Make the NVIC device expose a memory region for its users
to map, rather than mapping itself into the system memory
space on realize, and get the one user (the ARMv7M object)
to do this.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 1487604965-23220-7-git-send-email-peter.maydell@linaro.org

Make the ARMv7M object take a memory region link which it uses
to wire up the bitband rather than having them always put
themselves in the system address space.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 1487604965-23220-6-git-send-email-peter.maydell@linaro.org

Make the legacy armv7m_init() function use the newly QOMified
armv7m object rather than doing everything by hand.

We can return the armv7m object rather than the NVIC from
armv7m_init() because its interface to the rest of the
board (GPIOs, etc) is identical.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlistair Francis <alistair.francis@xilinx.com>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 1487604965-23220-5-git-send-email-peter.maydell@linaro.org

Create a proper QOM object for the armv7m container, which
holds the CPU, the NVIC and the bitband regions.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 1487604965-23220-4-git-send-email-peter.maydell@linaro.org

Move the NVICState struct definition into a header, so we can
embed it into other QOM objects like SoCs.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 1487604965-23220-3-git-send-email-peter.maydell@linaro.org

Abstract the "load kernel" code out of armv7m_init() into its own
function.  This includes the registration of the CPU reset function,
to parallel how we handle this for A profile cores.

We make the function public so that boards which choose to
directly instantiate an ARMv7M device object can call it.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NAlistair Francis <alistair.francis@xilinx.com>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 1487604965-23220-2-git-send-email-peter.maydell@linaro.org

target-arm queue:
 * raspi2: implement RNG module
 * raspi2: implement new SD card controller (but don't wire it up)
 * sdhci: bugfixes for block transfers
 * virt: fix cpu object reference leak
 * Add missing fp_access_check() to aarch64 crypto instructions
 * cputlb: Don't assume do_unassigned_access() never returns
 * virt: Add a user option to disallow ITS instantiation
 * i.MX timers: fix reset handling
 * ARMv7M NVIC: rewrite to fix broken priority handling and masking
 * exynos: Fix proper mapping of CPUs by providing real cluster ID
 * exynos: Fix Linux kernel division by zero for PLLs

# gpg: Signature made Tue 28 Feb 2017 12:40:51 GMT
# gpg:                using RSA key 0x3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20170228: (27 commits)
  hw/arm/exynos: Fix proper mapping of CPUs by providing real cluster ID
  hw/arm/exynos: Fix Linux kernel division by zero for PLLs
  bcm2835_sdhost: add bcm2835 sdhost controller
  armv7m: Allow SHCSR writes to change pending and active bits
  armv7m: Raise correct kind of UsageFault for attempts to execute ARM code
  armv7m: Check exception return consistency
  armv7m: Extract "exception taken" code into functions
  armv7m: VECTCLRACTIVE and VECTRESET are UNPREDICTABLE
  armv7m: Simpler and faster exception start
  armv7m: Remove unused armv7m_nvic_acknowledge_irq() return value
  armv7m: Escalate exceptions to HardFault if necessary
  arm: gic: Remove references to NVIC
  armv7m: Fix condition check for taking exceptions
  armv7m: Rewrite NVIC to not use any GIC code
  armv7m: Implement reading and writing of PRIGROUP
  armv7m: Rename nvic_state to NVICState
  ARM i.MX timers: fix reset handling
  hw/arm/virt: Add a user option to disallow ITS instantiation
  cputlb: Don't assume do_unassigned_access() never returns
  Add missing fp_access_check() to aarch64 crypto instructions
  ...
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

# gpg: Signature made Tue 28 Feb 2017 04:34:34 GMT
# gpg:                using RSA key 0xBDBE7B27C0DE3057
# gpg: Good signature from "Jeffrey Cody <jcody@redhat.com>"
# gpg:                 aka "Jeffrey Cody <jeff@codyprime.org>"
# gpg:                 aka "Jeffrey Cody <codyprime@gmail.com>"
# Primary key fingerprint: 9957 4B4D 3474 90E7 9D98  D624 BDBE 7B27 C0DE 3057

* remotes/cody/tags/block-pull-request:
  iscsi: add missing colons to the qapi docs
  block/mirror: fix broken sparseness detection
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Enable MTTCG for Alpha guest

# gpg: Signature made Tue 28 Feb 2017 00:43:17 GMT
# gpg:                using RSA key 0xAD1270CC4DD0279B
# gpg: Good signature from "Richard Henderson <rth7680@gmail.com>"
# gpg:                 aka "Richard Henderson <rth@redhat.com>"
# gpg:                 aka "Richard Henderson <rth@twiddle.net>"
# Primary key fingerprint: 9CB1 8DDA F8E8 49AD 2AFC  16A4 AD12 70CC 4DD0 279B

* remotes/rth/tags/pull-axp-20170228:
  target/alpha: Enable MTTCG by default
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The Exynos4210 has cluster ID 0x9 in its MPIDR register (raw value
0x8000090x).  If this cluster ID is not provided, then Linux kernel
cannot map DeviceTree nodes to MPIDR values resulting in kernel
warning and lack of any secondary CPUs:

    DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map
    ...
    smp: Bringing up secondary CPUs ...
    smp: Brought up 1 node, 1 CPU
    SMP: Total of 1 processors activated (24.00 BogoMIPS).

