From: Anthony PERARD <anthony.per...@citrix.com> This function allows to unlock a ram_ptr give by qemu_get_ram_ptr. After a call to qemu_ram_ptr_unlock, the pointer may be unmap from QEMU when used with Xen.
Signed-off-by: Anthony PERARD <anthony.per...@citrix.com> --- cpu-common.h | 1 + exec.c | 10 ++++++++++ xen-mapcache.c | 34 ++++++++++++++++++++++++++++++++++ 3 files changed, 45 insertions(+), 0 deletions(-) diff --git a/cpu-common.h b/cpu-common.h index 0426bc8..378eea8 100644 --- a/cpu-common.h +++ b/cpu-common.h @@ -46,6 +46,7 @@ ram_addr_t qemu_ram_alloc(DeviceState *dev, const char *name, ram_addr_t size); void qemu_ram_free(ram_addr_t addr); /* This should only be used for ram local to a device. */ void *qemu_get_ram_ptr(ram_addr_t addr); +void qemu_ram_ptr_unlock(void *addr); /* This should not be used by devices. */ ram_addr_t qemu_ram_addr_from_host(void *ptr); diff --git a/exec.c b/exec.c index ed42837..6e3276c 100644 --- a/exec.c +++ b/exec.c @@ -2958,6 +2958,13 @@ void *qemu_get_ram_ptr(ram_addr_t addr) return NULL; } +void qemu_ram_ptr_unlock(void *addr) +{ + if (xen_mapcache_enabled()) { + qemu_map_cache_unlock(addr); + } +} + /* Some of the softmmu routines need to translate from a host pointer (typically a TLB entry) back to a ram offset. */ ram_addr_t qemu_ram_addr_from_host(void *ptr) @@ -3537,6 +3544,7 @@ void cpu_physical_memory_rw(target_phys_addr_t addr, uint8_t *buf, cpu_physical_memory_set_dirty_flags( addr1, (0xff & ~CODE_DIRTY_FLAG)); } + qemu_ram_ptr_unlock(ptr); } } else { if ((pd & ~TARGET_PAGE_MASK) > IO_MEM_ROM && @@ -3567,6 +3575,7 @@ void cpu_physical_memory_rw(target_phys_addr_t addr, uint8_t *buf, ptr = qemu_get_ram_ptr(pd & TARGET_PAGE_MASK) + (addr & ~TARGET_PAGE_MASK); memcpy(buf, ptr, l); + qemu_ram_ptr_unlock(ptr); } } len -= l; @@ -3607,6 +3616,7 @@ void cpu_physical_memory_write_rom(target_phys_addr_t addr, /* ROM/RAM case */ ptr = qemu_get_ram_ptr(addr1); memcpy(ptr, buf, l); + qemu_ram_ptr_unlock(ptr); } len -= l; buf += l; diff --git a/xen-mapcache.c b/xen-mapcache.c index c7e69e6..e407949 100644 --- a/xen-mapcache.c +++ b/xen-mapcache.c @@ -187,6 +187,40 @@ uint8_t *qemu_map_cache(target_phys_addr_t phys_addr, target_phys_addr_t size, u return mapcache->last_address_vaddr + address_offset; } +void qemu_map_cache_unlock(void *buffer) +{ + MapCacheEntry *entry = NULL, *pentry = NULL; + MapCacheRev *reventry; + target_phys_addr_t paddr_index; + int found = 0; + + QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) { + if (reventry->vaddr_req == buffer) { + paddr_index = reventry->paddr_index; + found = 1; + break; + } + } + if (!found) { + return; + } + QTAILQ_REMOVE(&mapcache->locked_entries, reventry, next); + qemu_free(reventry); + + entry = &mapcache->entry[paddr_index % mapcache->nr_buckets]; + while (entry && entry->paddr_index != paddr_index) { + pentry = entry; + entry = entry->next; + } + if (!entry) { + return; + } + entry->lock--; + if (entry->lock > 0) { + entry->lock--; + } +} + ram_addr_t qemu_ram_addr_from_mapcache(void *ptr) { MapCacheRev *reventry; -- 1.7.1