* [PATCH v2 1/4] fw_cfg: add DMA register
2017-09-19 11:58 [PATCH v2 0/4] fw_cfg: add DMA operations & etc/vmcoreinfo support marcandre.lureau
@ 2017-09-19 11:58 ` marcandre.lureau
2017-09-22 11:05 ` kbuild test robot
2017-09-22 11:45 ` kbuild test robot
2017-09-19 11:58 ` [PATCH v2 2/4] fw_cfg: do DMA read operation marcandre.lureau
` (2 subsequent siblings)
3 siblings, 2 replies; 10+ messages in thread
From: marcandre.lureau @ 2017-09-19 11:58 UTC (permalink / raw)
To: linux-kernel; +Cc: somlo, qemu-devel, mst, Marc-André Lureau
From: Marc-André Lureau <marcandre.lureau@redhat.com>
Add an optional <dma_off> kernel module (or command line) parameter
using the following syntax:
[fw_cfg.]ioport=<size>@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]
or
[fw_cfg.]mmio=<size>@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]
and initializes the register address using given or default offset.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
drivers/firmware/qemu_fw_cfg.c | 53 ++++++++++++++++++++++++++++++++----------
1 file changed, 41 insertions(+), 12 deletions(-)
diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c
index 0e2011636fbb..614037703530 100644
--- a/drivers/firmware/qemu_fw_cfg.c
+++ b/drivers/firmware/qemu_fw_cfg.c
@@ -10,20 +10,21 @@
* and select subsets of aarch64), a Device Tree node (on arm), or using
* a kernel module (or command line) parameter with the following syntax:
*
- * [fw_cfg.]ioport=<size>@<base>[:<ctrl_off>:<data_off>]
+ * [fw_cfg.]ioport=<size>@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]
* or
- * [fw_cfg.]mmio=<size>@<base>[:<ctrl_off>:<data_off>]
+ * [fw_cfg.]mmio=<size>@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]
*
* where:
* <size> := size of ioport or mmio range
* <base> := physical base address of ioport or mmio range
* <ctrl_off> := (optional) offset of control register
* <data_off> := (optional) offset of data register
+ * <dma_off> := (optional) offset of dma register
*
* e.g.:
- * fw_cfg.ioport=2@0x510:0:1 (the default on x86)
+ * fw_cfg.ioport=2@0x510:0:1:4 (the default on x86)
* or
- * fw_cfg.mmio=0xA@0x9020000:8:0 (the default on arm)
+ * fw_cfg.mmio=0xA@0x9020000:8:0:16 (the default on arm)
*/
#include <linux/module.h>
@@ -63,6 +64,7 @@ static resource_size_t fw_cfg_p_size;
static void __iomem *fw_cfg_dev_base;
static void __iomem *fw_cfg_reg_ctrl;
static void __iomem *fw_cfg_reg_data;
+static void __iomem *fw_cfg_reg_dma;
/* atomic access to fw_cfg device (potentially slow i/o, so using mutex) */
static DEFINE_MUTEX(fw_cfg_dev_lock);
@@ -118,12 +120,14 @@ static void fw_cfg_io_cleanup(void)
# if (defined(CONFIG_ARM) || defined(CONFIG_ARM64))
# define FW_CFG_CTRL_OFF 0x08
# define FW_CFG_DATA_OFF 0x00
+# define FW_CFG_DMA_OFF 0x10
# elif (defined(CONFIG_PPC_PMAC) || defined(CONFIG_SPARC32)) /* ppc/mac,sun4m */
# define FW_CFG_CTRL_OFF 0x00
# define FW_CFG_DATA_OFF 0x02
# elif (defined(CONFIG_X86) || defined(CONFIG_SPARC64)) /* x86, sun4u */
# define FW_CFG_CTRL_OFF 0x00
# define FW_CFG_DATA_OFF 0x01
+# define FW_CFG_DMA_OFF 0x04
# else
# error "QEMU FW_CFG not available on this architecture!"
# endif
@@ -133,7 +137,7 @@ static void fw_cfg_io_cleanup(void)
static int fw_cfg_do_platform_probe(struct platform_device *pdev)
{
char sig[FW_CFG_SIG_SIZE];
- struct resource *range, *ctrl, *data;
+ struct resource *range, *ctrl, *data, *dma;
/* acquire i/o range details */
fw_cfg_is_mmio = false;
@@ -170,6 +174,7 @@ static int fw_cfg_do_platform_probe(struct platform_device *pdev)
/* were custom register offsets provided (e.g. on the command line)? */
ctrl = platform_get_resource_byname(pdev, IORESOURCE_REG, "ctrl");
data = platform_get_resource_byname(pdev, IORESOURCE_REG, "data");
+ dma = platform_get_resource_byname(pdev, IORESOURCE_REG, "dma");
if (ctrl && data) {
fw_cfg_reg_ctrl = fw_cfg_dev_base + ctrl->start;
fw_cfg_reg_data = fw_cfg_dev_base + data->start;
@@ -179,6 +184,13 @@ static int fw_cfg_do_platform_probe(struct platform_device *pdev)
fw_cfg_reg_data = fw_cfg_dev_base + FW_CFG_DATA_OFF;
}
+ if (dma)
+ fw_cfg_reg_dma = fw_cfg_dev_base + dma->start;
+#ifdef FW_CFG_DMA_OFF
+ else
+ fw_cfg_reg_dma = fw_cfg_dev_base + FW_CFG_DMA_OFF;
+#endif
+
/* verify fw_cfg device signature */
fw_cfg_read_blob(FW_CFG_SIGNATURE, sig, 0, FW_CFG_SIG_SIZE);
if (memcmp(sig, "QEMU", FW_CFG_SIG_SIZE) != 0) {
@@ -628,6 +640,7 @@ static struct platform_device *fw_cfg_cmdline_dev;
/* use special scanf/printf modifier for phys_addr_t, resource_size_t */
#define PH_ADDR_SCAN_FMT "@%" __PHYS_ADDR_PREFIX "i%n" \
":%" __PHYS_ADDR_PREFIX "i" \
+ ":%" __PHYS_ADDR_PREFIX "i%n" \
":%" __PHYS_ADDR_PREFIX "i%n"
#define PH_ADDR_PR_1_FMT "0x%" __PHYS_ADDR_PREFIX "x@" \
@@ -637,12 +650,15 @@ static struct platform_device *fw_cfg_cmdline_dev;
":%" __PHYS_ADDR_PREFIX "u" \
":%" __PHYS_ADDR_PREFIX "u"
+#define PH_ADDR_PR_4_FMT PH_ADDR_PR_3_FMT \
+ ":%" __PHYS_ADDR_PREFIX "u"
+
static int fw_cfg_cmdline_set(const char *arg, const struct kernel_param *kp)
{
- struct resource res[3] = {};
+ struct resource res[4] = {};
char *str;
phys_addr_t base;
- resource_size_t size, ctrl_off, data_off;
+ resource_size_t size, ctrl_off, data_off, dma_off;
int processed, consumed = 0;
/* only one fw_cfg device can exist system-wide, so if one
@@ -658,19 +674,20 @@ static int fw_cfg_cmdline_set(const char *arg, const struct kernel_param *kp)
/* consume "<size>" portion of command line argument */
size = memparse(arg, &str);
- /* get "@<base>[:<ctrl_off>:<data_off>]" chunks */
+ /* get "@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]" chunks */
processed = sscanf(str, PH_ADDR_SCAN_FMT,
&base, &consumed,
- &ctrl_off, &data_off, &consumed);
+ &ctrl_off, &data_off, &consumed,
+ &dma_off, &consumed);
- /* sscanf() must process precisely 1 or 3 chunks:
+ /* sscanf() must process precisely 1, 3 or 4 chunks:
* <base> is mandatory, optionally followed by <ctrl_off>
- * and <data_off>;
+ * and <data_off>, and <dma_off>;
* there must be no extra characters after the last chunk,
* so str[consumed] must be '\0'.
