From: Denis Mukhin <dmukhin@ford.com>
guest_console_write() duplicates the code from __putstr(), eliminate code
duplication.
Introduce console_puts() for writing a buffer to console devices.
Also, introduce internal console flags to control which console devices
should be used.
No functional change intended.
Signed-off-by: Denis Mukhin <dmukhin@ford.com>
---
Changes since v2:
- added CONSOLE_RING_VIRQ flag
- dropped locking changes
---
xen/drivers/char/console.c | 123 ++++++++++++++++++++++++-------------
1 file changed, 79 insertions(+), 44 deletions(-)
diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c
index 20504060cb..b788427aa5 100644
--- a/xen/drivers/char/console.c
+++ b/xen/drivers/char/console.c
@@ -41,6 +41,28 @@
#include <asm/vpl011.h>
#endif
+/* Internal console flags. */
+enum {
+ CONSOLE_SERIAL = BIT(0, U), /* Use serial device. */
+ CONSOLE_PV = BIT(1, U), /* Use PV console. */
+ CONSOLE_VIDEO = BIT(2, U), /* Use video device. */
+ CONSOLE_DEBUG = BIT(3, U), /* Use debug device. */
+ CONSOLE_RING = BIT(4, U), /* Use console ring. */
+ CONSOLE_RING_VIRQ = BIT(5, U), /* Use console ring VIRQ. */
+
+ /* Default console flags. */
+ CONSOLE_DEFAULT = CONSOLE_SERIAL |
+ CONSOLE_PV |
+ CONSOLE_VIDEO |
+ CONSOLE_RING_VIRQ |
+ CONSOLE_DEBUG,
+
+ /* Use all known console devices. */
+ CONSOLE_ALL = CONSOLE_DEFAULT | CONSOLE_RING,
+};
+
+static void console_puts(const char *str, size_t len, unsigned int flags);
+
/* console: comma-separated list of console outputs. */
static char __initdata opt_console[30] = OPT_CONSOLE_STR;
string_param("console", opt_console);
@@ -431,9 +453,6 @@ void console_serial_puts(const char *s, size_t nr)
serial_steal_fn(s, nr);
else
serial_puts(sercon_handle, s, nr);
-
- /* Copy all serial output into PV console */
- pv_console_puts(s, nr);
}
static void cf_check dump_console_ring_key(unsigned char key)
@@ -467,8 +486,7 @@ static void cf_check dump_console_ring_key(unsigned char key)
c += len;
}
- console_serial_puts(buf, sofar);
- video_puts(buf, sofar);
+ console_puts(buf, sofar, CONSOLE_SERIAL | CONSOLE_VIDEO | CONSOLE_PV);
free_xenheap_pages(buf, order);
}
@@ -617,11 +635,66 @@ static inline void xen_console_write_debug_port(const char *buf, size_t len)
}
#endif
+static inline void console_debug_puts(const char *str, size_t len)
+{
+#ifdef CONFIG_X86
+ if ( opt_console_xen )
+ {
+ if ( xen_guest )
+ xen_hypercall_console_write(str, len);
+ else
+ xen_console_write_debug_port(str, len);
+ }
+#endif
+}
+
+/*
+ * Write buffer to all enabled console devices.
+ *
+ * That will handle all possible scenarios working w/ console
+ * - physical console (serial console, VGA console (x86 only));
+ * - PV console;
+ * - debug console (x86 only): debug I/O port or __HYPERVISOR_console_io
+ * hypercall;
+ * - console ring.
