linux-user/signal.c: Correct error path for AArch64 do_rt_sigreturn

The error path in AArch64 do_rt_sigreturn() which fails before
attempting lock_user_struct() was doing an unlock_user_struct()
on an uninitialized variable. Initialize frame to NULL so we
can use the same error-exit path in all cases (unlock of NULL
is permitted and does nothing).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
linux-user: Don't return uninitialized value for atomic_barrier syscall

QEMU's implementation of the m68k atomic_barrier syscall, like the kernel's,
is just a no-op. However we still need to return a result code from it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
linux-user: implement F_[GS]ETOWN_EX

F_GETOWN is replaced by F_GETOWN_EX inside the glibc fcntl wrapper

Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
linux-user: Don't reserve space for commpage for AArch64

AArch64 Linux, unlike AArch32, doesn't use a commpage. This means we
should not be reserving room in the guest address space for one.
Fixes LP:1287195.

Reported-by: Amanieu d'Antras <amanieu@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
signal: added a wrapper for sigprocmask function

Create a wrapper for signal mask changes initiated by the guest;
(this includes syscalls and also the sigreturns from signal.c)
this will give us a place to put code which prevents the guest
from changing the handling of signals used by QEMU itself
internally.

The wrapper is called from all the guest-initiated sigprocmask, but
is not called from internal qemu sigprocmask calls.

Signed-off-by: Alex Barcelo <abarcelo@ac.upc.edu>
[PMM: Added calls to wrapper for sigprocmask uses in signal.c
when setting the signal mask on entry and exit from signal
handlers, since these also are guest-provided signal masks.]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
linux-user: Don't allow guest to block SIGSEGV

Don't allow the linux-user guest to block SIGSEGV -- QEMU needs this
signal to detect accesses to pages which it has marked read-only
because it has cached translated code from them.

We implement this by making the do_sigprocmask() wrapper suppress
SIGSEGV when doing the host process signal mask manipulation; instead
we store the current state of SIGSEGV in the TaskState struct.

If we get a SIGSEGV for the guest when the guest has blocked the
signal, we treat it as if the default SEGV handler was in place,
as the kernel does for forced SIGSEGV delivery.

This patch is based on an idea by Alex Barcelo, but rather than
simply lying to the guest about the SIGSEGV state we track it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reported-by: Alex Barcelo <abarcelo@ac.upc.edu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
linux-user: Implement capget, capset

Implement the capget and capset syscalls. This is useful because
simple programs like 'ls' try to use it in AArch64, and otherwise
we emit a lot of noise about it being unimplemented.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
ahci: fix sysbus support

Non-PCI AHCI support is broken due to assertion failures when trying
to convert AHCIState to a PCIDevice pointer as AHCIState can have
different container structs. Fix this by using the non-asserting object
cast and checking the returned pointer is not NULL.

The AddressSpace pointer is also being initialized to NULL and causing
dma_memory_map call to fail. Fix this by initializing to
address_space_memory for sysbus instances.

Also correct AHCI_VMSTATE to use the correct container SysbusAHCIState
for sysbus instances.

Signed-off-by: Rob Herring <rob.herring@linaro.org>
Message-id: 1392073373-3295-1-git-send-email-robherring2@gmail.com
[PMM: added linebreaks to fix overlong lines]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
pl011: reset the fifo when enabled or disabled

Intermittent issues have been seen where no serial input occurs. It
appears the pl011 gets in a state where the rx interrupt never fires
because the rx interrupt only asserts when crossing the fifo trigger
level. The fifo state appears to get out of sync when the pl011 is
re-configured. This combined with the rx timeout interrupt not being
modeled results in no more rx interrupts.

Disabling the fifo is the recommended way to clear the tx fifo in the
TRM (section 3.3.8). The behavior in this case for the rx fifo is
undefined in the TRM, but having fifo contents to be maintained during
configuration changes is not likely expected behavior. Reseting the
fifo state when the fifo size is changed is the simplest solution.