*/
if (str[consumed] ||
- (processed != 1 && processed != 3))
+ (processed != 1 && processed != 3 && process != 4))
return -EINVAL;
res[0].start = base;
@@ -687,6 +704,11 @@ static int fw_cfg_cmdline_set(const char *arg, const struct kernel_param *kp)
res[2].start = data_off;
res[2].flags = IORESOURCE_REG;
}
+ if (processed > 3) {
+ res[3].name = "dma";
+ res[3].start = dma_off;
+ res[3].flags = IORESOURCE_REG;
+ }
/* "processed" happens to nicely match the number of resources
* we need to pass in to this platform device.
@@ -721,6 +743,13 @@ static int fw_cfg_cmdline_get(char *buf, const struct kernel_param *kp)
fw_cfg_cmdline_dev->resource[0].start,
fw_cfg_cmdline_dev->resource[1].start,
fw_cfg_cmdline_dev->resource[2].start);
+ case 4:
+ return snprintf(buf, PAGE_SIZE, PH_ADDR_PR_4_FMT,
+ resource_size(&fw_cfg_cmdline_dev->resource[0]),
+ fw_cfg_cmdline_dev->resource[0].start,
+ fw_cfg_cmdline_dev->resource[1].start,
+ fw_cfg_cmdline_dev->resource[2].start,
+ fw_cfg_cmdline_dev->resource[3].start);
}
/* Should never get here */
--
2.14.1.146.gd35faa819
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH v2 1/4] fw_cfg: add DMA register
2017-09-19 11:58 ` [PATCH v2 1/4] fw_cfg: add DMA register marcandre.lureau
@ 2017-09-22 11:05 ` kbuild test robot
2017-09-22 11:45 ` kbuild test robot
1 sibling, 0 replies; 10+ messages in thread
From: kbuild test robot @ 2017-09-22 11:05 UTC (permalink / raw)
To: marcandre.lureau
Cc: kbuild-all, linux-kernel, somlo, qemu-devel, mst, Marc-André Lureau
[-- Attachment #1: Type: text/plain, Size: 4265 bytes --]
Hi Marc-André,
[auto build test ERROR on linus/master]
[also build test ERROR on v4.14-rc1 next-20170922]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/marcandre-lureau-redhat-com/fw_cfg-add-DMA-operations-etc-vmcoreinfo-support/20170922-182716
config: i386-randconfig-x009-201738 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All errors (new ones prefixed by >>):
drivers/firmware/qemu_fw_cfg.c: In function 'fw_cfg_cmdline_set':
>> drivers/firmware/qemu_fw_cfg.c:690:43: error: 'process' undeclared (first use in this function)
(processed != 1 && processed != 3 && process != 4))
^~~~~~~
drivers/firmware/qemu_fw_cfg.c:690:43: note: each undeclared identifier is reported only once for each function it appears in
vim +/process +690 drivers/firmware/qemu_fw_cfg.c
639
640 /* use special scanf/printf modifier for phys_addr_t, resource_size_t */
641 #define PH_ADDR_SCAN_FMT "@%" __PHYS_ADDR_PREFIX "i%n" \
642 ":%" __PHYS_ADDR_PREFIX "i" \
643 ":%" __PHYS_ADDR_PREFIX "i%n" \
644 ":%" __PHYS_ADDR_PREFIX "i%n"
645
646 #define PH_ADDR_PR_1_FMT "0x%" __PHYS_ADDR_PREFIX "x@" \
647 "0x%" __PHYS_ADDR_PREFIX "x"
648
649 #define PH_ADDR_PR_3_FMT PH_ADDR_PR_1_FMT \
650 ":%" __PHYS_ADDR_PREFIX "u" \
651 ":%" __PHYS_ADDR_PREFIX "u"
652
653 #define PH_ADDR_PR_4_FMT PH_ADDR_PR_3_FMT \
654 ":%" __PHYS_ADDR_PREFIX "u"
655
656 static int fw_cfg_cmdline_set(const char *arg, const struct kernel_param *kp)
657 {
658 struct resource res[4] = {};
659 char *str;
660 phys_addr_t base;
661 resource_size_t size, ctrl_off, data_off, dma_off;
662 int processed, consumed = 0;
663
664 /* only one fw_cfg device can exist system-wide, so if one
665 * was processed on the command line already, we might as
666 * well stop here.
667 */
668 if (fw_cfg_cmdline_dev) {
669 /* avoid leaking previously registered device */
670 platform_device_unregister(fw_cfg_cmdline_dev);
671 return -EINVAL;
672 }
673
674 /* consume "<size>" portion of command line argument */
675 size = memparse(arg, &str);
676
677 /* get "@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]" chunks */
678 processed = sscanf(str, PH_ADDR_SCAN_FMT,
679 &base, &consumed,
680 &ctrl_off, &data_off, &consumed,
681 &dma_off, &consumed);
682
683 /* sscanf() must process precisely 1, 3 or 4 chunks:
684 * <base> is mandatory, optionally followed by <ctrl_off>
685 * and <data_off>, and <dma_off>;
686 * there must be no extra characters after the last chunk,
687 * so str[consumed] must be '\0'.
688 */
689 if (str[consumed] ||
> 690 (processed != 1 && processed != 3 && process != 4))
691 return -EINVAL;
692
693 res[0].start = base;
694 res[0].end = base + size - 1;
695 res[0].flags = !strcmp(kp->name, "mmio") ? IORESOURCE_MEM :
696 IORESOURCE_IO;
697
698 /* insert register offsets, if provided */
699 if (processed > 1) {
700 res[1].name = "ctrl";
701 res[1].start = ctrl_off;
702 res[1].flags = IORESOURCE_REG;
703 res[2].name = "data";
704 res[2].start = data_off;
705 res[2].flags = IORESOURCE_REG;
706 }
707 if (processed > 3) {
708 res[3].name = "dma";
709 res[3].start = dma_off;
710 res[3].flags = IORESOURCE_REG;
711 }
712
713 /* "processed" happens to nicely match the number of resources
714 * we need to pass in to this platform device.
