diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Kconfig.debug | 9 | ||||
-rw-r--r-- | lib/Makefile | 1 | ||||
-rw-r--r-- | lib/bitmap.c | 50 | ||||
-rw-r--r-- | lib/kstrtox.c | 6 | ||||
-rw-r--r-- | lib/percpu-refcount.c | 169 | ||||
-rw-r--r-- | lib/strncpy_from_user.c | 2 |
6 files changed, 145 insertions, 92 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 39d07e754822..33bc56cf60d7 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1857,15 +1857,6 @@ config PROVIDE_OHCI1394_DMA_INIT See Documentation/debugging-via-ohci1394.txt for more information. -config BUILD_DOCSRC - bool "Build targets in Documentation/ tree" - depends on HEADERS_CHECK - help - This option attempts to build objects from the source files in the - kernel Documentation/ tree. - - Say N if you are unsure. - config DMA_API_DEBUG bool "Enable debugging of DMA-API usage" depends on HAVE_DMA_API_DEBUG diff --git a/lib/Makefile b/lib/Makefile index f3ca8c0ab634..50144a3aeebd 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -180,6 +180,7 @@ obj-$(CONFIG_IRQ_POLL) += irq_poll.o obj-$(CONFIG_STACKDEPOT) += stackdepot.o KASAN_SANITIZE_stackdepot.o := n +KCOV_INSTRUMENT_stackdepot.o := n libfdt_files = fdt.o fdt_ro.o fdt_wip.o fdt_rw.o fdt_sw.o fdt_strerror.o \ fdt_empty_tree.o diff --git a/lib/bitmap.c b/lib/bitmap.c index eca88087fa8a..0b66f0e5eb6b 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -496,6 +496,11 @@ EXPORT_SYMBOL(bitmap_print_to_pagebuf); * ranges. Consecutively set bits are shown as two hyphen-separated * decimal numbers, the smallest and largest bit numbers set in * the range. + * Optionally each range can be postfixed to denote that only parts of it + * should be set. The range will divided to groups of specific size. + * From each group will be used only defined amount of bits. + * Syntax: range:used_size/group_size + * Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769 * * Returns 0 on success, -errno on invalid input strings. * Error values: @@ -507,16 +512,20 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen, int is_user, unsigned long *maskp, int nmaskbits) { - unsigned a, b; + unsigned int a, b, old_a, old_b; + unsigned int group_size, used_size; int c, old_c, totaldigits, ndigits; const char __user __force *ubuf = (const char __user __force *)buf; - int at_start, in_range; + int at_start, in_range, in_partial_range; totaldigits = c = 0; + old_a = old_b = 0; + group_size = used_size = 0; bitmap_zero(maskp, nmaskbits); do { at_start = 1; in_range = 0; + in_partial_range = 0; a = b = 0; ndigits = totaldigits; @@ -547,6 +556,24 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen, if ((totaldigits != ndigits) && isspace(old_c)) return -EINVAL; + if (c == '/') { + used_size = a; + at_start = 1; + in_range = 0; + a = b = 0; + continue; + } + + if (c == ':') { + old_a = a; + old_b = b; + at_start = 1; + in_range = 0; + in_partial_range = 1; + a = b = 0; + continue; + } + if (c == '-') { if (at_start || in_range) return -EINVAL; @@ -567,15 +594,30 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen, } if (ndigits == totaldigits) continue; + if (in_partial_range) { + group_size = a; + a = old_a; + b = old_b; + old_a = old_b = 0; + } /* if no digit is after '-', it's wrong*/ if (at_start && in_range) return -EINVAL; - if (!(a <= b)) + if (!(a <= b) || !