Signed-off-by: Rob Herring <rob.herring@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1395166721-15716-2-git-send-email-robherring2@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
pl011: fix UARTRSR accesses corrupting the UARTCR value

Offset 4 is UARTRSR/UARTECR, not the UARTCR. The UARTCR would be
corrupted if the UARTRSR is ever written. Fix by implementing a correct
model of the UARTRSR/UARTECR register. Reads of this register simply
reflect the error bits in data register. Only breaks can be triggered in
QEMU. With the pl011_can_receive function, we effectively have flow
control between the host and the model. Framing and parity errors simply
don't make sense in the model and will never occur.

Signed-off-by: Rob Herring <rob.herring@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1395166721-15716-3-git-send-email-robherring2@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
pl011: fix incorrect logic to set the RXFF flag

The receive fifo full bit should be set when 1 character is received and
the fifo is disabled or when 16 characters are in the fifo.

Signed-off-by: Rob Herring <rob.herring@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1395166721-15716-4-git-send-email-robherring2@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
target-arm: A64: Add saturating int ops (SQNEG/SQABS)

This mostly re-uses the existing NEON helpers with an additional two for
the 64 bit case. I also took the opportunity to add TCG_CALL_NO_RWG
options to the helpers as they don't modify globals (saturation flags
are in the CPU Environment).

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
target-arm: A64: Add saturating accumulate ops (USQADD/SUQADD)

Add the saturating accumulate operations USQADD and SUQADD
to the A64 instruction set. This completes coverage of A64 Neon.
These operations (which are unsigned + signed -> signed and
signed + unsigned -> unsigned) don't exist in the A32/T32
instruction set, so require a complete new set of helper functions.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
block: Add error handling to bdrv_invalidate_cache()

If it returns an error, the migrated VM will not be started, but qemu
exits with an error message.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
qemu-io-cmds: Fixed typo in example for writev.

Signed-off-by: Maria Kustova <maria.k@catit.be>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
qemu-io: Extended "--cmd" description in usage text

It's not clear from the usage description that "--cmd" option accepts
its argument as a string, so any special symbols have to be quoted from
the shell.

Updates in usage text:
 - Specified parameter format for "--cmd" option.
 - Added an instruction how to get help for "--cmd" option.

Signed-off-by: Maria Kustova <maria.k@catit.be>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
qcow2: Correct comment for realloc_refcount_block()

Contrary to the comment describing this function's behavior, it does not
return 0 on success, but rather the offset of the newly allocated
cluster. This patch adjusts the comment accordingly to reflect the
actual behavior.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
qcow2: Fix fail path in realloc_refcount_block()

If qcow2_alloc_clusters() fails, new_offset and ret will both be
negative after the fail label, thus passing the first if condition and
subsequently resulting in a call of qcow2_free_clusters() with an
invalid (negative) offset parameter. Fix this by introducing a new label
"fail_free_cluster" which is only invoked if new_offset is indeed
pointing to a newly allocated cluster that should be cleaned up by
freeing it.

While we're at it, clean up the whole fail path. qcow2_cache_put()
should (and actually can) never fail, hence the return value can safely
be ignored (aside from asserting that it indeed did not fail).

Furthermore, there is no reason to give QCOW2_DISCARD_ALWAYS to
qcow2_free_clusters(), a mere QCOW2_DISCARD_OTHER will suffice.

Ultimately, rename the "fail" label to "done", as it is invoked both on
failure and success.

Suggested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
block/nfs: bump libnfs requirement to 1.9.3

libnfs prior to 1.9.3 contains a bug that will report
wrong transfer sizes if the file offset grows beyond 4GB
and RPC responses are received out of order. this
error is not detectable and fixable in qemu.

additionally 1.9.3 introduces support for handling short
read/writes in general and takes care of the necessary
retransmissions internally.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
block/nfs: report errors from libnfs

if an NFS operation fails we should report what libnfs knows
about the failure. It is likely more than just an error code.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>