diff options
Diffstat (limited to 'arch/x86/lguest')
-rw-r--r-- | arch/x86/lguest/boot.c | 91 |
1 files changed, 43 insertions, 48 deletions
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c index f2dc08c00..a0d09f6c6 100644 --- a/arch/x86/lguest/boot.c +++ b/arch/x86/lguest/boot.c @@ -835,16 +835,46 @@ static struct irq_chip lguest_irq_controller = { .irq_unmask = enable_lguest_irq, }; +/* + * Interrupt descriptors are allocated as-needed, but low-numbered ones are + * reserved by the generic x86 code. So we ignore irq_alloc_desc_at if it + * tells us the irq is already used: other errors (ie. ENOMEM) we take + * seriously. + */ +static int lguest_setup_irq(unsigned int irq) +{ + struct irq_desc *desc; + int err; + + /* Returns -ve error or vector number. */ + err = irq_alloc_desc_at(irq, 0); + if (err < 0 && err != -EEXIST) + return err; + + /* + * Tell the Linux infrastructure that the interrupt is + * controlled by our level-based lguest interrupt controller. + */ + irq_set_chip_and_handler_name(irq, &lguest_irq_controller, + handle_level_irq, "level"); + + /* Some systems map "vectors" to interrupts weirdly. Not us! */ + desc = irq_to_desc(irq); + __this_cpu_write(vector_irq[FIRST_EXTERNAL_VECTOR + irq], desc); + return 0; +} + static int lguest_enable_irq(struct pci_dev *dev) { + int err; u8 line = 0; /* We literally use the PCI interrupt line as the irq number. */ pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &line); - irq_set_chip_and_handler_name(line, &lguest_irq_controller, - handle_level_irq, "level"); - dev->irq = line; - return 0; + err = lguest_setup_irq(line); + if (!err) + dev->irq = line; + return err; } /* We don't do hotplug PCI, so this shouldn't be called. */ @@ -855,17 +885,13 @@ static void lguest_disable_irq(struct pci_dev *dev) /* * This sets up the Interrupt Descriptor Table (IDT) entry for each hardware - * interrupt (except 128, which is used for system calls), and then tells the - * Linux infrastructure that each interrupt is controlled by our level-based - * lguest interrupt controller. + * interrupt (except 128, which is used for system calls). */ static void __init lguest_init_IRQ(void) { unsigned int i; for (i = FIRST_EXTERNAL_VECTOR; i < FIRST_SYSTEM_VECTOR; i++) { - /* Some systems map "vectors" to interrupts weirdly. Not us! */ - __this_cpu_write(vector_irq[i], i - FIRST_EXTERNAL_VECTOR); if (i != IA32_SYSCALL_VECTOR) set_intr_gate(i, irq_entries_start + 8 * (i - FIRST_EXTERNAL_VECTOR)); @@ -879,26 +905,6 @@ static void __init lguest_init_IRQ(void) } /* - * Interrupt descriptors are allocated as-needed, but low-numbered ones are - * reserved by the generic x86 code. So we ignore irq_alloc_desc_at if it - * tells us the irq is already used: other errors (ie. ENOMEM) we take - * seriously. - */ -int lguest_setup_irq(unsigned int irq) -{ - int err; - - /* Returns -ve error or vector number. */ - err = irq_alloc_desc_at(irq, 0); - if (err < 0 && err != -EEXIST) - return err; - - irq_set_chip_and_handler_name(irq, &lguest_irq_controller, - handle_level_irq, "level"); - return 0; -} - -/* * Time. * * It would be far better for everyone if the Guest had its own clock, but @@ -985,23 +991,11 @@ static int lguest_clockevent_set_next_event(unsigned long delta, return 0; } -static void lguest_clockevent_set_mode(enum clock_event_mode mode, - struct clock_event_device *evt) +static int lguest_clockevent_shutdown(struct clock_event_device *evt) { - switch (mode) { - case CLOCK_EVT_MODE_UNUSED: - case CLOCK_EVT_MODE_SHUTDOWN: - /* A 0 argument shuts the clock down. */ - hcall(LHCALL_SET_CLOCKEVENT, 0, 0, 0, 0); - break; - case CLOCK_EVT_MODE_ONESHOT: - /* This is what we expect. */ - break; - case CLOCK_EVT_MODE_PERIODIC: - BUG(); - case CLOCK_EVT_MODE_RESUME: - break; - } + /* A 0 argument shuts the clock down. */ + hcall(LHCALL_SET_CLOCKEVENT, 0, 0, 0, 0); + return 0; } /* This describes our primitive timer chip. */ @@ -1009,7 +1003,7 @@ static struct clock_event_device lguest_clockevent = { .name = "lguest", .features = CLOCK_EVT_FEAT_ONESHOT, .set_next_event = lguest_clockevent_set_next_event, - .set_mode = lguest_clockevent_set_mode, + .set_state_shutdown = lguest_clockevent_shutdown, .rating = INT_MAX, .mult = 1, .shift = 0, @@ -1021,7 +1015,7 @@ static struct clock_event_device lguest_clockevent = { * This is the Guest timer interrupt handler (hardware interrupt 0). We just * call the clockevent infrastructure and it does whatever needs doing. */ -static void lguest_time_irq(unsigned int irq, struct irq_desc *desc) +static void lguest_time_irq(struct irq_desc *desc) { unsigned long flags; @@ -1040,7 +1034,8 @@ static void lguest_time_irq(unsigned int irq, struct irq_desc *desc) static void lguest_time_init(void) { /* Set up the timer interrupt (0) to go to our simple timer routine */ - lguest_setup_irq(0); + if (lguest_setup_irq(0) != 0) + panic("Could not set up timer irq"); irq_set_handler(0, lguest_time_irq); clocksource_register_hz(&lguest_clock, NSEC_PER_SEC); |