Provide a cluster ID so Linux will see proper MPIDR and will try to
bring the secondary CPU online.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Message-id: 20170226200142.31169-2-krzk@kernel.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Without any clock controller, the Linux kernel was hitting division by
zero during boot or with clk_summary:
[    0.000000] [<c031054c>] (unwind_backtrace) from [<c030ba6c>] (show_stack+0x10/0x14)
[    0.000000] [<c030ba6c>] (show_stack) from [<c05b2660>] (dump_stack+0x88/0x9c)
[    0.000000] [<c05b2660>] (dump_stack) from [<c05b11a4>] (Ldiv0+0x8/0x10)
[    0.000000] [<c05b11a4>] (Ldiv0) from [<c06ad1e0>] (samsung_pll45xx_recalc_rate+0x58/0x74)
[    0.000000] [<c06ad1e0>] (samsung_pll45xx_recalc_rate) from [<c0692ec0>] (clk_register+0x39c/0x63c)
[    0.000000] [<c0692ec0>] (clk_register) from [<c125d360>] (samsung_clk_register_pll+0x2e0/0x3d4)
[    0.000000] [<c125d360>] (samsung_clk_register_pll) from [<c125d7e8>] (exynos4_clk_init+0x1b0/0x5e4)
[    0.000000] [<c125d7e8>] (exynos4_clk_init) from [<c12335f4>] (of_clk_init+0x17c/0x210)
[    0.000000] [<c12335f4>] (of_clk_init) from [<c1204700>] (time_init+0x24/0x2c)
[    0.000000] [<c1204700>] (time_init) from [<c1200b2c>] (start_kernel+0x24c/0x38c)
[    0.000000] [<c1200b2c>] (start_kernel) from [<4020807c>] (0x4020807c)

Provide stub for clock controller returning reset values for PLLs.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Message-id: 20170226200142.31169-1-krzk@kernel.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This adds the BCM2835 SDHost controller from Arasan.
Signed-off-by: NClement Deschamps <clement.deschamps@antfield.fr>
Message-id: 20170224164021.9066-2-clement.deschamps@antfield.fr
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Implement the NVIC SHCSR write behaviour which allows pending and
active status of some exceptions to be changed.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

M profile doesn't implement ARM, and the architecturally required
behaviour for attempts to execute with the Thumb bit clear is to
generate a UsageFault with the CFSR INVSTATE bit set.  We were
incorrectly implementing this as generating an UNDEFINSTR UsageFault;
fix this.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

Implement the exception return consistency checks
described in the v7M pseudocode ExceptionReturn().

Inspired by a patch from Michael Davidsaver's series, but
this is a reimplementation from scratch based on the
ARM ARM pseudocode.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

Extract the code from the tail end of arm_v7m_do_interrupt() which
enters the exception handler into a pair of utility functions
v7m_exception_taken() and v7m_push_stack(), which correspond roughly
to the pseudocode PushStack() and ExceptionTaken().

This also requires us to move the arm_v7m_load_vector() utility
routine up so we can call it.

Handling illegal exception returns has some cases where we want to
take a UsageFault either on an existing stack frame or with a new
stack frame but with a specific LR value, so we want to be able to
call these without having to go via arm_v7m_cpu_do_interrupt().
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

The VECTCLRACTIVE and VECTRESET bits in the AIRCR are both
documented as UNPREDICTABLE if you write a 1 to them when
the processor is not halted in Debug state (ie stopped
and under the control of an external JTAG debugger).
Since we don't implement Debug state or emulated JTAG
these bits are always UNPREDICTABLE for us. Instead of
logging them as unimplemented we can simply log writes
as guest errors and ignore them.
Signed-off-by: NMichael Davidsaver <mdavidsaver@gmail.com>
[PMM: change extracted from another patch; commit message
 constructed from scratch]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

All the places in armv7m_cpu_do_interrupt() which pend an
exception in the NVIC are doing so for synchronous
exceptions. We know that we will always take some
exception in this case, so we can just acknowledge it
immediately, rather than returning and then immediately
being called again because the NVIC has raised its outbound
IRQ line.
Signed-off-by: NMichael Davidsaver <mdavidsaver@gmail.com>
[PMM: tweaked commit message; added DEBUG to the set of
exceptions we handle immediately, since it is synchronous
when it results from the BKPT instruction]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