715 */
716 fw_cfg_cmdline_dev = platform_device_register_simple("fw_cfg",
717 PLATFORM_DEVID_NONE, res, processed);
718 if (IS_ERR(fw_cfg_cmdline_dev))
719 return PTR_ERR(fw_cfg_cmdline_dev);
720
721 return 0;
722 }
723
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 25956 bytes --]
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH v2 1/4] fw_cfg: add DMA register
2017-09-19 11:58 ` [PATCH v2 1/4] fw_cfg: add DMA register marcandre.lureau
2017-09-22 11:05 ` kbuild test robot
@ 2017-09-22 11:45 ` kbuild test robot
1 sibling, 0 replies; 10+ messages in thread
From: kbuild test robot @ 2017-09-22 11:45 UTC (permalink / raw)
To: marcandre.lureau
Cc: kbuild-all, linux-kernel, somlo, qemu-devel, mst, Marc-André Lureau
[-- Attachment #1: Type: text/plain, Size: 8786 bytes --]
Hi Marc-André,
[auto build test WARNING on linus/master]
[also build test WARNING on v4.14-rc1 next-20170922]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/marcandre-lureau-redhat-com/fw_cfg-add-DMA-operations-etc-vmcoreinfo-support/20170922-182716
config: i386-randconfig-x075-201738 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All warnings (new ones prefixed by >>):
In file included from include/uapi/linux/stddef.h:1:0,
from include/linux/stddef.h:4,
from include/uapi/linux/posix_types.h:4,
from include/uapi/linux/types.h:13,
from include/linux/types.h:5,
from include/linux/list.h:4,
from include/linux/module.h:9,
from drivers//firmware/qemu_fw_cfg.c:30:
drivers//firmware/qemu_fw_cfg.c: In function 'fw_cfg_cmdline_set':
drivers//firmware/qemu_fw_cfg.c:690:43: error: 'process' undeclared (first use in this function)
(processed != 1 && processed != 3 && process != 4))
^
include/linux/compiler.h:156:30: note: in definition of macro '__trace_if'
if (__builtin_constant_p(!!(cond)) ? !!(cond) : \
^~~~
>> drivers//firmware/qemu_fw_cfg.c:689:2: note: in expansion of macro 'if'
if (str[consumed] ||
^~
drivers//firmware/qemu_fw_cfg.c:690:43: note: each undeclared identifier is reported only once for each function it appears in
(processed != 1 && processed != 3 && process != 4))
^
include/linux/compiler.h:156:30: note: in definition of macro '__trace_if'
if (__builtin_constant_p(!!(cond)) ? !!(cond) : \
^~~~
>> drivers//firmware/qemu_fw_cfg.c:689:2: note: in expansion of macro 'if'
if (str[consumed] ||
^~
vim +/if +689 drivers//firmware/qemu_fw_cfg.c
75f3e8e4 Gabriel Somlo 2016-01-28 639
75f3e8e4 Gabriel Somlo 2016-01-28 640 /* use special scanf/printf modifier for phys_addr_t, resource_size_t */
75f3e8e4 Gabriel Somlo 2016-01-28 641 #define PH_ADDR_SCAN_FMT "@%" __PHYS_ADDR_PREFIX "i%n" \
75f3e8e4 Gabriel Somlo 2016-01-28 642 ":%" __PHYS_ADDR_PREFIX "i" \
46ebd6f8 Marc-André Lureau 2017-09-19 643 ":%" __PHYS_ADDR_PREFIX "i%n" \
75f3e8e4 Gabriel Somlo 2016-01-28 644 ":%" __PHYS_ADDR_PREFIX "i%n"
75f3e8e4 Gabriel Somlo 2016-01-28 645
75f3e8e4 Gabriel Somlo 2016-01-28 646 #define PH_ADDR_PR_1_FMT "0x%" __PHYS_ADDR_PREFIX "x@" \
75f3e8e4 Gabriel Somlo 2016-01-28 647 "0x%" __PHYS_ADDR_PREFIX "x"
75f3e8e4 Gabriel Somlo 2016-01-28 648
75f3e8e4 Gabriel Somlo 2016-01-28 649 #define PH_ADDR_PR_3_FMT PH_ADDR_PR_1_FMT \
75f3e8e4 Gabriel Somlo 2016-01-28 650 ":%" __PHYS_ADDR_PREFIX "u" \
75f3e8e4 Gabriel Somlo 2016-01-28 651 ":%" __PHYS_ADDR_PREFIX "u"
75f3e8e4 Gabriel Somlo 2016-01-28 652
46ebd6f8 Marc-André Lureau 2017-09-19 653 #define PH_ADDR_PR_4_FMT PH_ADDR_PR_3_FMT \
46ebd6f8 Marc-André Lureau 2017-09-19 654 ":%" __PHYS_ADDR_PREFIX "u"
46ebd6f8 Marc-André Lureau 2017-09-19 655
75f3e8e4 Gabriel Somlo 2016-01-28 656 static int fw_cfg_cmdline_set(const char *arg, const struct kernel_param *kp)
75f3e8e4 Gabriel Somlo 2016-01-28 657 {
46ebd6f8 Marc-André Lureau 2017-09-19 658 struct resource res[4] = {};
75f3e8e4 Gabriel Somlo 2016-01-28 659 char *str;
75f3e8e4 Gabriel Somlo 2016-01-28 660 phys_addr_t base;
46ebd6f8 Marc-André Lureau 2017-09-19 661 resource_size_t size, ctrl_off, data_off, dma_off;
75f3e8e4 Gabriel Somlo 2016-01-28 662 int processed, consumed = 0;
75f3e8e4 Gabriel Somlo 2016-01-28 663
75f3e8e4 Gabriel Somlo 2016-01-28 664 /* only one fw_cfg device can exist system-wide, so if one
75f3e8e4 Gabriel Somlo 2016-01-28 665 * was processed on the command line already, we might as
75f3e8e4 Gabriel Somlo 2016-01-28 666 * well stop here.