+ */
+static void console_puts(const char *str, size_t len, unsigned int flags)
+{
+ if ( flags & CONSOLE_SERIAL )
+ console_serial_puts(str, len);
+
+ if ( flags & CONSOLE_PV )
+ pv_console_puts(str, len);
+
+ if ( flags & CONSOLE_VIDEO )
+ video_puts(str, len);
+
+ if ( flags & CONSOLE_DEBUG )
+ console_debug_puts(str, len);
+
+ if ( flags & CONSOLE_RING )
+ conring_puts(str, len, !!(flags & CONSOLE_RING_VIRQ) );
+}
+
+static inline void __putstr(const char *str)
+{
+ unsigned int flags = CONSOLE_ALL;
+
+ ASSERT(rspin_is_locked(&console_lock));
+
+ if ( conring_no_notify )
+ flags &= ~CONSOLE_RING_VIRQ;
+
+ console_puts(str, strlen(str), flags);
+}
+
static long guest_console_write(XEN_GUEST_HANDLE_PARAM(char) buffer,
unsigned int count)
{
char kbuf[128];
unsigned int kcount = 0;
+ unsigned int flags = opt_console_to_ring
+ ? CONSOLE_ALL : CONSOLE_DEFAULT;
struct domain *cd = current->domain;
while ( count > 0 )
@@ -639,23 +712,7 @@ static long guest_console_write(XEN_GUEST_HANDLE_PARAM(char) buffer,
{
/* Use direct console output as it could be interactive */
nrspin_lock_irq(&console_lock);
-
- console_serial_puts(kbuf, kcount);
- video_puts(kbuf, kcount);
-
-#ifdef CONFIG_X86
- if ( opt_console_xen )
- {
- if ( xen_guest )
- xen_hypercall_console_write(kbuf, kcount);
- else
- xen_console_write_debug_port(kbuf, kcount);
- }
-#endif
-
- if ( opt_console_to_ring )
- conring_puts(kbuf, kcount, true);
-
+ console_puts(kbuf, kcount, flags);
nrspin_unlock_irq(&console_lock);
}
else
@@ -756,28 +813,6 @@ long do_console_io(
* *****************************************************
*/
-static void __putstr(const char *str)
-{
- size_t len = strlen(str);
-
- ASSERT(rspin_is_locked(&console_lock));
-
- console_serial_puts(str, len);
- video_puts(str, len);
-
-#ifdef CONFIG_X86
- if ( opt_console_xen )
- {
- if ( xen_guest )
- xen_hypercall_console_write(str, len);
- else
- xen_console_write_debug_port(str, len);
- }
-#endif
-
- conring_puts(str, len, !conring_no_notify);
-}
-
static int printk_prefix_check(char *p, char **pp)
{
int loglvl = -1;
--
2.34.1On Sun, 4 May 2025, dmkhn@proton.me wrote:
> From: Denis Mukhin <dmukhin@ford.com>
>
> guest_console_write() duplicates the code from __putstr(), eliminate code
> duplication.
>
> Introduce console_puts() for writing a buffer to console devices.
>
> Also, introduce internal console flags to control which console devices
> should be used.
>
> No functional change intended.
>
> Signed-off-by: Denis Mukhin <dmukhin@ford.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
> ---
> Changes since v2:
> - added CONSOLE_RING_VIRQ flag
> - dropped locking changes
> ---
> xen/drivers/char/console.c | 123 ++++++++++++++++++++++++-------------
> 1 file changed, 79 insertions(+), 44 deletions(-)
>
> diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c
> index 20504060cb..b788427aa5 100644
> --- a/xen/drivers/char/console.c
> +++ b/xen/drivers/char/console.c
> @@ -41,6 +41,28 @@
> #include <asm/vpl011.h>
> #endif
>
> +/* Internal console flags. */
> +enum {
> + CONSOLE_SERIAL = BIT(0, U), /* Use serial device. */
> + CONSOLE_PV = BIT(1, U), /* Use PV console. */
> + CONSOLE_VIDEO = BIT(2, U), /* Use video device. */
> + CONSOLE_DEBUG = BIT(3, U), /* Use debug device. */
> + CONSOLE_RING = BIT(4, U), /* Use console ring. */
> + CONSOLE_RING_VIRQ = BIT(5, U), /* Use console ring VIRQ. */
> +
> + /* Default console flags. */
> + CONSOLE_DEFAULT = CONSOLE_SERIAL |
> + CONSOLE_PV |
> + CONSOLE_VIDEO |
> + CONSOLE_RING_VIRQ |
> + CONSOLE_DEBUG,
> +
> + /* Use all known console devices. */
> + CONSOLE_ALL = CONSOLE_DEFAULT | CONSOLE_RING,
> +};
> +
> +static void console_puts(const char *str, size_t len, unsigned int flags);
> +
> /* console: comma-separated list of console outputs. */
> static char __initdata opt_console[30] = OPT_CONSOLE_STR;
> string_param("console", opt_console);
> @@ -431,9 +453,6 @@ void console_serial_puts(const char *s, size_t nr)
> serial_steal_fn(s, nr);
> else
> serial_puts(sercon_handle, s, nr);
> -
> - /* Copy all serial output into PV console */
> - pv_console_puts(s, nr);
> }
>
> static void cf_check dump_console_ring_key(unsigned char key)
> @@ -467,8 +486,7 @@ static void cf_check dump_console_ring_key(unsigned char key)
> c += len;
> }
>
> - console_serial_puts(buf, sofar);
> - video_puts(buf, sofar);
> + console_puts(buf, sofar, CONSOLE_SERIAL | CONSOLE_VIDEO | CONSOLE_PV);
>
> free_xenheap_pages(buf, order);
> }
> @@ -617,11 +635,66 @@ static inline void xen_console_write_debug_port(const char *buf, size_t len)
> }
> #endif
>
> +static inline void console_debug_puts(const char *str, size_t len)
> +{
> +#ifdef CONFIG_X86
> + if ( opt_console_xen )
> + {
> + if ( xen_guest )
> + xen_hypercall_console_write(str, len);
> + else
> + xen_console_write_debug_port(str, len);
> + }
> +#endif
> +}
> +
> +/*
> + * Write buffer to all enabled console devices.