Having armv7m_nvic_acknowledge_irq() return the new value of
env->v7m.exception and its one caller assign the return value
back to env->v7m.exception is pointless. Just make the return
type void instead.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

The v7M exception architecture requires that if a synchronous
exception cannot be taken immediately (because it is disabled
or at too low a priority) then it should be escalated to
HardFault (and the HardFault exception is then taken).
Implement this escalation logic.
Signed-off-by: NMichael Davidsaver <mdavidsaver@gmail.com>
[PMM: extracted from another patch]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

Now that the NVIC is its own separate implementation, we can
clean up the GIC code by removing REV_NVIC and conditionals
which use it.
Signed-off-by: NMichael Davidsaver <mdavidsaver@gmail.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

The M profile condition for when we can take a pending exception or
interrupt is not the same as that for A/R profile.  The code
originally copied from the A/R profile version of the
cpu_exec_interrupt function only worked by chance for the
very simple case of exceptions being masked by PRIMASK.
Replace it with a call to a function in the NVIC code that
correctly compares the priority of the pending exception
against the current execution priority of the CPU.

[Michael Davidsaver's patchset had a patch to do something
similar but the implementation ended up being a rewrite.]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

Despite some superficial similarities of register layout, the
M-profile NVIC is really very different from the A-profile GIC.
Our current attempt to reuse the GIC code means that we have
significant bugs in our NVIC.

Implement the NVIC as an entirely separate device, to give
us somewhere we can get the behaviour correct.

This initial commit does not attempt to implement exception
priority escalation, since the GIC-based code didn't either.
It does fix a few bugs in passing:
 * ICSR.RETTOBASE polarity was wrong and didn't account for
   internal exceptions
 * ICSR.VECTPENDING was 16 too high if the pending exception
   was for an external interrupt
 * UsageFault, BusFault and MemFault were not disabled on reset
   as they are supposed to be
Signed-off-by: NMichael Davidsaver <mdavidsaver@gmail.com>
[PMM: reworked, various bugs and stylistic cleanups]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

Add a state field for the v7M PRIGROUP register and implent
reading and writing it. The current NVIC doesn't honour
the values written, but the new version will.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

Rename the nvic_state struct to NVICState, to match
our naming conventions.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>

The i.MX timer device can be reset by writing to the SWR bit
of the CR register. This has to behave differently from hard
(power-on) reset because it does not reset all of the bits
in the CR register.

We were incorrectly implementing soft reset and hard reset
the same way, and in addition had a logic error which meant
that we were clearing the bits that soft-reset is supposed
to preserve and not touching the bits that soft-reset clears.
This was not correct behaviour for either kind of reset.

Separate out the soft reset and hard reset code paths, and
correct the handling of reset of the CR register so that it
is correct in both cases.
Signed-off-by: NKurban Mallachiev <mallachiev@ispras.ru>
[PMM: rephrased commit message, spacing on operators;
 use bool rather than int for is_soft_reset]
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In 2.9 ITS will block save/restore and migration use cases. As such,
let's introduce a user option that allows to turn its instantiation
off, along with GICv3. With the "its" option turned false, migration
will be possible, obviously at the expense of MSI support (with GICv3).
Signed-off-by: NEric Auger <eric.auger@redhat.com>
Message-id: 1487681108-14452-1-git-send-email-eric.auger@redhat.com
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In get_page_addr_code(), if the guest PC doesn't correspond to RAM
then we currently run the CPU's do_unassigned_access() hook if it has
one, and otherwise we give up and exit QEMU with a more-or-less
useful message.  This code assumes that the do_unassigned_access hook
will never return, because if it does then we'll plough on attempting
to use a non-RAM TLB entry to get a RAM address and will abort() in
qemu_ram_addr_from_host_nofail().  Unfortunately some CPU
implementations of this hook do return: Microblaze, SPARC and the ARM
v7M.

Change the code to call report_bad_exec() if the hook returns, as
well as if it didn't have one.  This means we can tidy it up to use
the cpu_unassigned_access() function which wraps the "get the CPU
class and call the hook if it has one" work, since we aren't trying
to distinguish "no hook" from "hook existed and returned" any more.

This brings the handling of this hook into line with the handling
used for data accesses, where "hook returned" is treated the
same as "no hook existed" and gets you the default behaviour.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

The aarch64 crypto instructions for AES and SHA are missing the
check for if the FPU is enabled.
Signed-off-by: NNick Reilly <nreilly@blackberry.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

object_new(FOO) returns an object with ref_cnt == 1
and following
  object_property_set_bool(cpuobj, true, "realized", NULL)
set parent of cpuobj to '/machine/unattached' which makes
ref_cnt == 2.