(used_size <= group_size)) return -EINVAL; if (b >= nmaskbits) return -ERANGE; while (a <= b) { - set_bit(a, maskp); + if (in_partial_range) { + static int pos_in_group = 1; + + if (pos_in_group <= used_size) + set_bit(a, maskp); + + if (a == b || ++pos_in_group > group_size) + pos_in_group = 1; + } else + set_bit(a, maskp); a++; } } while (buflen && c == ','); diff --git a/lib/kstrtox.c b/lib/kstrtox.c index d8a5cf66c316..b8e2080c1a47 100644 --- a/lib/kstrtox.c +++ b/lib/kstrtox.c @@ -48,11 +48,9 @@ unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long { unsigned long long res; unsigned int rv; - int overflow; res = 0; rv = 0; - overflow = 0; while (*s) { unsigned int val; @@ -71,15 +69,13 @@ unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long */ if (unlikely(res & (~0ull << 60))) { if (res > div_u64(ULLONG_MAX - val, base)) - overflow = 1; + rv |= KSTRTOX_OVERFLOW; } res = res * base + val; rv++; s++; } *p = res; - if (overflow) - rv |= KSTRTOX_OVERFLOW; return rv; } diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c index 27fe74948882..9ac959ef4cae 100644 --- a/lib/percpu-refcount.c +++ b/lib/percpu-refcount.c @@ -33,6 +33,7 @@ #define PERCPU_COUNT_BIAS (1LU << (BITS_PER_LONG - 1)) +static DEFINE_SPINLOCK(percpu_ref_switch_lock); static DECLARE_WAIT_QUEUE_HEAD(percpu_ref_switch_waitq); static unsigned long __percpu *percpu_count_ptr(struct percpu_ref *ref) @@ -82,6 +83,7 @@ int percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release, atomic_long_set(&ref->count, start_count); ref->release = release; + ref->confirm_switch = NULL; return 0; } EXPORT_SYMBOL_GPL(percpu_ref_init); @@ -101,6 +103,8 @@ void percpu_ref_exit(struct percpu_ref *ref) unsigned long __percpu *percpu_count = percpu_count_ptr(ref); if (percpu_count) { + /* non-NULL confirm_switch indicates switching in progress */ + WARN_ON_ONCE(ref->confirm_switch); free_percpu(percpu_count); ref->percpu_count_ptr = __PERCPU_REF_ATOMIC_DEAD; } @@ -161,66 +165,23 @@ static void percpu_ref_noop_confirm_switch(struct percpu_ref *ref) static void __percpu_ref_switch_to_atomic(struct percpu_ref *ref, percpu_ref_func_t *confirm_switch) { - if (!(ref->percpu_count_ptr & __PERCPU_REF_ATOMIC)) { - /* switching from percpu to atomic */ - ref->percpu_count_ptr |= __PERCPU_REF_ATOMIC; - - /* - * Non-NULL ->confirm_switch is used to indicate that - * switching is in progress. Use noop one if unspecified. - */ - WARN_ON_ONCE(ref->confirm_switch); - ref->confirm_switch = - confirm_switch ?: percpu_ref_noop_confirm_switch; - - percpu_ref_get(ref); /* put after confirmation */ - call_rcu_sched(&ref->rcu, percpu_ref_switch_to_atomic_rcu); - } else if (confirm_switch) { - /* - * Somebody already set ATOMIC. Switching may still be in - * progress. @confirm_switch must be invoked after the - * switching is complete and a full sched RCU grace period - * has passed. Wait synchronously for the previous - * switching and schedule @confirm_switch invocation. - */ - wait_event(percpu_ref_switch_waitq, !ref->confirm_switch); - ref->confirm_switch = confirm_switch; - - percpu_ref_get(ref); /* put after confirmation */ - call_rcu_sched(&ref->rcu, percpu_ref_call_confirm_rcu); + if (ref->percpu_count_ptr & __PERCPU_REF_ATOMIC) { + if (confirm_switch) + confirm_switch(ref); + return; } -} -/** - * percpu_ref_switch_to_atomic - switch a percpu_ref to atomic mode - * @ref: percpu_ref to switch to atomic mode - * @confirm_switch: optional confirmation callback - * - * There's no reason to use this function for the usual reference counting. - * Use percpu_ref_kill[_and_confirm](). - * - * Schedule switching of @ref to atomic mode. All its percpu counts will - * be collected to the main atomic counter. On completion, when all CPUs - * are guaraneed to be in atomic mode, @confirm_switch, which may not - * block, is invoked. This function may be invoked