[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20120112202308.GA2030@phenom.dumpdata.com>
Date: Thu, 12 Jan 2012 15:23:09 -0500
From: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
To: "Cihula, Joseph" <joseph.cihula@...el.com>
Cc: "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"rjw@...k.pl" <rjw@...k.pl>, "x86@...nel.org" <x86@...nel.org>,
"Brown, Len" <len.brown@...el.com>,
"linux-pm@...ts.linux-foundation.org"
<linux-pm@...ts.linux-foundation.org>,
"tboot-devel@...ts.sourceforge.net"
<tboot-devel@...ts.sourceforge.net>,
"linux-acpi@...r.kernel.org" <linux-acpi@...r.kernel.org>,
"liang.tang@...cle.com" <liang.tang@...cle.com>,
"hpa@...or.com" <hpa@...or.com>
Subject: Re: [PATCH 2/7] tboot: Add return values for tboot_sleep
On Thu, Jan 12, 2012 at 09:49:58AM -0800, Konrad Rzeszutek Wilk wrote:
> On Tue, Jan 10, 2012 at 08:10:53PM +0000, Cihula, Joseph wrote:
> > ACK, but tboot_sleep() calls tboot_shutdown() and there are error conditions in that which you are not reflecting upward--i.e. you should make tboot_shutdown() return an 'int' and propagate its errors through tboot_sleep().
>
> Hey Joe,
>
> Thanks for looking at the patches.
>
> Right now [with this patch applied] the code looks as so:
>
> 297
> 298 tboot_shutdown(acpi_shutdown_map[sleep_state]);
> 299 return 0;
> 300 }
>
>
> If we do make tboot_shutdown() return an int, there will be a need to modify
> other callers: native_machine_emergency_restart, native_machine_halt,
> native_machine_power_off, and native_play_dead as well.
>
> Perhaps that could be done in another patch and leave this one as is
> where the 'tboot_sleep' would just return 0 instead of
> 'return tboot_shutdown(...)' ?
>
> Perhaps another way to do this is to extract the common code of tboot_sleep
> and tboot_shutdown?
Like this (not yet tested):
diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index 6410744..2f93a50 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -212,17 +212,16 @@ static int tboot_setup_sleep(void)
{
/* S3 shutdown requested, but S3 not supported by the kernel... */
BUG();
- return -1;
+ return -ENOSYS;
}
#endif
-void tboot_shutdown(u32 shutdown_type)
-{
- void (*shutdown)(void);
+static int tboot_check(u32 shutdown_type) {
+
if (!tboot_enabled())
- return;
+ return -ENODEV;
/*
* if we're being called before the 1:1 mapping is set up then just
@@ -230,12 +229,21 @@ void tboot_shutdown(u32 shutdown_type)
* due to very early panic()
*/
if (!tboot_pg_dir)
- return;
+ return -EBUSY;
/* if this is S3 then set regions to MAC */
- if (shutdown_type == TB_SHUTDOWN_S3)
- if (tboot_setup_sleep())
- return;
+ if (shutdown_type == TB_SHUTDOWN_S3) {
+ int err = tboot_setup_sleep();
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+static void __tboot_shutdown(u32 shutdown_type)
+{
+ void (*shutdown)(void);
tboot->shutdown_type = shutdown_type;
@@ -248,6 +256,13 @@ void tboot_shutdown(u32 shutdown_type)
while (1)
halt();
}
+void tboot_shutdown(u32 shutdown_type)
+{
+ if (!tboot_check(shutdown_type))
+ return;
+
+ __tboot_shutdown(shutdown_type);
+}
static void tboot_copy_fadt(const struct acpi_table_fadt *fadt)
{
@@ -279,9 +294,17 @@ static int tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
/* S3: */ TB_SHUTDOWN_S3,
/* S4: */ TB_SHUTDOWN_S4,
/* S5: */ TB_SHUTDOWN_S5 };
+ int err;
- if (!tboot_enabled())
- return 0;
+ if (sleep_state >= ACPI_S_STATE_COUNT ||
+ acpi_shutdown_map[sleep_state] == -1) {
+ pr_warning("unsupported sleep state 0x%x\n", sleep_state);
+ return -ENOSYS;
+ }
+
+ err = tboot_check(acpi_shutdown_map[sleep_state]);
+ if (!err && err != EBUSY)
+ return err;
tboot_copy_fadt(&acpi_gbl_FADT);
tboot->acpi_sinfo.pm1a_cnt_val = pm1a_control;
@@ -289,13 +312,7 @@ static int tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
/* we always use the 32b wakeup vector */
tboot->acpi_sinfo.vector_width = 32;
- if (sleep_state >= ACPI_S_STATE_COUNT ||
- acpi_shutdown_map[sleep_state] == -1) {
- pr_warning("unsupported sleep state 0x%x\n", sleep_state);
- return -1;
- }
-
- tboot_shutdown(acpi_shutdown_map[sleep_state]);
+ __tboot_shutdown((acpi_shutdown_map[sleep_state]));
return 0;
}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists