qemu/hw/input/milkymist-softusb.c
Markus Armbruster f8ed85ac99 Fix bad error handling after memory_region_init_ram()
Symptom:

    $ qemu-system-x86_64 -m 10000000
    Unexpected error in ram_block_add() at /work/armbru/qemu/exec.c:1456:
    upstream-qemu: cannot set up guest memory 'pc.ram': Cannot allocate memory
    Aborted (core dumped)

Root cause: commit ef701d7 screwed up handling of out-of-memory
conditions.  Before the commit, we report the error and exit(1), in
one place, ram_block_add().  The commit lifts the error handling up
the call chain some, to three places.  Fine.  Except it uses
&error_abort in these places, changing the behavior from exit(1) to
abort(), and thus undoing the work of commit 3922825 "exec: Don't
abort when we can't allocate guest memory".

The three places are:

* memory_region_init_ram()

  Commit 4994653 (right after commit ef701d7) lifted the error
  handling further, through memory_region_init_ram(), multiplying the
  incorrect use of &error_abort.  Later on, imitation of existing
  (bad) code may have created more.

* memory_region_init_ram_ptr()

  The &error_abort is still there.

* memory_region_init_rom_device()

  Doesn't need fixing, because commit 33e0eb5 (soon after commit
  ef701d7) lifted the error handling further, and in the process
  changed it from &error_abort to passing it up the call chain.
  Correct, because the callers are realize() methods.

Fix the error handling after memory_region_init_ram() with a
Coccinelle semantic patch:

    @r@
    expression mr, owner, name, size, err;
    position p;
    @@
            memory_region_init_ram(mr, owner, name, size,
    (
    -                              &error_abort
    +                              &error_fatal
    |
                                   err@p
    )
                                  );
    @script:python@
        p << r.p;
    @@
    print "%s:%s:%s" % (p[0].file, p[0].line, p[0].column)

When the last argument is &error_abort, it gets replaced by
&error_fatal.  This is the fix.

If the last argument is anything else, its position is reported.  This
lets us check the fix is complete.  Four positions get reported:

* ram_backend_memory_alloc()

  Error is passed up the call chain, ultimately through
  user_creatable_complete().  As far as I can tell, it's callers all
  handle the error sanely.

* fsl_imx25_realize(), fsl_imx31_realize(), dp8393x_realize()

  DeviceClass.realize() methods, errors handled sanely further up the
  call chain.

We're good.  Test case again behaves:

    $ qemu-system-x86_64 -m 10000000
    qemu-system-x86_64: cannot set up guest memory 'pc.ram': Cannot allocate memory
    [Exit 1 ]

The next commits will repair the rest of commit ef701d7's damage.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1441983105-26376-3-git-send-email-armbru@redhat.com>
Reviewed-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
2015-09-18 14:39:29 +02:00

