security.h | 20 +++++++++++++++++--- security/commoncap.c | 2 +- security/security.c | 2 +- 4 files changed, 22 insertions(+), 7 deletions(-) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 9429f05..d791f35 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -1191,7 +1191,8 @@ * Return 0 if permission is granted. * @settime: * Check permission to change the system time. - * struct timespec and timezone are defined in include/linux/time.h + * struct timespec64 is defined in include/linux/time64.h and timezone + * is defined in include/linux/time.h * @ts contains new time * @tz contains new timezone * Return 0 if permission is granted. @@ -1324,7 +1325,7 @@ union security_list_options { int (*quotactl)(int cmds, int type, int id, struct super_block *sb); int (*quota_on)(struct dentry *dentry); int (*syslog)(int type); - int (*settime)(const struct timespec *ts, const struct timezone *tz); + int (*settime)(const struct timespec64 *ts, const struct timezone *tz); int (*vm_enough_memory)(struct mm_struct *mm, long pages); int (*bprm_set_creds)(struct linux_binprm *bprm); diff --git a/include/linux/security.h b/include/linux/security.h index 79d85dd..520f903 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -69,7 +69,7 @@ struct timezone; /* These functions are in security/commoncap.c */ extern int cap_capable(const struct cred *cred, struct user_namespace *ns, int cap, int audit); -extern int cap_settime(const struct timespec *ts, const struct timezone *tz); +extern int cap_settime(const struct timespec64 *ts, const struct timezone *tz); extern int cap_ptrace_access_check(struct task_struct *child, unsigned int mode); extern int cap_ptrace_traceme(struct task_struct *parent); extern int cap_capget(struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted); @@ -206,7 +206,13 @@ int security_capable_noaudit(const struct cred *cred, struct user_namespace *ns, int security_quotactl(int cmds, int type, int id, struct super_block *sb); int security_quota_on(struct dentry *dentry); int security_syslog(int type); -int security_settime(const struct timespec *ts, const struct timezone *tz); +int security_settime64(const struct timespec64 *ts, const struct timezone *tz); +static int security_settime(const struct timespec *ts, const struct timezone *tz) +{ + struct timespec64 ts64 = timespec_to_timespec64(*ts); + + return security_settime64(&ts64, tz); +} int security_vm_enough_memory_mm(struct mm_struct *mm, long pages); int security_bprm_set_creds(struct linux_binprm *bprm); int security_bprm_check(struct linux_binprm *bprm); @@ -457,10 +463,18 @@ static inline int security_syslog(int type) return 0; } +static inline int security_settime64(const struct timespec64 *ts, + const struct timezone *tz) +{ + return cap_settime(ts, tz); +} + static inline int security_settime(const struct timespec *ts, const struct timezone *tz) { - return cap_settime(ts, tz); + struct timsepc64 ts64 = timespec_to_timespec64(*ts); + + return cap_settime(&ts64, tz); } static inline int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) diff --git a/security/commoncap.c b/security/commoncap.c index d103f5a4..17b1f79 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -111,7 +111,7 @@ int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, * Determine whether the current process may set the system clock and timezone * information, returning 0 if permission granted, -ve if denied. */ -int cap_settime(const struct timespec *ts, const struct timezone *tz) +int cap_settime(const struct timespec64 *ts, const struct timezone *tz) { if (!capable(CAP_SYS_TIME)) return -EPERM; diff --git a/security/security.c b/security/security.c index 595fffa..8d0dbd6 100644 --- a/security/security.c +++ b/security/security.c @@ -213,7 +213,7 @@ int security_syslog(int type) return call_int_hook(syslog, 0, type); } -int security_settime(const struct timespec *ts, const struct timezone *tz) +int security_settime64(const struct timespec64 *ts, const struct timezone *tz) { return call_int_hook(settime, 0, ts, tz); } -- 1.7.9.5