Since machvirt_init() doesn't take ownership of cpuobj
returned by object_new() it should explicitly drop
reference to cpuobj when dangling pointer is about to
go out of scope like it's done pc_new_cpu() to avoid
object leak.
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Message-id: 1487253461-269218-1-git-send-email-imammedo@redhat.com
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In SDHCI protocol, the 'Block count enable' bit of the Transfer
Mode register is relevant only in multi block transfers. We need
not check it in single block transfers.
Signed-off-by: NPrasad J Pandit <pjp@fedoraproject.org>
Message-id: 20170214185225.7994-5-ppandit@redhat.com
Reviewed-by: NAlistair Francis <alistair.francis@xilinx.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In sdhci_write invoke multi block transfer if it is enabled
in the transfer mode register 's->trnmod'.
Signed-off-by: NPrasad J Pandit <pjp@fedoraproject.org>
Message-id: 20170214185225.7994-4-ppandit@redhat.com
Reviewed-by: NAlistair Francis <alistair.francis@xilinx.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In the SDHCI protocol, the transfer mode register value
is used during multi block transfer to check if block count
register is enabled and should be updated. Transfer mode
register could be set such that, block count register would
not be updated, thus leading to an infinite loop. Add check
to avoid it.
Reported-by: NWjjzhang <wjjzhang@tencent.com>
Reported-by: NJiang Xin <jiangxin1@huawei.com>
Signed-off-by: NPrasad J Pandit <pjp@fedoraproject.org>
Message-id: 20170214185225.7994-3-ppandit@redhat.com
Reviewed-by: NAlistair Francis <alistair.francis@xilinx.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In SDHCI protocol, the transfer mode register is defined
to be of 6 bits. Mask its value with '0x0037' so that an
invalid value could not be assigned.
Signed-off-by: NPrasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: NAlistair Francis <alistair.francis@xilinx.com>
Message-id: 20170214185225.7994-2-ppandit@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Switch to using qcrypto_random_bytes() rather than rand() as
our source of randomness for the BCM2835 RNG.

If qcrypto_random_bytes() fails, we don't want to return the guest a
non-random value in case they're really using it for cryptographic
purposes, so the best we can do is a fatal error.  This shouldn't
happen unless something's broken, though.

In theory we could implement this device's full FIFO and interrupt
semantics and then just stop filling the FIFO.  That's a lot of work,
though, and doesn't really give a very nice diagnostic to the user
since the guest will just seem to hang.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NDaniel P. Berrange <berrange@redhat.com>

Recent vanilla Raspberry Pi kernels started to make use of
the hardware random number generator in BCM2835 SoC. As a
result, those kernels wouldn't work anymore under QEMU
but rather just freeze during the boot process.

This patch implements a trivial BCM2835 compatible RNG,
and adds it as a peripheral to BCM2835 platform, which
allows to boot a vanilla Raspberry Pi kernel under Qemu.

Changes since v1:
 * Prevented guest from writing [31..20] bits in rng_status
 * Removed redundant minimum_version_id_old
 * Added field entries for the state
 * Changed realize function to reset
Signed-off-by: NMarcin Chojnacki <marcinch7@gmail.com>
Message-id: 20170210210857.47893-1-marcinch7@gmail.com
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Merge remote-tracking branch 'remotes/vivier2/tags/linux-user-for-upstream-pull-request' into staging

# gpg: Signature made Mon 27 Feb 2017 22:15:47 GMT
# gpg:                using RSA key 0xF30C38BD3F2FBE3C
# gpg: Good signature from "Laurent Vivier <lvivier@redhat.com>"
# gpg:                 aka "Laurent Vivier <laurent@vivier.eu>"
# gpg:                 aka "Laurent Vivier (Red Hat) <lvivier@redhat.com>"
# Primary key fingerprint: CD2F 75DD C8E3 A4DC 2E4F  5173 F30C 38BD 3F2F BE3C

* remotes/vivier2/tags/linux-user-for-upstream-pull-request:
  syscall: fixed mincore(2) not failing with ENOMEM
  linux-user: fix do_rt_sigreturn on m68k linux userspace emulation
  linux-user: correctly manage SR in ucontext
  linux-user: Add signal handling support for x86_64
  linux-user: Add sockopts for IPv6 ping and IPv6 traceroute
  linux-user: fix fork()
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

# gpg: Signature made Mon 27 Feb 2017 16:33:23 GMT
# gpg:                using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
  tests-aio-multithread: use atomic_read properly
  iscsi: do not use aio_context_acquire/release
  nfs: do not use aio_context_acquire/release
  curl: do not use aio_context_acquire/release
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The missing colons make the iscsi part of the documentation not render
quite as nicely, so add those in.
Signed-off-by: NJeff Cody <jcody@redhat.com>

Alpha has a weak memory ordering and issues all of the required barriers.
Signed-off-by: NRichard Henderson <rth@twiddle.net>