From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=58797 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PiEXe-0004bV-CY for qemu-devel@nongnu.org; Wed, 26 Jan 2011 18:12:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PiEVH-0002nV-VK for qemu-devel@nongnu.org; Wed, 26 Jan 2011 18:10:21 -0500 Received: from mail-qy0-f173.google.com ([209.85.216.173]:54562) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PiEVH-0002nP-QI for qemu-devel@nongnu.org; Wed, 26 Jan 2011 18:10:19 -0500 Received: by qyl38 with SMTP id 38so6600133qyl.4 for ; Wed, 26 Jan 2011 15:10:19 -0800 (PST) Message-ID: <4D40A9D4.8020707@codemonkey.ws> Date: Wed, 26 Jan 2011 17:10:12 -0600 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH V9 12/16] Introduce qemu_ram_ptr_unlock. References: <1295965760-31508-1-git-send-email-anthony.perard@citrix.com> <1295965760-31508-13-git-send-email-anthony.perard@citrix.com> In-Reply-To: <1295965760-31508-13-git-send-email-anthony.perard@citrix.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: anthony.perard@citrix.com Cc: Xen Devel , QEMU-devel , Stefano Stabellini On 01/25/2011 08:29 AM, anthony.perard@citrix.com wrote: > From: Anthony PERARD > > 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 > --- > 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 6d4a898..8fa6d80 100644 > --- a/cpu-common.h > +++ b/cpu-common.h > @@ -55,6 +55,7 @@ void *qemu_get_ram_ptr(ram_addr_t addr); > /* Same but slower, to use for migration, where the order of > * RAMBlocks must not change. */ > void *qemu_safe_ram_ptr(ram_addr_t addr); > +void qemu_ram_ptr_unlock(void *addr); > /* This should not be used by devices. */ > int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr); > ram_addr_t qemu_ram_addr_from_host_nofail(void *ptr); > diff --git a/exec.c b/exec.c > index 3b137dc..8acf2a9 100644 > --- a/exec.c > +++ b/exec.c > @@ -2977,6 +2977,13 @@ void *qemu_safe_ram_ptr(ram_addr_t addr) > return NULL; > } > > +void qemu_ram_ptr_unlock(void *addr) > +{ > + if (xen_mapcache_enabled()) { > + qemu_map_cache_unlock(addr); > + } > +} > + > qemu_put_ram_ptr() would be a better name. Regards, Anthony Liguori > int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr) > { > RAMBlock *block; > @@ -3692,6 +3699,7 @@ 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&& > @@ -3722,6 +3730,7 @@ 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; > @@ -3762,6 +3771,7 @@ 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 3e1cca9..23a23f9 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; >