> + *
> + * That will handle all possible scenarios working w/ console
> + * - physical console (serial console, VGA console (x86 only));
> + * - PV console;
> + * - debug console (x86 only): debug I/O port or __HYPERVISOR_console_io
> + * hypercall;
> + * - console ring.
> + */
> +static void console_puts(const char *str, size_t len, unsigned int flags)
> +{
> + if ( flags & CONSOLE_SERIAL )
> + console_serial_puts(str, len);
> +
> + if ( flags & CONSOLE_PV )
> + pv_console_puts(str, len);
> +
> + if ( flags & CONSOLE_VIDEO )
> + video_puts(str, len);
> +
> + if ( flags & CONSOLE_DEBUG )
> + console_debug_puts(str, len);
> +
> + if ( flags & CONSOLE_RING )
> + conring_puts(str, len, !!(flags & CONSOLE_RING_VIRQ) );
> +}
> +
> +static inline void __putstr(const char *str)
> +{
> + unsigned int flags = CONSOLE_ALL;
> +
> + ASSERT(rspin_is_locked(&console_lock));
> +
> + if ( conring_no_notify )
> + flags &= ~CONSOLE_RING_VIRQ;
> +
> + console_puts(str, strlen(str), flags);
> +}
> +
> static long guest_console_write(XEN_GUEST_HANDLE_PARAM(char) buffer,
> unsigned int count)
> {
> char kbuf[128];
> unsigned int kcount = 0;
> + unsigned int flags = opt_console_to_ring
> + ? CONSOLE_ALL : CONSOLE_DEFAULT;
> struct domain *cd = current->domain;
>
> while ( count > 0 )
> @@ -639,23 +712,7 @@ static long guest_console_write(XEN_GUEST_HANDLE_PARAM(char) buffer,
> {
> /* Use direct console output as it could be interactive */
> nrspin_lock_irq(&console_lock);
> -
> - console_serial_puts(kbuf, kcount);
> - video_puts(kbuf, kcount);
> -
> -#ifdef CONFIG_X86
> - if ( opt_console_xen )
> - {
> - if ( xen_guest )
> - xen_hypercall_console_write(kbuf, kcount);
> - else
> - xen_console_write_debug_port(kbuf, kcount);
> - }
> -#endif
> -
> - if ( opt_console_to_ring )
> - conring_puts(kbuf, kcount, true);
> -
> + console_puts(kbuf, kcount, flags);
> nrspin_unlock_irq(&console_lock);
> }
> else
> @@ -756,28 +813,6 @@ long do_console_io(
> * *****************************************************
> */
>
> -static void __putstr(const char *str)
> -{
> - size_t len = strlen(str);
> -
> - ASSERT(rspin_is_locked(&console_lock));
> -
> - console_serial_puts(str, len);
> - video_puts(str, len);
> -
> -#ifdef CONFIG_X86
> - if ( opt_console_xen )
> - {
> - if ( xen_guest )
> - xen_hypercall_console_write(str, len);
> - else
> - xen_console_write_debug_port(str, len);
> - }
> -#endif
> -
> - conring_puts(str, len, !conring_no_notify);
> -}
> -
> static int printk_prefix_check(char *p, char **pp)
> {
> int loglvl = -1;
> --
> 2.34.1
>
>
On Fri, 16 May 2025, Stefano Stabellini wrote: > On Sun, 4 May 2025, dmkhn@proton.me wrote: > > From: Denis Mukhin <dmukhin@ford.com> > > > > guest_console_write() duplicates the code from __putstr(), eliminate code > > duplication. > > > > Introduce console_puts() for writing a buffer to console devices. > > > > Also, introduce internal console flags to control which console devices > > should be used. > > > > No functional change intended. > > > > Signed-off-by: Denis Mukhin <dmukhin@ford.com> > > Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Sorry I replied to the wrong version, I meant to ack v4.
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