10 years

[PATCH v5 02/24] timekeeping: Introduce current_kernel_time64()

by Baolin Wang

The current_kernel_time() is not year 2038 safe on 32bit systems due to return timespec value. Introduce current_kernel_time64() function which returns timespec64 value, also as a helper function calling by current_kernel_time(). Signed-off-by: Baolin Wang <baolin.wang(a)linaro.org> --- include/linux/timekeeping.h | 10 +++++++++- kernel/time/timekeeping.c | 6 +++--- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 3aa72e6..f886bdb 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -18,10 +18,18 @@ extern int do_sys_settimeofday(const struct timespec *tv, * Kernel time accessors */ unsigned long get_seconds(void); -struct timespec current_kernel_time(void); +struct timespec64 current_kernel_time64(void); /* does not take xtime_lock */ struct timespec __current_kernel_time(void); +static inline struct timespec current_kernel_time(void) +{ + struct timespec64 now = current_kernel_time64(); + + return timespec64_to_timespec(now); +} + /* * timespec based interfaces */ diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 0d784b3..5fe9b77 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1857,7 +1857,7 @@ struct timespec __current_kernel_time(void) return timespec64_to_timespec(tk_xtime(tk)); } -struct timespec current_kernel_time(void) +struct timespec64 current_kernel_time64(void) { struct timekeeper *tk = &tk_core.timekeeper; struct timespec64 now; @@ -1869,9 +1869,9 @@ struct timespec current_kernel_time(void) now = tk_xtime(tk); } while (read_seqcount_retry(&tk_core.seq, seq)); - return timespec64_to_timespec(now); + return now; } -EXPORT_SYMBOL(current_kernel_time); +EXPORT_SYMBOL(current_kernel_time64); struct timespec64 get_monotonic_coarse64(void) { -- 1.7.9.5

10 years

[PATCH v5 01/24] time: Introduce struct itimerspec64

by Baolin Wang

The itimerspec is not year 2038 safe on 32bit systems due to the limitation of the struct timespec members. Introduce itimerspec64 which uses struct timespec64 instead and provide conversion functions. Signed-off-by: Baolin Wang <baolin.wang(a)linaro.org> --- include/linux/time64.h | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/include/linux/time64.h b/include/linux/time64.h index 12d4e82..132062b 100644 --- a/include/linux/time64.h +++ b/include/linux/time64.h @@ -12,11 +12,18 @@ typedef __s64 time64_t; */ #if __BITS_PER_LONG == 64 # define timespec64 timespec +#define itimerspec64 itimerspec #else struct timespec64 { time64_t tv_sec; /* seconds */ long tv_nsec; /* nanoseconds */ }; + +struct itimerspec64 { + struct timespec64 it_interval; + struct timespec64 it_value; +}; + #endif /* Parameters used to convert the timespec values: */ @@ -44,6 +51,16 @@ static inline struct timespec64 timespec_to_timespec64(const struct timespec ts) return ts; } +static inline struct itimerspec itimerspec64_to_itimerspec(struct itimerspec64 *its64) +{ + return *its64; +} + +static inline struct itimerspec64 itimerspec_to_itimerspec64(struct itimerspec *its) +{ + return *its; +} + # define timespec64_equal timespec_equal # define timespec64_compare timespec_compare # define set_normalized_timespec64 set_normalized_timespec @@ -76,6 +93,24 @@ static inline struct timespec64 timespec_to_timespec64(const struct timespec ts) return ret; } +static inline struct itimerspec itimerspec64_to_itimerspec(struct itimerspec64 *its64) +{ + struct itimerspec ret; + + ret.it_interval = timespec64_to_timespec(its64->it_interval); + ret.it_value = timespec64_to_timespec(its64->it_value); + return ret; +} + +static inline struct itimerspec64 itimerspec_to_itimerspec64(struct itimerspec *its) +{ + struct itimerspec64 ret; + + ret.it_interval = timespec_to_timespec64(its->it_interval); + ret.it_value = timespec_to_timespec64(its->it_value); + return ret; +} + static inline int timespec64_equal(const struct timespec64 *a, const struct timespec64 *b) { -- 1.7.9.5

10 years

[PATCH v4 04/25] security/security: Introduce security_settime64() function with timespec64 type

