From: Oleksandr Tyshchenko <olekstysh@gmail.com>
To: xen-devel@lists.xenproject.org
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>,
Stefano Stabellini <sstabellini@kernel.org>,
Julien Grall <julien@xen.org>,
Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>,
Julien Grall <julien.grall@arm.com>
Subject: [PATCH V2 19/23] xen/arm: io: Abstract sign-extension
Date: Thu, 15 Oct 2020 19:44:30 +0300 [thread overview]
Message-ID: <1602780274-29141-20-git-send-email-olekstysh@gmail.com> (raw)
In-Reply-To: <1602780274-29141-1-git-send-email-olekstysh@gmail.com>
From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
In order to avoid code duplication (both handle_read() and
handle_ioserv() contain the same code for the sign-extension)
put this code to a common helper to be used for both.
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
CC: Julien Grall <julien.grall@arm.com>
---
Please note, this is a split/cleanup/hardening of Julien's PoC:
"Add support for Guest IO forwarding to a device emulator"
Changes V1 -> V2:
- new patch
---
xen/arch/arm/io.c | 18 ++----------------
xen/arch/arm/ioreq.c | 17 +----------------
xen/include/asm-arm/traps.h | 24 ++++++++++++++++++++++++
3 files changed, 27 insertions(+), 32 deletions(-)
diff --git a/xen/arch/arm/io.c b/xen/arch/arm/io.c
index f44cfd4..8d6ec6c 100644
--- a/xen/arch/arm/io.c
+++ b/xen/arch/arm/io.c
@@ -23,6 +23,7 @@
#include <asm/cpuerrata.h>
#include <asm/current.h>
#include <asm/mmio.h>
+#include <asm/traps.h>
#include <asm/hvm/ioreq.h>
#include "decode.h"
@@ -39,26 +40,11 @@ static enum io_state handle_read(const struct mmio_handler *handler,
* setting r).
*/
register_t r = 0;
- uint8_t size = (1 << dabt.size) * 8;
if ( !handler->ops->read(v, info, &r, handler->priv) )
return IO_ABORT;
- /*
- * Sign extend if required.
- * Note that we expect the read handler to have zeroed the bits
- * outside the requested access size.
- */
- if ( dabt.sign && (r & (1UL << (size - 1))) )
- {
- /*
- * We are relying on register_t using the same as
- * an unsigned long in order to keep the 32-bit assembly
- * code smaller.
- */
- BUILD_BUG_ON(sizeof(register_t) != sizeof(unsigned long));
- r |= (~0UL) << size;
- }
+ r = sign_extend(dabt, r);
set_user_reg(regs, dabt.reg, r);
diff --git a/xen/arch/arm/ioreq.c b/xen/arch/arm/ioreq.c
index da5ceac..ad17b80 100644
--- a/xen/arch/arm/ioreq.c
+++ b/xen/arch/arm/ioreq.c
@@ -28,7 +28,6 @@ enum io_state handle_ioserv(struct cpu_user_regs *regs, struct vcpu *v)
const union hsr hsr = { .bits = regs->hsr };
const struct hsr_dabt dabt = hsr.dabt;
/* Code is similar to handle_read */
- uint8_t size = (1 << dabt.size) * 8;
register_t r = v->io.io_req.data;
/* We are done with the IO */
@@ -37,21 +36,7 @@ enum io_state handle_ioserv(struct cpu_user_regs *regs, struct vcpu *v)
if ( dabt.write )
return IO_HANDLED;
- /*
- * Sign extend if required.
- * Note that we expect the read handler to have zeroed the bits
- * outside the requested access size.
- */
- if ( dabt.sign && (r & (1UL << (size - 1))) )
- {
- /*
- * We are relying on register_t using the same as
- * an unsigned long in order to keep the 32-bit assembly
- * code smaller.
