From 92178fcabbcd39fc9ccd4e58ec4be83dd5323a46 Mon Sep 17 00:00:00 2001 From: Finn Thain Date: Thu, 26 Oct 2017 22:45:24 -0400 Subject: m68k/mac: Add mutual exclusion for IOP interrupt polling The IOP interrupt handler iop_ism_irq() is used by the adb-iop driver to poll for ADB request completion. Unfortunately, it is not re-entrant. Fix the race condition by adding an iop_ism_irq_poll() function with suitable mutual exclusion. Tested-by: Stan Johnson Signed-off-by: Finn Thain Cc: Benjamin Herrenschmidt Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Geert Uytterhoeven --- arch/m68k/include/asm/mac_iop.h | 1 + arch/m68k/mac/iop.c | 9 +++++++++ drivers/macintosh/adb-iop.c | 4 +--- 3 files changed, 11 insertions(+), 3 deletions(-) diff --git a/arch/m68k/include/asm/mac_iop.h b/arch/m68k/include/asm/mac_iop.h index 42566fd052bc..d2a08e004e2c 100644 --- a/arch/m68k/include/asm/mac_iop.h +++ b/arch/m68k/include/asm/mac_iop.h @@ -158,6 +158,7 @@ extern void iop_complete_message(struct iop_msg *); extern void iop_upload_code(uint, __u8 *, uint, __u16); extern void iop_download_code(uint, __u8 *, uint, __u16); extern __u8 *iop_compare_code(uint, __u8 *, uint, __u16); +extern void iop_ism_irq_poll(uint); extern void iop_register_interrupts(void); diff --git a/arch/m68k/mac/iop.c b/arch/m68k/mac/iop.c index a2ea52db7d18..9bfa17015768 100644 --- a/arch/m68k/mac/iop.c +++ b/arch/m68k/mac/iop.c @@ -598,3 +598,12 @@ irqreturn_t iop_ism_irq(int irq, void *dev_id) } return IRQ_HANDLED; } + +void iop_ism_irq_poll(uint iop_num) +{ + unsigned long flags; + + local_irq_save(flags); + iop_ism_irq(0, (void *)iop_num); + local_irq_restore(flags); +} diff --git a/drivers/macintosh/adb-iop.c b/drivers/macintosh/adb-iop.c index f5f4da3d0b67..4b0ad3995497 100644 --- a/drivers/macintosh/adb-iop.c +++ b/drivers/macintosh/adb-iop.c @@ -29,8 +29,6 @@ /*#define DEBUG_ADB_IOP*/ -extern void iop_ism_irq(int, void *); - static struct adb_request *current_req; static struct adb_request *last_req; #if 0 @@ -265,7 +263,7 @@ int adb_iop_autopoll(int devs) void adb_iop_poll(void) { if (adb_iop_state == idle) adb_iop_start(); - iop_ism_irq(0, (void *) ADB_IOP); + iop_ism_irq_poll(ADB_IOP); } int adb_iop_reset_bus(void) -- cgit v1.2.3