concurrently with all - * the get/put operations and can safely be mixed with kill and reinit - * operations. Note that @ref will stay in atomic mode across kill/reinit - * cycles until percpu_ref_switch_to_percpu() is called. - * - * This function normally doesn't block and can be called from any context - * but it may block if @confirm_kill is specified and @ref is already in - * the process of switching to atomic mode. In such cases, @confirm_switch - * will be invoked after the switching is complete. - * - * Due to the way percpu_ref is implemented, @confirm_switch will be called - * after at least one full sched RCU grace period has passed but this is an - * implementation detail and must not be depended upon. - */ -void percpu_ref_switch_to_atomic(struct percpu_ref *ref, - percpu_ref_func_t *confirm_switch) -{ - ref->force_atomic = true; - __percpu_ref_switch_to_atomic(ref, confirm_switch); + /* switching from percpu to atomic */ + ref->percpu_count_ptr |= __PERCPU_REF_ATOMIC; + + /* + * Non-NULL ->confirm_switch is used to indicate that switching is + * in progress. Use noop one if unspecified. + */ + ref->confirm_switch = confirm_switch ?: percpu_ref_noop_confirm_switch; + + percpu_ref_get(ref); /* put after confirmation */ + call_rcu_sched(&ref->rcu, percpu_ref_switch_to_atomic_rcu); } static void __percpu_ref_switch_to_percpu(struct percpu_ref *ref) @@ -233,8 +194,6 @@ static void __percpu_ref_switch_to_percpu(struct percpu_ref *ref) if (!(ref->percpu_count_ptr & __PERCPU_REF_ATOMIC)) return; - wait_event(percpu_ref_switch_waitq, !ref->confirm_switch); - atomic_long_add(PERCPU_COUNT_BIAS, &ref->count); /* @@ -250,6 +209,58 @@ static void __percpu_ref_switch_to_percpu(struct percpu_ref *ref) ref->percpu_count_ptr & ~__PERCPU_REF_ATOMIC); } +static void __percpu_ref_switch_mode(struct percpu_ref *ref, + percpu_ref_func_t *confirm_switch) +{ + lockdep_assert_held(&percpu_ref_switch_lock); + + /* + * If the previous ATOMIC switching hasn't finished yet, wait for + * its completion. If the caller ensures that ATOMIC switching + * isn't in progress, this function can be called from any context. + */ + wait_event_lock_irq(percpu_ref_switch_waitq, !ref->confirm_switch, + percpu_ref_switch_lock); + + if (ref->force_atomic || (ref->percpu_count_ptr & __PERCPU_REF_DEAD)) + __percpu_ref_switch_to_atomic(ref, confirm_switch); + else + __percpu_ref_switch_to_percpu(ref); +} + +/** + * percpu_ref_switch_to_atomic - switch a percpu_ref to atomic mode + * @ref: percpu_ref to switch to atomic mode + * @confirm_switch: optional confirmation callback + * + * There's no reason to use this function for the usual reference counting. + * Use percpu_ref_kill[_and_confirm](). + * + * Schedule switching of @ref to atomic mode. All its percpu counts will + * be collected to the main atomic counter. On completion, when all CPUs + * are guaraneed to be in atomic mode, @confirm_switch, which may not + * block, is invoked. This function may be invoked concurrently with all + * the get/put operations and can safely be mixed with kill and reinit + * operations. Note that @ref will stay in atomic mode across kill/reinit + * cycles until percpu_ref_switch_to_percpu() is called. + * + * This function may block if @ref is in the process of switching to atomic + * mode. If the caller ensures that @ref is not in the process of + * switching to atomic mode, this function can be called from any context. + */ +void percpu_ref_switch_to_atomic(struct percpu_ref *ref, + percpu_ref_func_t *confirm_switch) +{ + unsigned long