- */
- BUILD_BUG_ON(sizeof(register_t) != sizeof(unsigned long));
- r |= (~0UL) << size;
- }
+ r = sign_extend(dabt, r);
set_user_reg(regs, dabt.reg, r);
diff --git a/xen/include/asm-arm/traps.h b/xen/include/asm-arm/traps.h
index 997c378..e301c44 100644
--- a/xen/include/asm-arm/traps.h
+++ b/xen/include/asm-arm/traps.h
@@ -83,6 +83,30 @@ static inline bool VABORT_GEN_BY_GUEST(const struct cpu_user_regs *regs)
(unsigned long)abort_guest_exit_end == regs->pc;
}
+/* Check whether the sign extension is required and perform it */
+static inline register_t sign_extend(const struct hsr_dabt dabt, register_t r)
+{
+ uint8_t size = (1 << dabt.size) * 8;
+
+ /*
+ * Sign extend if required.
+ * Note that we expect the read handler to have zeroed the bits
+ * outside the requested access size.
+ */
+ if ( dabt.sign && (r & (1UL << (size - 1))) )
+ {
+ /*
+ * We are relying on register_t using the same as
+ * an unsigned long in order to keep the 32-bit assembly
+ * code smaller.
+ */
+ BUILD_BUG_ON(sizeof(register_t) != sizeof(unsigned long));
+ r |= (~0UL) << size;
+ }
+
+ return r;
+}
+
#endif /* __ASM_ARM_TRAPS__ */
/*
* Local variables:
--
2.7.4
next prev parent reply other threads:[~2020-10-15 16:53 UTC|newest]
Thread overview: 109+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-15 16:44 [PATCH V2 00/23] IOREQ feature (+ virtio-mmio) on Arm Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 01/23] x86/ioreq: Prepare IOREQ feature for making it common Oleksandr Tyshchenko
2020-10-20 7:13 ` Paul Durrant
2020-11-04 9:06 ` Oleksandr
2020-11-04 9:59 ` Paul Durrant
2020-11-12 10:58 ` Jan Beulich
2020-11-13 11:09 ` Oleksandr
2020-11-13 11:20 ` Jan Beulich
2020-11-13 12:45 ` Oleksandr
2020-11-13 14:31 ` Jan Beulich
2020-10-15 16:44 ` [PATCH V2 02/23] xen/ioreq: Make x86's IOREQ feature common Oleksandr Tyshchenko
2020-10-20 7:57 ` Paul Durrant
2020-11-10 16:45 ` Oleksandr
2020-11-17 14:47 ` Oleksandr
2020-11-17 15:29 ` Paul Durrant
2020-11-17 16:29 ` Oleksandr
2020-11-17 19:43 ` Paul Durrant
2020-11-12 11:11 ` Jan Beulich
2020-11-13 13:11 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 03/23] xen/ioreq: Make x86's hvm_ioreq_needs_completion() common Oleksandr Tyshchenko
2020-10-20 7:59 ` Paul Durrant
2020-10-15 16:44 ` [PATCH V2 04/23] xen/ioreq: Provide alias for the handle_mmio() Oleksandr Tyshchenko
2020-10-20 9:14 ` Paul Durrant
2020-10-20 10:05 ` Jan Beulich
2020-10-20 10:38 ` Paul Durrant
2020-11-10 19:44 ` Oleksandr
2020-11-11 7:27 ` Jan Beulich
2020-11-11 8:09 ` Oleksandr
2020-11-11 8:16 ` Jan Beulich
2020-10-15 16:44 ` [PATCH V2 05/23] xen/ioreq: Make x86's hvm_mmio_first(last)_byte() common Oleksandr Tyshchenko
2020-10-20 9:15 ` Paul Durrant
2020-10-15 16:44 ` [PATCH V2 06/23] xen/ioreq: Make x86's hvm_ioreq_(page/vcpu/server) structs common Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 07/23] xen/ioreq: Move x86's ioreq_gfn(server) to struct domain Oleksandr Tyshchenko
2020-11-12 11:21 ` Jan Beulich
2020-11-13 14:05 ` Oleksandr
2020-11-18 12:09 ` Oleksandr
2020-11-18 12:29 ` Paul Durrant
2020-10-15 16:44 ` [PATCH V2 08/23] xen/ioreq: Introduce ioreq_params to abstract accesses to arch.hvm.params Oleksandr Tyshchenko
2020-10-20 10:41 ` Paul Durrant
2020-11-10 20:00 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 09/23] xen/dm: Make x86's DM feature common Oleksandr Tyshchenko
2020-11-12 11:32 ` Jan Beulich