75f3e8e4 Gabriel Somlo 2016-01-28 667 */
75f3e8e4 Gabriel Somlo 2016-01-28 668 if (fw_cfg_cmdline_dev) {
75f3e8e4 Gabriel Somlo 2016-01-28 669 /* avoid leaking previously registered device */
75f3e8e4 Gabriel Somlo 2016-01-28 670 platform_device_unregister(fw_cfg_cmdline_dev);
75f3e8e4 Gabriel Somlo 2016-01-28 671 return -EINVAL;
75f3e8e4 Gabriel Somlo 2016-01-28 672 }
75f3e8e4 Gabriel Somlo 2016-01-28 673
75f3e8e4 Gabriel Somlo 2016-01-28 674 /* consume "<size>" portion of command line argument */
75f3e8e4 Gabriel Somlo 2016-01-28 675 size = memparse(arg, &str);
75f3e8e4 Gabriel Somlo 2016-01-28 676
46ebd6f8 Marc-André Lureau 2017-09-19 677 /* get "@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]" chunks */
75f3e8e4 Gabriel Somlo 2016-01-28 678 processed = sscanf(str, PH_ADDR_SCAN_FMT,
75f3e8e4 Gabriel Somlo 2016-01-28 679 &base, &consumed,
46ebd6f8 Marc-André Lureau 2017-09-19 680 &ctrl_off, &data_off, &consumed,
46ebd6f8 Marc-André Lureau 2017-09-19 681 &dma_off, &consumed);
75f3e8e4 Gabriel Somlo 2016-01-28 682
46ebd6f8 Marc-André Lureau 2017-09-19 683 /* sscanf() must process precisely 1, 3 or 4 chunks:
75f3e8e4 Gabriel Somlo 2016-01-28 684 * <base> is mandatory, optionally followed by <ctrl_off>
46ebd6f8 Marc-André Lureau 2017-09-19 685 * and <data_off>, and <dma_off>;
75f3e8e4 Gabriel Somlo 2016-01-28 686 * there must be no extra characters after the last chunk,
75f3e8e4 Gabriel Somlo 2016-01-28 687 * so str[consumed] must be '\0'.
75f3e8e4 Gabriel Somlo 2016-01-28 688 */
75f3e8e4 Gabriel Somlo 2016-01-28 @689 if (str[consumed] ||
46ebd6f8 Marc-André Lureau 2017-09-19 690 (processed != 1 && processed != 3 && process != 4))
75f3e8e4 Gabriel Somlo 2016-01-28 691 return -EINVAL;
75f3e8e4 Gabriel Somlo 2016-01-28 692
75f3e8e4 Gabriel Somlo 2016-01-28 693 res[0].start = base;
75f3e8e4 Gabriel Somlo 2016-01-28 694 res[0].end = base + size - 1;
75f3e8e4 Gabriel Somlo 2016-01-28 695 res[0].flags = !strcmp(kp->name, "mmio") ? IORESOURCE_MEM :
75f3e8e4 Gabriel Somlo 2016-01-28 696 IORESOURCE_IO;
75f3e8e4 Gabriel Somlo 2016-01-28 697
75f3e8e4 Gabriel Somlo 2016-01-28 698 /* insert register offsets, if provided */
75f3e8e4 Gabriel Somlo 2016-01-28 699 if (processed > 1) {
75f3e8e4 Gabriel Somlo 2016-01-28 700 res[1].name = "ctrl";
75f3e8e4 Gabriel Somlo 2016-01-28 701 res[1].start = ctrl_off;
75f3e8e4 Gabriel Somlo 2016-01-28 702 res[1].flags = IORESOURCE_REG;
75f3e8e4 Gabriel Somlo 2016-01-28 703 res[2].name = "data";
75f3e8e4 Gabriel Somlo 2016-01-28 704 res[2].start = data_off;
75f3e8e4 Gabriel Somlo 2016-01-28 705 res[2].flags = IORESOURCE_REG;
75f3e8e4 Gabriel Somlo 2016-01-28 706 }
46ebd6f8 Marc-André Lureau 2017-09-19 707 if (processed > 3) {
46ebd6f8 Marc-André Lureau 2017-09-19 708 res[3].name = "dma";
46ebd6f8 Marc-André Lureau 2017-09-19 709 res[3].start = dma_off;
46ebd6f8 Marc-André Lureau 2017-09-19 710 res[3].flags = IORESOURCE_REG;
46ebd6f8 Marc-André Lureau 2017-09-19 711 }
75f3e8e4 Gabriel Somlo 2016-01-28 712
75f3e8e4 Gabriel Somlo 2016-01-28 713 /* "processed" happens to nicely match the number of resources
75f3e8e4 Gabriel Somlo 2016-01-28 714 * we need to pass in to this platform device.
75f3e8e4 Gabriel Somlo 2016-01-28 715 */
75f3e8e4 Gabriel Somlo 2016-01-28 716 fw_cfg_cmdline_dev = platform_device_register_simple("fw_cfg",
75f3e8e4 Gabriel Somlo 2016-01-28 717 PLATFORM_DEVID_NONE, res, processed);
75f3e8e4 Gabriel Somlo 2016-01-28 718 if (IS_ERR(fw_cfg_cmdline_dev))
75f3e8e4 Gabriel Somlo 2016-01-28 719 return PTR_ERR(fw_cfg_cmdline_dev);
75f3e8e4 Gabriel Somlo 2016-01-28 720
75f3e8e4 Gabriel Somlo 2016-01-28 721 return 0;
75f3e8e4 Gabriel Somlo 2016-01-28 722 }
75f3e8e4 Gabriel Somlo 2016-01-28 723
:::::: The code at line 689 was first introduced by commit
:::::: 75f3e8e47f381074801d0034874d20c638d9e3d9 firmware: introduce sysfs driver for QEMU's fw_cfg device
:::::: TO: Gabriel Somlo <somlo@cmu.edu>
:::::: CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 26389 bytes --]
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH v2 2/4] fw_cfg: do DMA read operation
2017-09-19 11:58 [PATCH v2 0/4] fw_cfg: add DMA operations & etc/vmcoreinfo support marcandre.lureau
2017-09-19 11:58 ` [PATCH v2 1/4] fw_cfg: add DMA register marcandre.lureau
@ 2017-09-19 11:58 ` marcandre.lureau
2017-09-22 11:25 ` kbuild test robot
2017-09-19 11:58 ` [PATCH v2 3/4] fw_cfg: write vmcoreinfo details marcandre.lureau
2017-09-19 11:58 ` [PATCH v2 4/4] RFC: fw_cfg: add DMA write operation in sysfs marcandre.lureau
3 siblings, 1 reply; 10+ messages in thread
From: marcandre.lureau @ 2017-09-19 11:58 UTC (permalink / raw)
To: linux-kernel; +Cc: somlo, qemu-devel, mst, Marc-André Lureau
From: Marc-André Lureau <marcandre.lureau@redhat.com>
Modify fw_cfg_read_blob() to use DMA if the device supports it.
Return errors, because the operation may fail.
This is a proof-of-concept patch with some FIXME. It uses yield() to
wait for the memory to be cleared. Help on how to improve this is
welcome.