318 lines
8.4 KiB
C

/*
* QEMU model of the Milkymist SoftUSB block.
*
* Copyright (c) 2010 Michael Walle <michael@walle.cc>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
*
* Specification available at:
* not available yet
*/
#include "hw/hw.h"
#include "hw/sysbus.h"
#include "trace.h"
#include "ui/console.h"
#include "hw/input/hid.h"
#include "qemu/error-report.h"
enum {
R_CTRL = 0,
R_MAX
};
enum {
CTRL_RESET = (1<<0),
};
#define COMLOC_DEBUG_PRODUCE 0x1000
#define COMLOC_DEBUG_BASE 0x1001
#define COMLOC_MEVT_PRODUCE 0x1101
#define COMLOC_MEVT_BASE 0x1102
#define COMLOC_KEVT_PRODUCE 0x1142
#define COMLOC_KEVT_BASE 0x1143
#define TYPE_MILKYMIST_SOFTUSB "milkymist-softusb"
#define MILKYMIST_SOFTUSB(obj) \
OBJECT_CHECK(MilkymistSoftUsbState, (obj), TYPE_MILKYMIST_SOFTUSB)
struct MilkymistSoftUsbState {
SysBusDevice parent_obj;
HIDState hid_kbd;
HIDState hid_mouse;
MemoryRegion regs_region;
MemoryRegion pmem;
MemoryRegion dmem;
qemu_irq irq;
void *pmem_ptr;
void *dmem_ptr;
/* device properties */
uint32_t pmem_size;
uint32_t dmem_size;
/* device registers */
uint32_t regs[R_MAX];
/* mouse state */
uint8_t mouse_hid_buffer[4];
/* keyboard state */
uint8_t kbd_hid_buffer[8];
};
typedef struct MilkymistSoftUsbState MilkymistSoftUsbState;
static uint64_t softusb_read(void *opaque, hwaddr addr,
unsigned size)
{
MilkymistSoftUsbState *s = opaque;
uint32_t r = 0;
addr >>= 2;
switch (addr) {
case R_CTRL:
r = s->regs[addr];
break;
default:
error_report("milkymist_softusb: read access to unknown register 0x"
TARGET_FMT_plx, addr << 2);
break;
}
trace_milkymist_softusb_memory_read(addr << 2, r);
return r;
}
static void
softusb_write(void *opaque, hwaddr addr, uint64_t value,
unsigned size)
{
MilkymistSoftUsbState *s = opaque;
trace_milkymist_softusb_memory_write(addr, value);
addr >>= 2;
switch (addr) {
case R_CTRL:
s->regs[addr] = value;
break;
default:
error_report("milkymist_softusb: write access to unknown register 0x"
TARGET_FMT_plx, addr << 2);
break;
}
}
static const MemoryRegionOps softusb_mmio_ops = {
.read = softusb_read,
.write = softusb_write,
.endianness = DEVICE_NATIVE_ENDIAN,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
};
static inline void softusb_read_dmem(MilkymistSoftUsbState *s,
uint32_t offset, uint8_t *buf, uint32_t len)
{
if (offset + len >= s->dmem_size) {
error_report("milkymist_softusb: read dmem out of bounds "
"at offset 0x%x, len %d", offset, len);
memset(buf, 0, len);
return;
}
memcpy(buf, s->dmem_ptr + offset, len);
}
static inline void softusb_write_dmem(MilkymistSoftUsbState *s,
uint32_t offset, uint8_t *buf, uint32_t len)
{
if (offset + len >= s->dmem_size) {
error_report("milkymist_softusb: write dmem out of bounds "
"at offset 0x%x, len %d", offset, len);
return;
}
memcpy(s->dmem_ptr + offset, buf, len);
}
static void softusb_mouse_changed(MilkymistSoftUsbState *s)
{
uint8_t m;
softusb_read_dmem(s, COMLOC_MEVT_PRODUCE, &m, 1);
trace_milkymist_softusb_mevt(m);
softusb_write_dmem(s, COMLOC_MEVT_BASE + 4 * m, s->mouse_hid_buffer, 4);
m = (m + 1) & 0xf;
softusb_write_dmem(s, COMLOC_MEVT_PRODUCE, &m, 1);
trace_milkymist_softusb_pulse_irq();
qemu_irq_pulse(s->irq);
}
static void softusb_kbd_changed(MilkymistSoftUsbState *s)
{
uint8_t m;
softusb_read_dmem(s, COMLOC_KEVT_PRODUCE, &m, 1);
trace_milkymist_softusb_kevt(m);
softusb_write_dmem(s, COMLOC_KEVT_BASE + 8 * m, s->kbd_hid_buffer, 8);
m = (m + 1) & 0x7;