2020-11-13 14:28 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 10/23] xen/mm: Make x86's XENMEM_resource_ioreq_server handling common Oleksandr Tyshchenko
2020-11-12 11:40 ` Jan Beulich
2020-11-13 15:00 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 11/23] xen/ioreq: Move x86's io_completion/io_req fields to struct vcpu Oleksandr Tyshchenko
2020-10-20 10:55 ` Paul Durrant
2020-11-10 20:59 ` Oleksandr
2020-11-11 8:04 ` Jan Beulich
2020-11-11 8:14 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 12/23] xen/ioreq: Remove "hvm" prefixes from involved function names Oleksandr Tyshchenko
2020-11-12 11:45 ` Jan Beulich
2020-11-12 12:14 ` Paul Durrant
2020-11-13 15:53 ` Oleksandr
2020-11-23 14:39 ` Oleksandr
2020-11-23 14:56 ` Jan Beulich
2020-11-23 15:47 ` Oleksandr
2020-11-23 15:54 ` Paul Durrant
2020-11-23 16:36 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 13/23] xen/ioreq: Use guest_cmpxchg64() instead of cmpxchg() Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 14/23] arm/ioreq: Introduce arch specific bits for IOREQ/DM features Oleksandr Tyshchenko
2020-11-12 11:48 ` Jan Beulich
2020-11-13 15:48 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 15/23] xen/arm: Stick around in leave_hypervisor_to_guest until I/O has completed Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 16/23] xen/mm: Handle properly reference in set_foreign_p2m_entry() on Arm Oleksandr Tyshchenko
2020-11-12 12:18 ` Jan Beulich
2020-11-13 17:00 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 17/23] xen/ioreq: Introduce domain_has_ioreq_server() Oleksandr Tyshchenko
2020-10-20 10:51 ` Paul Durrant
2020-11-10 20:53 ` Oleksandr
2020-11-11 8:08 ` Jan Beulich
2020-11-11 8:41 ` Oleksandr
2020-11-11 13:27 ` Jan Beulich
2020-11-11 16:28 ` Paul Durrant
2020-11-11 17:33 ` Oleksandr
2020-11-11 17:31 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 18/23] xen/dm: Introduce xendevicemodel_set_irq_level DM op Oleksandr Tyshchenko
2020-10-15 16:44 ` Oleksandr Tyshchenko [this message]
2020-10-15 16:44 ` [PATCH V2 20/23] xen/ioreq: Make x86's send_invalidate_req() common Oleksandr Tyshchenko
2020-11-12 11:55 ` Jan Beulich
2020-11-13 16:03 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 21/23] xen/arm: Add mapcache invalidation handling Oleksandr Tyshchenko
2020-10-16 6:29 ` Jan Beulich
2020-10-16 8:41 ` Julien Grall
2020-10-16 8:56 ` Jan Beulich
2020-11-11 0:03 ` Oleksandr
2020-11-11 19:27 ` Julien Grall
2020-11-11 19:42 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 22/23] libxl: Introduce basic virtio-mmio support on Arm Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 23/23] [RFC] libxl: Add support for virtio-disk configuration Oleksandr Tyshchenko
2020-11-09 6:45 ` Wei Chen
2020-11-11 0:53 ` Oleksandr
2020-11-11 4:28 ` Wei Chen
2020-11-13 17:38 ` Oleksandr
2020-10-29 7:41 ` [PATCH V2 00/23] IOREQ feature (+ virtio-mmio) on Arm Masami Hiramatsu
2020-10-29 18:48 ` Oleksandr Tyshchenko
2020-10-29 19:53 ` Stefano Stabellini
2020-10-29 21:13 ` Oleksandr Tyshchenko
2020-10-29 21:34 ` Stefano Stabellini
2020-10-30 11:34 ` Masami Hiramatsu
2020-10-31 21:10 ` Oleksandr Tyshchenko
2020-11-02 7:23 ` Wei Chen
2020-11-02 18:05 ` Oleksandr
2020-11-03 14:30 ` Masami Hiramatsu
2020-11-03 21:09 ` Oleksandr
2020-10-29 20:03 ` Alex Bennée
2020-10-29 20:10 ` Stefano Stabellini
2020-10-29 22:06 ` Oleksandr Tyshchenko
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