by Baolin Wang

For introducing the do_sys_settimeofday64() function with timespec64 type to make it ready for 2038 issue, it need to introduce the security_settime64() function with timespec64 type firstly. Also introduce a default security_settime64() function with timespec64 type when it hasn't defined the CONFIG_SECURITY macro. Also this patch changes the "settime" pointer's argument with timespec64 type in security_operations structure for introducing the the security_settime64() function. Meanwhile moves the security_settime() defined in security/security.c file to include/linux/security.h file as a static function, that makes it convenient to delete the security_settime() later. And change the cap_settime() function's argument with timespec64 type to make it ready for 2038 issue, which is only used by security_settime64()/security_settime() function. Signed-off-by: Baolin Wang <baolin.wang(a)linaro.org> --- include/linux/security.h | 25 ++++++++++++++++++++----- security/commoncap.c | 2 +- security/security.c | 2 +- 3 files changed, 22 insertions(+), 7 deletions(-) diff --git a/include/linux/security.h b/include/linux/security.h index a1b7dbd..5288794 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -75,7 +75,7 @@ struct timezone; */ extern int cap_capable(const struct cred *cred, struct user_namespace *ns, int cap, int audit); -extern int cap_settime(const struct timespec *ts, const struct timezone *tz); +extern int cap_settime(const struct timespec64 *ts, const struct timezone *tz); extern int cap_ptrace_access_check(struct task_struct *child, unsigned int mode); extern int cap_ptrace_traceme(struct task_struct *parent); extern int cap_capget(struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted); @@ -1353,7 +1353,8 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * Return 0 if permission is granted. * @settime: * Check permission to change the system time. - * struct timespec and timezone are defined in include/linux/time.h + * struct timespec64 is defined in include/linux/time64.h and timezone is + * defined in include/linux/time.h * @ts contains new time * @tz contains new timezone * Return 0 if permission is granted. @@ -1483,7 +1484,7 @@ struct security_operations { int (*quotactl) (int cmds, int type, int id, struct super_block *sb); int (*quota_on) (struct dentry *dentry); int (*syslog) (int type); - int (*settime) (const struct timespec *ts, const struct timezone *tz); + int (*settime) (const struct timespec64 *ts, const struct timezone *tz); int (*vm_enough_memory) (struct mm_struct *mm, long pages); int (*bprm_set_creds) (struct linux_binprm *bprm); @@ -1790,7 +1791,13 @@ int security_capable_noaudit(const struct cred *cred, struct user_namespace *ns, int security_quotactl(int cmds, int type, int id, struct super_block *sb); int security_quota_on(struct dentry *dentry); int security_syslog(int type); -int security_settime(const struct timespec *ts, const struct timezone *tz); +int security_settime64(const struct timespec64 *ts, const struct timezone *tz); +static int security_settime(const struct timespec *ts, const struct timezone *tz) +{ + struct timespec64 ts64 = timespec_to_timespec64(*ts); + + return security_settime64(&ts64, tz); +} int security_vm_enough_memory_mm(struct mm_struct *mm, long pages); int security_bprm_set_creds(struct linux_binprm *bprm); int security_bprm_check(struct linux_binprm *bprm); @@ -2040,10 +2047,18 @@ static inline int security_syslog(int type) return 0; } +static inline int security_settime64(const struct timespec64 *ts, + const struct timezone *tz) +{ + return cap_settime(ts, tz); +} + static inline int security_settime(const struct timespec *ts, const struct timezone *tz) { - return cap_settime(ts, tz); + struct timsepc64 ts64 = timespec_to_timespec64(*ts); + + return cap_settime(&ts64, tz); } static inline int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) diff --git a/security/commoncap.c b/security/commoncap.c index f66713b..bdb8ec0 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -116,7 +116,7 @@ int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, * Determine whether the current process may set the system clock and timezone * information, returning 0 if permission granted, -ve if denied. */ -int cap_settime(const struct timespec *ts, const struct timezone *tz) +int cap_settime(const struct timespec64 *ts, const struct timezone *tz) { if (!capable(CAP_SYS_TIME)) return -EPERM; diff --git a/security/security.c b/security/security.c index e81d5bb..0be5032 100644 --- a/security/security.c +++ b/security/security.c @@ -224,7 +224,7 @@ int security_syslog(int type) return security_ops->syslog(type); } -int security_settime(const struct timespec *ts, const struct timezone *tz) +int security_settime64(const struct timespec64 *ts, const struct timezone *tz) { return security_ops->settime(ts, tz); } -- 1.7.9.5

