From 76b7742c135ad6dac789ee7d27ebf90d188f578b Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Wed, 29 May 2013 16:58:31 +0900 Subject: [PATCH] bus: when adding memfds to cache and we shorten them, make sure to unmap the remainder --- src/libsystemd-bus/bus-kernel.c | 33 ++++++++++++++------------------- 1 file changed, 14 insertions(+), 19 deletions(-) diff --git a/src/libsystemd-bus/bus-kernel.c b/src/libsystemd-bus/bus-kernel.c index 10b7a8aba..0ece1f014 100644 --- a/src/libsystemd-bus/bus-kernel.c +++ b/src/libsystemd-bus/bus-kernel.c @@ -715,12 +715,12 @@ int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *size) { if (!bus || !bus->is_kernel) return -ENOTSUP; - assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) == 0); + assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) >= 0); if (bus->n_memfd_cache <= 0) { int r; - assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) == 0); + assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0); r = ioctl(bus->input_fd, KDBUS_CMD_MEMFD_NEW, &fd); if (r < 0) @@ -740,20 +740,21 @@ int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *size) { *size = c->size; fd = c->fd; - assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) == 0); + assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0); return fd; } static void close_and_munmap(int fd, void *address, size_t size) { if (size > 0) - assert_se(munmap(address, PAGE_ALIGN(size)) == 0); + assert_se(munmap(address, PAGE_ALIGN(size)) >= 0); close_nointr_nofail(fd); } void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t size) { struct memfd_cache *c; + uint64_t max_sz = PAGE_ALIGN(MEMFD_CACHE_ITEM_SIZE_MAX); assert(fd >= 0); assert(size == 0 || address); @@ -763,10 +764,10 @@ void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t size) { return; } - assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) == 0); + assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) >= 0); if (bus->n_memfd_cache >= ELEMENTSOF(bus->memfd_cache)) { - assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) == 0); + assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0); close_and_munmap(fd, address, size); return; @@ -777,16 +778,14 @@ void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t size) { c->address = address; /* If overly long, let's return a bit to the OS */ - if (size > MEMFD_CACHE_ITEM_SIZE_MAX) { - uint64_t sz = MEMFD_CACHE_ITEM_SIZE_MAX; - - ioctl(bus->input_fd, KDBUS_CMD_MEMFD_SIZE_SET, &sz); - - c->size = MEMFD_CACHE_ITEM_SIZE_MAX; + if (size > max_sz) { + assert_se(ioctl(fd, KDBUS_CMD_MEMFD_SIZE_SET, &max_sz) >= 0); + assert_se(munmap((uint8_t*) address + max_sz, PAGE_ALIGN(size - max_sz)) >= 0); + c->size = max_sz; } else c->size = size; - assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) == 0); + assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0); } void bus_kernel_flush_memfd(sd_bus *b) { @@ -794,10 +793,6 @@ void bus_kernel_flush_memfd(sd_bus *b) { assert(b); - for (i = 0; i < b->n_memfd_cache; i++) { - if (b->memfd_cache[i].size > 0) - assert_se(munmap(b->memfd_cache[i].address, PAGE_ALIGN(b->memfd_cache[i].size)) == 0); - - close_nointr_nofail(b->memfd_cache[i].fd); - } + for (i = 0; i < b->n_memfd_cache; i++) + close_and_munmap(b->memfd_cache[i].fd, b->memfd_cache[i].address, b->memfd_cache[i].size); } -- 2.30.2