We may also want to switch all the *buf addresses to use only
kmalloc'ed buffer (instead of using stack/image addresses with
dma=false).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
drivers/firmware/qemu_fw_cfg.c | 132 +++++++++++++++++++++++++++++++++++------
1 file changed, 115 insertions(+), 17 deletions(-)
diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c
index 614037703530..a0e24fdf3ae5 100644
--- a/drivers/firmware/qemu_fw_cfg.c
+++ b/drivers/firmware/qemu_fw_cfg.c
@@ -33,6 +33,7 @@
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/ioport.h>
+#include <linux/dma-mapping.h>
MODULE_AUTHOR("Gabriel L. Somlo <somlo@cmu.edu>");
MODULE_DESCRIPTION("QEMU fw_cfg sysfs support");
@@ -43,12 +44,25 @@ MODULE_LICENSE("GPL");
#define FW_CFG_ID 0x01
#define FW_CFG_FILE_DIR 0x19
+#define FW_CFG_VERSION_DMA 0x02
+#define FW_CFG_DMA_CTL_ERROR 0x01
+#define FW_CFG_DMA_CTL_READ 0x02
+#define FW_CFG_DMA_CTL_SKIP 0x04
+#define FW_CFG_DMA_CTL_SELECT 0x08
+#define FW_CFG_DMA_CTL_WRITE 0x10
+
/* size in bytes of fw_cfg signature */
#define FW_CFG_SIG_SIZE 4
/* fw_cfg "file name" is up to 56 characters (including terminating nul) */
#define FW_CFG_MAX_FILE_PATH 56
+/* platform device for dma mapping */
+static struct device *dev;
+
+/* fw_cfg revision attribute, in /sys/firmware/qemu_fw_cfg top-level dir. */
+static u32 fw_cfg_rev;
+
/* fw_cfg file directory entry type */
struct fw_cfg_file {
u32 size;
@@ -57,6 +71,12 @@ struct fw_cfg_file {
char name[FW_CFG_MAX_FILE_PATH];
};
+struct fw_cfg_dma {
+ u32 control;
+ u32 length;
+ u64 address;
+} __packed;
+
/* fw_cfg device i/o register addresses */
static bool fw_cfg_is_mmio;
static phys_addr_t fw_cfg_p_base;
@@ -75,12 +95,73 @@ static inline u16 fw_cfg_sel_endianness(u16 key)
return fw_cfg_is_mmio ? cpu_to_be16(key) : cpu_to_le16(key);
}
+static inline bool fw_cfg_dma_enabled(void)
+{
+ return fw_cfg_rev & FW_CFG_VERSION_DMA && fw_cfg_reg_dma;
+}
+
+static ssize_t fw_cfg_dma_transfer(void *address, u32 length, u32 control)
+{
+ dma_addr_t dma_addr = 0;
+ struct fw_cfg_dma *d;
+ dma_addr_t dma;
+ ssize_t ret = length;
+ enum dma_data_direction dir =
+ (control & FW_CFG_DMA_CTL_READ ? DMA_FROM_DEVICE : 0);
+
+ if (address && length) {
+ dma_addr = dma_map_single(dev, address, length, dir);
+ if (dma_mapping_error(NULL, dma_addr)) {
+ WARN(1, "%s: failed to map address\n", __func__);
+ return -EFAULT;
+ }
+ }
+
+ d = kmalloc(sizeof(*d), GFP_KERNEL | GFP_DMA);
+ if (!d) {
+ ret = -ENOMEM;
+ goto end;
+ }
+
+ dma = dma_map_single(dev, d, sizeof(*d), DMA_BIDIRECTIONAL);
+ if (dma_mapping_error(NULL, dma)) {
+ WARN(1, "%s: failed to map fw_cfg_dma\n", __func__);
+ ret = -EFAULT;
+ goto end;
+ }
+
+ *d = (struct fw_cfg_dma) {
+ .address = cpu_to_be64(dma_addr),
+ .length = cpu_to_be32(length),
+ .control = cpu_to_be32(control)
+ };
+
+ iowrite32be(dma >> 32, fw_cfg_reg_dma);
+ iowrite32be(dma, fw_cfg_reg_dma + 4);
+ while (be32_to_cpu(d->control) & ~FW_CFG_DMA_CTL_ERROR)
+ yield(); /* FIXME: wait_event? */
+
+ if (be32_to_cpu(d->control) & FW_CFG_DMA_CTL_ERROR)
+ ret = -EIO;
+
+ dma_unmap_single(dev, dma, sizeof(*d), DMA_BIDIRECTIONAL);
+
+end:
+ kfree(d);
+ if (dma_addr)
+ dma_unmap_single(dev, dma_addr, length, dir);
+
+ return ret;
+}
+
/* read chunk of given fw_cfg blob (caller responsible for sanity-check) */
-static inline void fw_cfg_read_blob(u16 key,
- void *buf, loff_t pos, size_t count)
+static ssize_t fw_cfg_read_blob(u16 key,
+ void *buf, loff_t pos, size_t count,
+ bool dma)
{
u32 glk = -1U;
acpi_status status;
+ ssize_t ret = count;
/* If we have ACPI, ensure mutual exclusion against any potential
* device access by the firmware, e.g. via AML methods:
@@ -90,17 +171,36 @@ static inline void fw_cfg_read_blob(u16 key,
/* Should never get here */
WARN(1, "fw_cfg_read_blob: Failed to lock ACPI!\n");
memset(buf, 0, count);
- return;
+ return -EBUSY;
}
mutex_lock(&fw_cfg_dev_lock);
- iowrite16(fw_cfg_sel_endianness(key), fw_cfg_reg_ctrl);
- while (pos-- > 0)
- ioread8(fw_cfg_reg_data);
- ioread8_rep(fw_cfg_reg_data, buf, count);
+ if (dma && fw_cfg_dma_enabled()) {
+ if (pos == 0) {
+ ret = fw_cfg_dma_transfer(buf, count, key << 16
+ | FW_CFG_DMA_CTL_SELECT
+ | FW_CFG_DMA_CTL_READ);
+ } else {
+ iowrite16(fw_cfg_sel_endianness(key), fw_cfg_reg_ctrl);
+ ret = fw_cfg_dma_transfer(0, pos, FW_CFG_DMA_CTL_SKIP);
+ if (ret < 0)
+ goto end;
+ ret = fw_cfg_dma_transfer(buf, count,
+ FW_CFG_DMA_CTL_READ);
+ }
+ } else {
+ iowrite16(fw_cfg_sel_endianness(key), fw_cfg_reg_ctrl);
+ while (pos-- > 0)
+ ioread8(fw_cfg_reg_data);
+ ioread8_rep(fw_cfg_reg_data, buf, count);
+ }
+
+end:
mutex_unlock(&fw_cfg_dev_lock);
acpi_release_global_lock(glk);
+
+ return ret;
}
/* clean up fw_cfg device i/o */
@@ -192,7 +292,7 @@ static int fw_cfg_do_platform_probe(struct platform_device *pdev)
#endif
/* verify fw_cfg device signature */
- fw_cfg_read_blob(FW_CFG_SIGNATURE, sig, 0, FW_CFG_SIG_SIZE);
+ fw_cfg_read_blob(FW_CFG_SIGNATURE, sig, 0, FW_CFG_SIG_SIZE, false);
if (memcmp(sig, "QEMU", FW_CFG_SIG_SIZE) != 0) {
fw_cfg_io_cleanup();
return -ENODEV;
@@ -201,9 +301,6 @@ static int fw_cfg_do_platform_probe(struct platform_device *pdev)
return 0;
}
-/* fw_cfg revision attribute, in /sys/firmware/qemu_fw_cfg top-level dir. */
-static u32 fw_cfg_rev;
-