10 years

[PATCH] Staging: media: lirc: Replace timeval with ktime_t

by Ksenija Stanojevic

'struct timeval last_tv' is used to get the time of last signal change and 'struct timeval last_intr_tv' is used to get the time of last UART interrupt. 32-bit systems using 'struct timeval' will break in the year 2038, so we have to replace that code with more appropriate types. Here struct timeval is replaced with ktime_t. Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic(a)gmail.com> --- drivers/staging/media/lirc/lirc_sir.c | 75 ++++++++++++++--------------------- 1 file changed, 30 insertions(+), 45 deletions(-) diff --git a/drivers/staging/media/lirc/lirc_sir.c b/drivers/staging/media/lirc/lirc_sir.c index 29087f6..4f326e9 100644 --- a/drivers/staging/media/lirc/lirc_sir.c +++ b/drivers/staging/media/lirc/lirc_sir.c @@ -44,7 +44,7 @@ #include <linux/ioport.h> #include <linux/kernel.h> #include <linux/serial_reg.h> -#include <linux/time.h> +#include <linux/ktime.h> #include <linux/string.h> #include <linux/types.h> #include <linux/wait.h> @@ -127,9 +127,9 @@ static int threshold = 3; static DEFINE_SPINLOCK(timer_lock); static struct timer_list timerlist; /* time of last signal change detected */ -static struct timeval last_tv = {0, 0}; +static ktime_t last; /* time of last UART data ready interrupt */ -static struct timeval last_intr_tv = {0, 0}; +static ktime_t last_intr_time; static int last_value; static DECLARE_WAIT_QUEUE_HEAD(lirc_read_queue); @@ -400,20 +400,6 @@ static void drop_chrdev(void) } /* SECTION: Hardware */ -static long delta(struct timeval *tv1, struct timeval *tv2) -{ - unsigned long deltv; - - deltv = tv2->tv_sec - tv1->tv_sec; - if (deltv > 15) - deltv = 0xFFFFFF; - else - deltv = deltv*1000000 + - tv2->tv_usec - - tv1->tv_usec; - return deltv; -} - static void sir_timeout(unsigned long data) { /* @@ -432,12 +418,14 @@ static void sir_timeout(unsigned long data) /* clear unread bits in UART and restart */ outb(UART_FCR_CLEAR_RCVR, io + UART_FCR); /* determine 'virtual' pulse end: */ - pulse_end = delta(&last_tv, &last_intr_tv); + pulse_end = min_t(unsigned long, + ktime_us_delta(last, last_intr_time), + PULSE_MASK); dev_dbg(driver.dev, "timeout add %d for %lu usec\n", last_value, pulse_end); add_read_queue(last_value, pulse_end); last_value = 0; - last_tv = last_intr_tv; + last = last_intr_time; } spin_unlock_irqrestore(&timer_lock, flags); } @@ -445,9 +433,9 @@ static void sir_timeout(unsigned long data) static irqreturn_t sir_interrupt(int irq, void *dev_id) { unsigned char data; - struct timeval curr_tv; - static unsigned long deltv; - unsigned long deltintrtv; + ktime_t curr_time; + static unsigned long delt; + unsigned long deltintr; unsigned long flags; int iir, lsr; @@ -471,49 +459,46 @@ static irqreturn_t sir_interrupt(int irq, void *dev_id) do { del_timer(&timerlist); data = inb(io + UART_RX); - do_gettimeofday(&curr_tv); - deltv = delta(&last_tv, &curr_tv); - deltintrtv = delta(&last_intr_tv, &curr_tv); + curr_time = ktime_get(); + delt = min_t(unsigned long, + ktime_us_delta(last, curr_time), + PULSE_MASK); + deltintr = min_t(unsigned long, + ktime_us_delta(last_intr_time, + curr_time), + PULSE_MASK); dev_dbg(driver.dev, "t %lu, d %d\n", - deltintrtv, (int)data); + deltintr, (int)data); /* * if nothing came in last X cycles, * it was gap */ - if (deltintrtv > TIME_CONST * threshold) { + if (deltintr > TIME_CONST * threshold) { if (last_value) { dev_dbg(driver.dev, "GAP\n"); /* simulate signal change */ add_read_queue(last_value, - deltv - - deltintrtv); + delt - + deltintr); last_value = 0; - last_tv.tv_sec = - last_intr_tv.tv_sec; - last_tv.tv_usec = - last_intr_tv.tv_usec; - deltv = deltintrtv; + last = last_intr_time; + delt = deltintr; } } data = 1; if (data ^ last_value) { /* - * deltintrtv > 2*TIME_CONST, remember? + * deltintr > 2*TIME_CONST, remember? * the other case is timeout */ add_read_queue(last_value, - deltv-TIME_CONST); + delt-TIME_CONST); last_value = data; - last_tv = curr_tv; - if (last_tv.tv_usec >= TIME_CONST) { - last_tv.tv_usec -= TIME_CONST; - } else { - last_tv.tv_sec--; - last_tv.tv_usec += 1000000 - - TIME_CONST; - } + last = curr_time; + last = ktime_sub_us(last, + TIME_CONST); } - last_intr_tv = curr_tv; + last_intr_time = curr_time; if (data) { /* * start timer for end of -- 1.9.1

