From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45460) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtPZn-0002LZ-JZ for qemu-devel@nongnu.org; Mon, 02 Nov 2015 19:35:52 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZtPZk-0003EU-Ay for qemu-devel@nongnu.org; Mon, 02 Nov 2015 19:35:51 -0500 Received: from relay-04.andrew.cmu.edu ([128.2.105.169]:45586 helo=relay.andrew.cmu.edu) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtPZk-0003E1-67 for qemu-devel@nongnu.org; Mon, 02 Nov 2015 19:35:48 -0500 From: "Gabriel L. Somlo" Date: Mon, 2 Nov 2015 19:35:45 -0500 Message-Id: <1446510945-18477-6-git-send-email-somlo@cmu.edu> In-Reply-To: <1446510945-18477-1-git-send-email-somlo@cmu.edu> References: <1446510945-18477-1-git-send-email-somlo@cmu.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v3 5/5] fw_cfg: replace ioport data read with generic method List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, jordan.l.justen@intel.com, kraxel@redhat.com, pbonzini@redhat.com, markmb@redhat.com, lersek@redhat.com IOPort read access is limited to one byte at a time by fw_cfg_comb_valid(). As such, fw_cfg_comb_read() may safely ignore its size argument (which will always be 1), and simply call its fw_cfg_read() helper function once, returning 8 bits via the least significant byte of a 64-bit return value. This patch replaces fw_cfg_comb_read() with the generic method fw_cfg_data_read(), and removes the unused fw_cfg_read() helper. When called with size =3D 1, fw_cfg_data_read() acts exactly like fw_cfg_read(), performing the same set of sanity checks, and executing the while loop at most once (subject to the current read offset being within range). Cc: Laszlo Ersek Cc: Gerd Hoffmann Cc: Marc Mar=C3=AD Signed-off-by: Gabriel Somlo --- hw/nvram/fw_cfg.c | 24 +----------------------- 1 file changed, 1 insertion(+), 23 deletions(-) diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c index 8aa980c..7d216f0 100644 --- a/hw/nvram/fw_cfg.c +++ b/hw/nvram/fw_cfg.c @@ -292,22 +292,6 @@ static uint64_t fw_cfg_data_read(void *opaque, hwadd= r addr, unsigned size) return value; } =20 -static uint8_t fw_cfg_read(FWCfgState *s) -{ - int arch =3D !!(s->cur_entry & FW_CFG_ARCH_LOCAL); - FWCfgEntry *e =3D &s->entries[arch][s->cur_entry & FW_CFG_ENTRY_MASK= ]; - uint8_t ret; - - if (s->cur_entry =3D=3D FW_CFG_INVALID || !e->data || s->cur_offset = >=3D e->len) - ret =3D 0; - else { - ret =3D e->data[s->cur_offset++]; - } - - trace_fw_cfg_read(s, ret); - return ret; -} - static void fw_cfg_data_mem_write(void *opaque, hwaddr addr, uint64_t value, unsigned size) { @@ -456,12 +440,6 @@ static bool fw_cfg_ctl_mem_valid(void *opaque, hwadd= r addr, return is_write && size =3D=3D 2; } =20 -static uint64_t fw_cfg_comb_read(void *opaque, hwaddr addr, - unsigned size) -{ - return fw_cfg_read(opaque); -} - static void fw_cfg_comb_write(void *opaque, hwaddr addr, uint64_t value, unsigned size) { @@ -499,7 +477,7 @@ static const MemoryRegionOps fw_cfg_data_mem_ops =3D = { }; =20 static const MemoryRegionOps fw_cfg_comb_mem_ops =3D { - .read =3D fw_cfg_comb_read, + .read =3D fw_cfg_data_read, .write =3D fw_cfg_comb_write, .endianness =3D DEVICE_LITTLE_ENDIAN, .valid.accepts =3D fw_cfg_comb_valid, --=20 2.4.3