From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:48302) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RVm41-0003U5-OZ for qemu-devel@nongnu.org; Wed, 30 Nov 2011 10:27:14 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RVm40-0004Z6-GJ for qemu-devel@nongnu.org; Wed, 30 Nov 2011 10:27:13 -0500 Received: from cantor2.suse.de ([195.135.220.15]:58000 helo=mx2.suse.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RVm40-0004Yl-29 for qemu-devel@nongnu.org; Wed, 30 Nov 2011 10:27:12 -0500 From: =?UTF-8?q?Andreas=20F=C3=A4rber?= Date: Wed, 30 Nov 2011 16:26:21 +0100 Message-Id: <1322666781-6108-1-git-send-email-afaerber@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v2] exec.c: Fix subpage memory access to RAM MemoryRegion List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: =?UTF-8?q?Andreas=20F=C3=A4rber?= , Gleb Natapov , Avi Kivity Commit 95c318f5e1f88d7e5bcc6deac17330fd4806a2d3 (Fix segfault in mmio subpage handling code.) prevented a segfault by making all subpage registrations over an existing memory page perform an unassigned access. Symptoms were writes not taking effect and reads returning zero. Very small page sizes are not currently supported either, so subpage memory areas cannot fully be avoided. Therefore change the previous fix to use a new IO_MEM_SUBPAGE_RAM instead of IO_MEM_UNASSIGNED. Suggested by Avi. Signed-off-by: Andreas F=C3=A4rber Cc: Avi Kivity Cc: Gleb Natapov --- cpu-common.h | 1 + exec.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++++= ++++- 2 files changed, 64 insertions(+), 2 deletions(-) diff --git a/cpu-common.h b/cpu-common.h index c9878ba..3f45428 100644 --- a/cpu-common.h +++ b/cpu-common.h @@ -172,6 +172,7 @@ void cpu_physical_memory_write_rom(target_phys_addr_t= addr, #define IO_MEM_ROM (1 << IO_MEM_SHIFT) /* hardcoded offset */ #define IO_MEM_UNASSIGNED (2 << IO_MEM_SHIFT) #define IO_MEM_NOTDIRTY (3 << IO_MEM_SHIFT) +#define IO_MEM_SUBPAGE_RAM (4 << IO_MEM_SHIFT) =20 /* Acts like a ROM when read and like a device when written. */ #define IO_MEM_ROMD (1) diff --git a/exec.c b/exec.c index 6b92198..6c206ff 100644 --- a/exec.c +++ b/exec.c @@ -3570,6 +3570,63 @@ static CPUWriteMemoryFunc * const subpage_write[] = =3D { &subpage_writel, }; =20 +static uint32_t subpage_ram_readb(void *opaque, target_phys_addr_t addr) +{ + ram_addr_t raddr =3D addr; + void *ptr =3D qemu_get_ram_ptr(raddr); + return ldub_p(ptr); +} + +static void subpage_ram_writeb(void *opaque, target_phys_addr_t addr, + uint32_t value) +{ + ram_addr_t raddr =3D addr; + void *ptr =3D qemu_get_ram_ptr(raddr); + stb_p(ptr, value); +} + +static uint32_t subpage_ram_readw(void *opaque, target_phys_addr_t addr) +{ + ram_addr_t raddr =3D addr; + void *ptr =3D qemu_get_ram_ptr(raddr); + return lduw_p(ptr); +} + +static void subpage_ram_writew(void *opaque, target_phys_addr_t addr, + uint32_t value) +{ + ram_addr_t raddr =3D addr; + void *ptr =3D qemu_get_ram_ptr(raddr); + stw_p(ptr, value); +} + +static uint32_t subpage_ram_readl(void *opaque, target_phys_addr_t addr) +{ + ram_addr_t raddr =3D addr; + void *ptr =3D qemu_get_ram_ptr(raddr); + return ldl_p(ptr); +} + +static void subpage_ram_writel(void *opaque, target_phys_addr_t addr, + uint32_t value) +{ + ram_addr_t raddr =3D addr; + void *ptr =3D qemu_get_ram_ptr(raddr); + stl_p(ptr, value); +} + +static CPUReadMemoryFunc * const subpage_ram_read[] =3D { + &subpage_ram_readb, + &subpage_ram_readw, + &subpage_ram_readl, +}; + +static CPUWriteMemoryFunc * const subpage_ram_write[] =3D { + &subpage_ram_writeb, + &subpage_ram_writew, + &subpage_ram_writel, +}; + static int subpage_register (subpage_t *mmio, uint32_t start, uint32_t e= nd, ram_addr_t memory, ram_addr_t region_offset= ) { @@ -3583,8 +3640,9 @@ static int subpage_register (subpage_t *mmio, uint3= 2_t start, uint32_t end, printf("%s: %p start %08x end %08x idx %08x eidx %08x mem %ld\n", __= func__, mmio, start, end, idx, eidx, memory); #endif - if ((memory & ~TARGET_PAGE_MASK) =3D=3D IO_MEM_RAM) - memory =3D IO_MEM_UNASSIGNED; + if ((memory & ~TARGET_PAGE_MASK) =3D=3D IO_MEM_RAM) { + memory =3D IO_MEM_SUBPAGE_RAM; + } memory =3D (memory >> IO_MEM_SHIFT) & (IO_MEM_NB_ENTRIES - 1); for (; idx <=3D eidx; idx++) { mmio->sub_io_index[idx] =3D memory; @@ -3817,6 +3875,9 @@ static void io_mem_init(void) cpu_register_io_memory_fixed(IO_MEM_NOTDIRTY, error_mem_read, notdirty_mem_write, NULL, DEVICE_NATIVE_ENDIAN); + cpu_register_io_memory_fixed(IO_MEM_SUBPAGE_RAM, subpage_ram_read, + subpage_ram_write, NULL, + DEVICE_NATIVE_ENDIAN); for (i=3D0; i<5; i++) io_mem_used[i] =3D 1; =20 --=20 1.7.7