10 years

[PATCH v2] xen/pcifront: Remove usage of struct timeval

by Tina Ruchandani

struct timeval uses a 32-bit field for representing seconds, which will overflow in the year 2038 and beyond. This patch replaces struct timeval with 64-bit ktime_t which is 2038 safe. The patch is part of a larger effort to remove instances of 32-bit timekeeping variables (timeval, time_t and timespec) from the kernel. Signed-off-by: Tina Ruchandani <ruchandani.tina(a)gmail.com> Suggested-by: Arnd Bergmann <arnd(a)arndb.de> -- Changes in v2: - Use monotonic time (ktime_get_ns()) instead of real time since we only care about elapsed delta here. - Use macro ktime_get_ns() instead of getting ktime_t and converting it to ns. --- drivers/pci/xen-pcifront.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index 7cfd2db..c4796c8 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -20,6 +20,7 @@ #include <linux/workqueue.h> #include <linux/bitops.h> #include <linux/time.h> +#include <linux/ktime.h> #include <xen/platform_pci.h> #include <asm/xen/swiotlb-xen.h> @@ -115,7 +116,6 @@ static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op) evtchn_port_t port = pdev->evtchn; unsigned irq = pdev->irq; s64 ns, ns_timeout; - struct timeval tv; spin_lock_irqsave(&pdev->sh_info_lock, irq_flags); @@ -132,8 +132,7 @@ static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op) * (in the latter case we end up continually re-executing poll() with a * timeout in the past). 1s difference gives plenty of slack for error. */ - do_gettimeofday(&tv); - ns_timeout = timeval_to_ns(&tv) + 2 * (s64)NSEC_PER_SEC; + ns_timeout = ktime_get_ns() + 2 * (s64)NSEC_PER_SEC; xen_clear_irq_pending(irq); @@ -141,8 +140,7 @@ static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op) (unsigned long *)&pdev->sh_info->flags)) { xen_poll_irq_timeout(irq, jiffies + 3*HZ); xen_clear_irq_pending(irq); - do_gettimeofday(&tv); - ns = timeval_to_ns(&tv); + ns = ktime_get_ns(); if (ns > ns_timeout) { dev_err(&pdev->xdev->dev, "pciback not responding!!!\n"); -- 2.2.0.rc0.207.ga3a616c

10 years

Re: [Y2038] [PATCH] fbdev: radeon: Remove 'struct timeval' usage

by Tina Ruchandani

>>> + hz = 1000000/delta; > > This needs to be on of the do_div family. > > Dave. Hi Dave, I build-tested the patch for both 32-bit and 64-bit x86. If my understanding is correct, since the divisor is 64-bit here, the compiler will do "if (delta > 1000000) hz = 0; else hz = 1000000/(s32)delta" automatically? In general, is this a good thumb-rule to follow - use do_div if the dividend is 64-bit, and normal divide operator if only the divisor is 64-bit? Tina

10 years

[PATCH v4 06/25] time/posix-timers:Introduce {get, put}_timespec and {get, put}_itimerspec

by Baolin Wang

These are new helper functions that convert between a user timespec/ itimerspec and a kernel timespec64/itimerspec64 structure. These macros can change the types underneath from both ends and it will work efficiently on both 32-bit and 64-bit that can avoid the CONFIG_64BIT macro in syscall functions, and also it can make the syscall functions more simple. Signed-off-by: Baolin Wang <baolin.wang(a)linaro.org> --- kernel/time/posix-timers.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index 31ea01f..96efe1d 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -147,6 +147,35 @@ static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags); __timr; \ }) +#define __get_timespec(kts, uts) \ + (__get_user((kts)->tv_sec, &(uts)->tv_sec) || \ + __get_user((kts)->tv_nsec, &(uts)->tv_nsec)) + +#define __put_timespec(kts, uts) \ + (__put_user((kts)->tv_sec, &(uts)->tv_sec) || \ + __put_user((kts)->tv_nsec, &(uts)->tv_nsec)) + +#define get_timespec(kts, uts) \ + ((access_ok(VERIFY_READ, (uts), sizeof(*(uts))) || \ + __get_timespec((kts), (uts))) ? \ + -EFAULT : 0) + +#define put_timespec(kts, uts) \ + ((access_ok(VERIFY_WRITE, (uts), sizeof(*(uts))) || \ + __put_timespec((kts), (uts))) ? \ + -EFAULT : 0) + +#define get_itimerspec(kit, uit) \ + ((access_ok(VERIFY_READ, (uit), sizeof(*(uit))) || \ + __get_timespec(&(kit)->it_interval, &(uit)->it_interval) || \ + __get_timespec(&(kit)->it_value, &(uit)->it_value))) + +#define put_itimerspec(kit, uit) \ + ((access_ok(VERIFY_WRITE, (uit), sizeof(*(uit))) || \ + __put_timespec(&(kit)->it_interval, &(uit)->it_interval) || \ + __put_timespec(&(kit)->it_value, &(uit)->it_value)) ? \ + -EFAULT : 0) + static int hash(struct signal_struct *sig, unsigned int nr) { return hash_32(hash32_ptr(sig) ^ nr, HASH_BITS(posix_timers_hashtable)); -- 1.7.9.5