static ssize_t fw_cfg_showrev(struct kobject *k, struct attribute *a, char *buf)
{
return sprintf(buf, "%u\n", fw_cfg_rev);
@@ -351,8 +448,7 @@ static ssize_t fw_cfg_sysfs_read_raw(struct file *filp, struct kobject *kobj,
if (count > entry->f.size - pos)
count = entry->f.size - pos;
- fw_cfg_read_blob(entry->f.select, buf, pos, count);
- return count;
+ return fw_cfg_read_blob(entry->f.select, buf, pos, count, true);
}
static struct bin_attribute fw_cfg_sysfs_attr_raw = {
@@ -505,7 +601,7 @@ static int fw_cfg_register_dir_entries(void)
struct fw_cfg_file *dir;
size_t dir_size;
- fw_cfg_read_blob(FW_CFG_FILE_DIR, &count, 0, sizeof(count));
+ fw_cfg_read_blob(FW_CFG_FILE_DIR, &count, 0, sizeof(count), false);
count = be32_to_cpu(count);
dir_size = count * sizeof(struct fw_cfg_file);
@@ -513,7 +609,7 @@ static int fw_cfg_register_dir_entries(void)
if (!dir)
return -ENOMEM;
- fw_cfg_read_blob(FW_CFG_FILE_DIR, dir, sizeof(count), dir_size);
+ fw_cfg_read_blob(FW_CFG_FILE_DIR, dir, sizeof(count), dir_size, true);
for (i = 0; i < count; i++) {
dir[i].size = be32_to_cpu(dir[i].size);
@@ -544,9 +640,10 @@ static int fw_cfg_sysfs_probe(struct platform_device *pdev)
* one fw_cfg device exist system-wide, so if one was already found
* earlier, we might as well stop here.
*/
- if (fw_cfg_sel_ko)
+ if (dev)
return -EBUSY;
+ dev = &pdev->dev;
/* create by_key and by_name subdirs of /sys/firmware/qemu_fw_cfg/ */
err = -ENOMEM;
fw_cfg_sel_ko = kobject_create_and_add("by_key", fw_cfg_top_ko);
@@ -562,7 +659,7 @@ static int fw_cfg_sysfs_probe(struct platform_device *pdev)
goto err_probe;
/* get revision number, add matching top-level attribute */
- fw_cfg_read_blob(FW_CFG_ID, &fw_cfg_rev, 0, sizeof(fw_cfg_rev));
+ fw_cfg_read_blob(FW_CFG_ID, &fw_cfg_rev, 0, sizeof(fw_cfg_rev), false);
fw_cfg_rev = le32_to_cpu(fw_cfg_rev);
err = sysfs_create_file(fw_cfg_top_ko, &fw_cfg_rev_attr.attr);
if (err)
@@ -587,6 +684,7 @@ static int fw_cfg_sysfs_probe(struct platform_device *pdev)
err_name:
fw_cfg_kobj_cleanup(fw_cfg_sel_ko);
err_sel:
+ dev = NULL;
return err;
}
--
2.14.1.146.gd35faa819
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH v2 2/4] fw_cfg: do DMA read operation
2017-09-19 11:58 ` [PATCH v2 2/4] fw_cfg: do DMA read operation marcandre.lureau
@ 2017-09-22 11:25 ` kbuild test robot
0 siblings, 0 replies; 10+ messages in thread
From: kbuild test robot @ 2017-09-22 11:25 UTC (permalink / raw)
To: marcandre.lureau
Cc: kbuild-all, linux-kernel, somlo, qemu-devel, mst, Marc-André Lureau
[-- Attachment #1: Type: text/plain, Size: 7688 bytes --]
Hi Marc-André,
[auto build test WARNING on linus/master]
[also build test WARNING on v4.14-rc1 next-20170922]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/marcandre-lureau-redhat-com/fw_cfg-add-DMA-operations-etc-vmcoreinfo-support/20170922-182716
config: i386-randconfig-x000-201738 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All warnings (new ones prefixed by >>):
drivers//firmware/qemu_fw_cfg.c: In function 'fw_cfg_dma_transfer':
>> drivers//firmware/qemu_fw_cfg.c:139:18: warning: right shift count >= width of type [-Wshift-count-overflow]
iowrite32be(dma >> 32, fw_cfg_reg_dma);
^~
In file included from include/uapi/linux/stddef.h:1:0,
from include/linux/stddef.h:4,
from include/uapi/linux/posix_types.h:4,
from include/uapi/linux/types.h:13,
from include/linux/types.h:5,
from include/linux/list.h:4,
from include/linux/module.h:9,
from drivers//firmware/qemu_fw_cfg.c:30:
drivers//firmware/qemu_fw_cfg.c: At top level:
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'strcpy' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:421:2: note: in expansion of macro 'if'
if (p_size == (size_t)-1 && q_size == (size_t)-1)
^~
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'kmemdup' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:411:2: note: in expansion of macro 'if'
if (p_size < size)
^~
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'kmemdup' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:409:2: note: in expansion of macro 'if'
if (__builtin_constant_p(size) && p_size < size)
^~
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memchr_inv' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:400:2: note: in expansion of macro 'if'
if (p_size < size)
^~
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memchr_inv' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:398:2: note: in expansion of macro 'if'
if (__builtin_constant_p(size) && p_size < size)
^~
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memchr' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:389:2: note: in expansion of macro 'if'
if (p_size < size)
^~
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memchr' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:387:2: note: in expansion of macro 'if'
if (__builtin_constant_p(size) && p_size < size)
^~
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memcmp' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:379:2: note: in expansion of macro 'if'
if (p_size < size || q_size < size)
^~
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memcmp' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:376:3: note: in expansion of macro 'if'
if (q_size < size)
^~