flags; + + spin_lock_irqsave(&percpu_ref_switch_lock, flags); + + ref->force_atomic = true; + __percpu_ref_switch_mode(ref, confirm_switch); + + spin_unlock_irqrestore(&percpu_ref_switch_lock, flags); +} + /** * percpu_ref_switch_to_percpu - switch a percpu_ref to percpu mode * @ref: percpu_ref to switch to percpu mode @@ -264,17 +275,20 @@ static void __percpu_ref_switch_to_percpu(struct percpu_ref *ref) * dying or dead, the actual switching takes place on the following * percpu_ref_reinit(). * - * This function normally doesn't block and can be called from any context - * but it may block if @ref is in the process of switching to atomic mode - * by percpu_ref_switch_atomic(). + * This function may block if @ref is in the process of switching to atomic + * mode. If the caller ensures that @ref is not in the process of + * switching to atomic mode, this function can be called from any context. */ void percpu_ref_switch_to_percpu(struct percpu_ref *ref) { + unsigned long flags; + + spin_lock_irqsave(&percpu_ref_switch_lock, flags); + ref->force_atomic = false; + __percpu_ref_switch_mode(ref, NULL); - /* a dying or dead ref can't be switched to percpu mode w/o reinit */ - if (!(ref->percpu_count_ptr & __PERCPU_REF_DEAD)) - __percpu_ref_switch_to_percpu(ref); + spin_unlock_irqrestore(&percpu_ref_switch_lock, flags); } /** @@ -290,21 +304,23 @@ void percpu_ref_switch_to_percpu(struct percpu_ref *ref) * * This function normally doesn't block and can be called from any context * but it may block if @confirm_kill is specified and @ref is in the - * process of switching to atomic mode by percpu_ref_switch_atomic(). - * - * Due to the way percpu_ref is implemented, @confirm_switch will be called - * after at least one full sched RCU grace period has passed but this is an - * implementation detail and must not be depended upon. + * process of switching to atomic mode by percpu_ref_switch_to_atomic(). */ void percpu_ref_kill_and_confirm(struct percpu_ref *ref, percpu_ref_func_t *confirm_kill) { + unsigned long flags; + + spin_lock_irqsave(&percpu_ref_switch_lock, flags); + WARN_ONCE(ref->percpu_count_ptr & __PERCPU_REF_DEAD, "%s called more than once on %pf!", __func__, ref->release); ref->percpu_count_ptr |= __PERCPU_REF_DEAD; - __percpu_ref_switch_to_atomic(ref, confirm_kill); + __percpu_ref_switch_mode(ref, confirm_kill); percpu_ref_put(ref); + + spin_unlock_irqrestore(&percpu_ref_switch_lock, flags); } EXPORT_SYMBOL_GPL(percpu_ref_kill_and_confirm); @@ -321,11 +337,16 @@ EXPORT_SYMBOL_GPL(percpu_ref_kill_and_confirm); */ void percpu_ref_reinit(struct percpu_ref *ref) { + unsigned long flags; + + spin_lock_irqsave(&percpu_ref_switch_lock, flags); + WARN_ON_ONCE(!percpu_ref_is_zero(ref)); ref->percpu_count_ptr &= ~__PERCPU_REF_DEAD; percpu_ref_get(ref); - if (!ref->force_atomic) - __percpu_ref_switch_to_percpu(ref); + __percpu_ref_switch_mode(ref, NULL); + + spin_unlock_irqrestore(&percpu_ref_switch_lock, flags); } EXPORT_SYMBOL_GPL(percpu_ref_reinit); diff --git a/lib/strncpy_from_user.c b/lib/strncpy_from_user.c index 9c5fe8110413..7e35fc450c5b 100644 --- a/lib/strncpy_from_user.c +++ b/lib/strncpy_from_user.c @@ -1,6 +1,7 @@ #include <linux/compiler.h> #include <linux/export.h> #include <linux/kasan-checks.h> +#include <linux/thread_info.h> #include <linux/uaccess.h> #include <linux/kernel.h> #include <linux/errno.h> @@ -111,6 +112,7 @@ long strncpy_from_user(char *dst, const char __user *src, long count) long retval; kasan_check_write(dst, count); + check_object_size(dst, count, false); user_access_begin(); retval = do_strncpy_from_user(dst, src, count, max); user_access_end(); |