10 years

Re: [Y2038] [PATCH] fbdev: radeon: Remove 'struct timeval' usage

by Dave Airlie

On 3 June 2015 at 21:59, Tomi Valkeinen <tomi.valkeinen(a)ti.com> wrote: > > > On 25/05/15 07:07, Tina Ruchandani wrote: >> 'struct timeval' uses a 32-bit representation for the >> seconds field which will overflow in the year 2038 and beyond. >> This patch replaces the usage of 'struct timeval' with >> ktime_t which uses a 64-bit time representation and does not >> suffer from the y2038 problem. This patch is part of a larger >> effort to remove all instances of 'struct timeval', 'struct >> timespec', time_t and other 32-bit timekeeping variables >> from the kernel. >> The patch also replaces the use of real time (do_gettimeofday) >> with monotonic time (ktime_get). >> >> Signed-off-by: Tina Ruchandani <ruchandani.tina(a)gmail.com> >> --- >> drivers/video/fbdev/aty/radeon_base.c | 29 ++++++++++++++--------------- >> 1 file changed, 14 insertions(+), 15 deletions(-) >> >> diff --git a/drivers/video/fbdev/aty/radeon_base.c b/drivers/video/fbdev/aty/radeon_base.c >> index 01237c8..9747e9e 100644 >> --- a/drivers/video/fbdev/aty/radeon_base.c >> +++ b/drivers/video/fbdev/aty/radeon_base.c >> @@ -64,6 +64,7 @@ >> #include <linux/slab.h> >> #include <linux/delay.h> >> #include <linux/time.h> >> +#include <linux/ktime.h> >> #include <linux/fb.h> >> #include <linux/ioport.h> >> #include <linux/init.h> >> @@ -461,8 +462,8 @@ static int radeon_probe_pll_params(struct radeonfb_info *rinfo) >> int hTotal, vTotal, num, denom, m, n; >> unsigned long long hz, vclk; >> long xtal; >> - struct timeval start_tv, stop_tv; >> - long total_secs, total_usecs; >> + ktime_t start, stop; >> + s64 delta; >> int i; >> >> /* Ugh, we cut interrupts, bad bad bad, but we want some precision >> @@ -478,7 +479,7 @@ static int radeon_probe_pll_params(struct radeonfb_info *rinfo) >> if (((INREG(CRTC_VLINE_CRNT_VLINE) >> 16) & 0x3ff) == 0) >> break; >> >> - do_gettimeofday(&start_tv); >> + start = ktime_get(); >> >> for(i=0; i<1000000; i++) >> if (((INREG(CRTC_VLINE_CRNT_VLINE) >> 16) & 0x3ff) != 0) >> @@ -487,20 +488,18 @@ static int radeon_probe_pll_params(struct radeonfb_info *rinfo) >> for(i=0; i<1000000; i++) >> if (((INREG(CRTC_VLINE_CRNT_VLINE) >> 16) & 0x3ff) == 0) >> break; >> - >> - do_gettimeofday(&stop_tv); >> - >> + >> + stop = ktime_get(); >> + >> local_irq_enable(); >> >> - total_secs = stop_tv.tv_sec - start_tv.tv_sec; >> - if (total_secs > 10) >> + delta = ktime_us_delta(stop, start); >> + >> + /* Return -1 if more than 10 seconds have elapsed */ >> + if (delta > (10*1000000)) >> return -1; >> - total_usecs = stop_tv.tv_usec - start_tv.tv_usec; >> - total_usecs += total_secs * 1000000; >> - if (total_usecs < 0) >> - total_usecs = -total_usecs; >> - hz = 1000000/total_usecs; >> - >> + hz = 1000000/delta; This needs to be on of the do_div family. Dave.

10 years

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