include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memcmp' which is not static
______f = { \
^
include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
^~~~~~~~~~
include/linux/string.h:374:3: note: in expansion of macro 'if'
if (p_size < size)
vim +139 drivers//firmware/qemu_fw_cfg.c
102
103 static ssize_t fw_cfg_dma_transfer(void *address, u32 length, u32 control)
104 {
105 dma_addr_t dma_addr = 0;
106 struct fw_cfg_dma *d;
107 dma_addr_t dma;
108 ssize_t ret = length;
109 enum dma_data_direction dir =
110 (control & FW_CFG_DMA_CTL_READ ? DMA_FROM_DEVICE : 0);
111
112 if (address && length) {
113 dma_addr = dma_map_single(dev, address, length, dir);
114 if (dma_mapping_error(NULL, dma_addr)) {
115 WARN(1, "%s: failed to map address\n", __func__);
116 return -EFAULT;
117 }
118 }
119
120 d = kmalloc(sizeof(*d), GFP_KERNEL | GFP_DMA);
121 if (!d) {
122 ret = -ENOMEM;
123 goto end;
124 }
125
126 dma = dma_map_single(dev, d, sizeof(*d), DMA_BIDIRECTIONAL);
127 if (dma_mapping_error(NULL, dma)) {
128 WARN(1, "%s: failed to map fw_cfg_dma\n", __func__);
129 ret = -EFAULT;
130 goto end;
131 }
132
133 *d = (struct fw_cfg_dma) {
134 .address = cpu_to_be64(dma_addr),
135 .length = cpu_to_be32(length),
136 .control = cpu_to_be32(control)
137 };
138
> 139 iowrite32be(dma >> 32, fw_cfg_reg_dma);
140 iowrite32be(dma, fw_cfg_reg_dma + 4);
141 while (be32_to_cpu(d->control) & ~FW_CFG_DMA_CTL_ERROR)
142 yield(); /* FIXME: wait_event? */
143
144 if (be32_to_cpu(d->control) & FW_CFG_DMA_CTL_ERROR)
145 ret = -EIO;
146
147 dma_unmap_single(dev, dma, sizeof(*d), DMA_BIDIRECTIONAL);
148
149 end:
150 kfree(d);
151 if (dma_addr)
152 dma_unmap_single(dev, dma_addr, length, dir);
153
154 return ret;
155 }
156
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 29438 bytes --]
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH v2 3/4] fw_cfg: write vmcoreinfo details
2017-09-19 11:58 [PATCH v2 0/4] fw_cfg: add DMA operations & etc/vmcoreinfo support marcandre.lureau
2017-09-19 11:58 ` [PATCH v2 1/4] fw_cfg: add DMA register marcandre.lureau
2017-09-19 11:58 ` [PATCH v2 2/4] fw_cfg: do DMA read operation marcandre.lureau
@ 2017-09-19 11:58 ` marcandre.lureau
2017-09-22 18:01 ` kbuild test robot
2017-09-22 20:38 ` kbuild test robot
2017-09-19 11:58 ` [PATCH v2 4/4] RFC: fw_cfg: add DMA write operation in sysfs marcandre.lureau
3 siblings, 2 replies; 10+ messages in thread
From: marcandre.lureau @ 2017-09-19 11:58 UTC (permalink / raw)
To: linux-kernel; +Cc: somlo, qemu-devel, mst, Marc-André Lureau
From: Marc-André Lureau <marcandre.lureau@redhat.com>
If the "etc/vmcoreinfo" file is present, write the addr/size of the
vmcoreinfo ELF note.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
drivers/firmware/qemu_fw_cfg.c | 80 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 79 insertions(+), 1 deletion(-)
diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c
index a0e24fdf3ae5..26152bfc7805 100644
--- a/drivers/firmware/qemu_fw_cfg.c
+++ b/drivers/firmware/qemu_fw_cfg.c
@@ -34,6 +34,7 @@
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/dma-mapping.h>
+#include <linux/crash_core.h>
MODULE_AUTHOR("Gabriel L. Somlo <somlo@cmu.edu>");
MODULE_DESCRIPTION("QEMU fw_cfg sysfs support");
@@ -57,6 +58,8 @@ MODULE_LICENSE("GPL");
/* fw_cfg "file name" is up to 56 characters (including terminating nul) */
#define FW_CFG_MAX_FILE_PATH 56
+#define VMCOREINFO_FORMAT_ELF 0x1
+
/* platform device for dma mapping */
static struct device *dev;
@@ -107,7 +110,8 @@ static ssize_t fw_cfg_dma_transfer(void *address, u32 length, u32 control)
dma_addr_t dma;
ssize_t ret = length;
enum dma_data_direction dir =
- (control & FW_CFG_DMA_CTL_READ ? DMA_FROM_DEVICE : 0);
+ (control & FW_CFG_DMA_CTL_READ ? DMA_FROM_DEVICE : 0) |
+ (control & FW_CFG_DMA_CTL_WRITE ? DMA_TO_DEVICE : 0);
if (address && length) {
dma_addr = dma_map_single(dev, address, length, dir);
@@ -203,6 +207,46 @@ static ssize_t fw_cfg_read_blob(u16 key,
return ret;
}
+/* write chunk of given fw_cfg blob (caller responsible for sanity-check) */
+static ssize_t fw_cfg_write_blob(u16 key,
+ void *buf, loff_t pos, size_t count)
+{
+ u32 glk = -1U;
+ acpi_status status;
+ ssize_t ret = count;
+
+ /* If we have ACPI, ensure mutual exclusion against any potential
+ * device access by the firmware, e.g. via AML methods:
+ */
+ status = acpi_acquire_global_lock(ACPI_WAIT_FOREVER, &glk);
+ if (ACPI_FAILURE(status) && status != AE_NOT_CONFIGURED) {
+ /* Should never get here */
+ WARN(1, "%s: Failed to lock ACPI!\n", __func__);
+ memset(buf, 0, count);
+ return -EBUSY;
+ }
+
+ mutex_lock(&fw_cfg_dev_lock);
+ if (pos == 0) {
+ ret = fw_cfg_dma_transfer(buf, count, key << 16
+ | FW_CFG_DMA_CTL_SELECT
+ | FW_CFG_DMA_CTL_WRITE);
+ } else {
+ iowrite16(fw_cfg_sel_endianness(key), fw_cfg_reg_ctrl);
+ ret = fw_cfg_dma_transfer(0, pos, FW_CFG_DMA_CTL_SKIP);
+ if (ret < 0)
+ goto end;
+ ret = fw_cfg_dma_transfer(buf, count, FW_CFG_DMA_CTL_WRITE);
+ }
+
+end:
+ mutex_unlock(&fw_cfg_dev_lock);
+
+ acpi_release_global_lock(glk);
+
+ return ret;
+}
+
/* clean up fw_cfg device i/o */
static void fw_cfg_io_cleanup(void)
{
@@ -321,6 +365,35 @@ struct fw_cfg_sysfs_entry {
struct list_head list;
};
+static ssize_t write_vmcoreinfo(const struct fw_cfg_file *f)
+{
+ struct vmci {
+ __le16 host_format;