softusb_write_dmem(s, COMLOC_KEVT_PRODUCE, &m, 1);
trace_milkymist_softusb_pulse_irq();
qemu_irq_pulse(s->irq);
}
static void softusb_kbd_hid_datain(HIDState *hs)
{
MilkymistSoftUsbState *s = container_of(hs, MilkymistSoftUsbState, hid_kbd);
int len;
/* if device is in reset, do nothing */
if (s->regs[R_CTRL] & CTRL_RESET) {
return;
}
while (hid_has_events(hs)) {
len = hid_keyboard_poll(hs, s->kbd_hid_buffer,
sizeof(s->kbd_hid_buffer));
if (len == 8) {
softusb_kbd_changed(s);
}
}
}
static void softusb_mouse_hid_datain(HIDState *hs)
{
MilkymistSoftUsbState *s =
container_of(hs, MilkymistSoftUsbState, hid_mouse);
int len;
/* if device is in reset, do nothing */
if (s->regs[R_CTRL] & CTRL_RESET) {
return;
}
while (hid_has_events(hs)) {
len = hid_pointer_poll(hs, s->mouse_hid_buffer,
sizeof(s->mouse_hid_buffer));
if (len == 4) {
softusb_mouse_changed(s);
}
}
}
static void milkymist_softusb_reset(DeviceState *d)
{
MilkymistSoftUsbState *s = MILKYMIST_SOFTUSB(d);
int i;
for (i = 0; i < R_MAX; i++) {
s->regs[i] = 0;
}
memset(s->kbd_hid_buffer, 0, sizeof(s->kbd_hid_buffer));
memset(s->mouse_hid_buffer, 0, sizeof(s->mouse_hid_buffer));
hid_reset(&s->hid_kbd);
hid_reset(&s->hid_mouse);
/* defaults */
s->regs[R_CTRL] = CTRL_RESET;
}
static int milkymist_softusb_init(SysBusDevice *dev)
{
MilkymistSoftUsbState *s = MILKYMIST_SOFTUSB(dev);
sysbus_init_irq(dev, &s->irq);
memory_region_init_io(&s->regs_region, OBJECT(s), &softusb_mmio_ops, s,
"milkymist-softusb", R_MAX * 4);
sysbus_init_mmio(dev, &s->regs_region);
/* register pmem and dmem */
memory_region_init_ram(&s->pmem, OBJECT(s), "milkymist-softusb.pmem",
s->pmem_size, &error_fatal);
vmstate_register_ram_global(&s->pmem);
s->pmem_ptr = memory_region_get_ram_ptr(&s->pmem);
sysbus_init_mmio(dev, &s->pmem);
memory_region_init_ram(&s->dmem, OBJECT(s), "milkymist-softusb.dmem",
s->dmem_size, &error_fatal);
vmstate_register_ram_global(&s->dmem);
s->dmem_ptr = memory_region_get_ram_ptr(&s->dmem);
sysbus_init_mmio(dev, &s->dmem);
hid_init(&s->hid_kbd, HID_KEYBOARD, softusb_kbd_hid_datain);
hid_init(&s->hid_mouse, HID_MOUSE, softusb_mouse_hid_datain);
return 0;
}
static const VMStateDescription vmstate_milkymist_softusb = {
.name = "milkymist-softusb",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT32_ARRAY(regs, MilkymistSoftUsbState, R_MAX),
VMSTATE_HID_KEYBOARD_DEVICE(hid_kbd, MilkymistSoftUsbState),
VMSTATE_HID_POINTER_DEVICE(hid_mouse, MilkymistSoftUsbState),
VMSTATE_BUFFER(kbd_hid_buffer, MilkymistSoftUsbState),
VMSTATE_BUFFER(mouse_hid_buffer, MilkymistSoftUsbState),
VMSTATE_END_OF_LIST()
}
};
static Property milkymist_softusb_properties[] = {
DEFINE_PROP_UINT32("pmem_size", MilkymistSoftUsbState, pmem_size, 0x00001000),
DEFINE_PROP_UINT32("dmem_size", MilkymistSoftUsbState, dmem_size, 0x00002000),
DEFINE_PROP_END_OF_LIST(),
};
static void milkymist_softusb_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
k->init = milkymist_softusb_init;
dc->reset = milkymist_softusb_reset;
dc->vmsd = &vmstate_milkymist_softusb;
dc->props = milkymist_softusb_properties;
}
static const TypeInfo milkymist_softusb_info = {
.name = TYPE_MILKYMIST_SOFTUSB,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(MilkymistSoftUsbState),
.class_init = milkymist_softusb_class_init,
};
static void milkymist_softusb_register_types(void)
{
type_register_static(&milkymist_softusb_info);
}
type_init(milkymist_softusb_register_types)