+ __le16 guest_format;
+ __le32 size;
+ __le64 paddr;
+ } __packed;
+ struct vmci *data;
+ ssize_t ret;
+
+ data = kmalloc(sizeof(struct vmci), GFP_KERNEL | GFP_DMA);
+ if (!data)
+ return -ENOMEM;
+
+ /* spare ourself reading host format support for now since we
+ * don't know what else to format - host may ignore ours
+ */
+ *data = (struct vmci) {
+ .guest_format = cpu_to_le16(VMCOREINFO_FORMAT_ELF),
+ .size = cpu_to_le32(VMCOREINFO_NOTE_SIZE),
+ .paddr = cpu_to_le64(paddr_vmcoreinfo_note())
+ };
+ ret = fw_cfg_write_blob(f->select, data, 0, sizeof(struct vmci));
+
+ kfree(data);
+ return ret;
+}
+
/* get fw_cfg_sysfs_entry from kobject member */
static inline struct fw_cfg_sysfs_entry *to_entry(struct kobject *kobj)
{
@@ -560,6 +633,11 @@ static int fw_cfg_register_file(const struct fw_cfg_file *f)
int err;
struct fw_cfg_sysfs_entry *entry;
+ if (strcmp(f->name, "etc/vmcoreinfo") == 0) {
+ if (write_vmcoreinfo(f) < 0)
+ pr_warn("fw_cfg: failed to write vmcoreinfo");
+ }
+
/* allocate new entry */
entry = kzalloc(sizeof(*entry), GFP_KERNEL);
if (!entry)
--
2.14.1.146.gd35faa819
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH v2 3/4] fw_cfg: write vmcoreinfo details
2017-09-19 11:58 ` [PATCH v2 3/4] fw_cfg: write vmcoreinfo details marcandre.lureau
@ 2017-09-22 18:01 ` kbuild test robot
2017-09-22 20:38 ` kbuild test robot
1 sibling, 0 replies; 10+ messages in thread
From: kbuild test robot @ 2017-09-22 18:01 UTC (permalink / raw)
To: marcandre.lureau
Cc: kbuild-all, linux-kernel, somlo, qemu-devel, mst, Marc-André Lureau
[-- Attachment #1: Type: text/plain, Size: 897 bytes --]
Hi Marc-André,
[auto build test ERROR on linus/master]
[also build test ERROR on v4.14-rc1 next-20170922]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/marcandre-lureau-redhat-com/fw_cfg-add-DMA-operations-etc-vmcoreinfo-support/20170922-182716
config: i386-randconfig-c0-09222256 (attached as .config)
compiler: gcc-4.9 (Debian 4.9.4-2) 4.9.4
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All errors (new ones prefixed by >>):
drivers/firmware/qemu_fw_cfg.o: In function `fw_cfg_register_dir_entries':
>> qemu_fw_cfg.c:(.text+0x8af): undefined reference to `paddr_vmcoreinfo_note'
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 31641 bytes --]
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH v2 3/4] fw_cfg: write vmcoreinfo details
2017-09-19 11:58 ` [PATCH v2 3/4] fw_cfg: write vmcoreinfo details marcandre.lureau
2017-09-22 18:01 ` kbuild test robot
@ 2017-09-22 20:38 ` kbuild test robot
1 sibling, 0 replies; 10+ messages in thread
From: kbuild test robot @ 2017-09-22 20:38 UTC (permalink / raw)
To: marcandre.lureau
Cc: kbuild-all, linux-kernel, somlo, qemu-devel, mst, Marc-André Lureau
[-- Attachment #1: Type: text/plain, Size: 831 bytes --]
Hi Marc-André,
[auto build test ERROR on linus/master]
[also build test ERROR on v4.14-rc1 next-20170922]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/marcandre-lureau-redhat-com/fw_cfg-add-DMA-operations-etc-vmcoreinfo-support/20170922-182716
config: x86_64-randconfig-ws0-09230003 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All errors (new ones prefixed by >>):
>> ERROR: "paddr_vmcoreinfo_note" [drivers/firmware/qemu_fw_cfg.ko] undefined!
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 28137 bytes --]
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH v2 4/4] RFC: fw_cfg: add DMA write operation in sysfs
2017-09-19 11:58 [PATCH v2 0/4] fw_cfg: add DMA operations & etc/vmcoreinfo support marcandre.lureau
` (2 preceding siblings ...)
2017-09-19 11:58 ` [PATCH v2 3/4] fw_cfg: write vmcoreinfo details marcandre.lureau
@ 2017-09-19 11:58 ` marcandre.lureau
3 siblings, 0 replies; 10+ messages in thread
From: marcandre.lureau @ 2017-09-19 11:58 UTC (permalink / raw)
To: linux-kernel; +Cc: somlo, qemu-devel, mst, Marc-André Lureau
From: Marc-André Lureau <marcandre.lureau@redhat.com>
Since qemu 2.9, DMA write operations are allowed. However, usage of this
interface from kernel or user-space is strongly discouraged by the
maintainers. This patch is meant for experimentations for now.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
drivers/firmware/qemu_fw_cfg.c | 21 ++++++++++++++++++++-
1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c
index 26152bfc7805..1ca3382e98df 100644
--- a/drivers/firmware/qemu_fw_cfg.c
+++ b/drivers/firmware/qemu_fw_cfg.c
@@ -524,9 +524,28 @@ static ssize_t fw_cfg_sysfs_read_raw(struct file *filp, struct kobject *kobj,
return fw_cfg_read_blob(entry->f.select, buf, pos, count, true);
}
+static ssize_t fw_cfg_sysfs_write_raw(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t pos, size_t count)
+{
+ struct fw_cfg_sysfs_entry *entry = to_entry(kobj);
+
+ if (!fw_cfg_dma_enabled())
+ return -ENOTSUPP;
+
+ if (pos > entry->f.size)
+ return -EINVAL;
+
+ if (count > entry->f.size - pos)
+ count = entry->f.size - pos;
+
+ return fw_cfg_write_blob(entry->f.select, buf, pos, count);
+}
+
static struct bin_attribute fw_cfg_sysfs_attr_raw = {
- .attr = { .name = "raw", .mode = S_IRUSR },
+ .attr = { .name = "raw", .mode = S_IRUSR | S_IWUSR },
.read = fw_cfg_sysfs_read_raw,
+ .write = fw_cfg_sysfs_write_raw,
};
/*
--
2.14.1.146.gd35faa819
^ permalink raw reply [flat|nested] 10+ messages in thread