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authorLinus Torvalds <torvalds@linux-foundation.org>2015-09-02 01:20:51 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-09-02 01:20:51 +0300
commit43af9872f52abfed5523b8346d98a5e283b38163 (patch)
treef50f52c5dfc47ed06972d10a20f01feeff7300d9 /arch/x86/lguest
parent17e6b00ac422b49d44a0b8d98402a211f726282d (diff)
parenta47d4576cd1c58157a2d8cfffa93aa7ca375eede (diff)
downloadlinux-43af9872f52abfed5523b8346d98a5e283b38163.tar.xz
Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 apic updates from Thomas Gleixner: "This udpate contains: - rework the irq vector array to store a pointer to the irq descriptor instead of the irq number to avoid a lookup of the irq descriptor in the irq entry path - lguest interrupt handling cleanups - conversion of the local apic timer to the new clockevent callbacks - preparatory changes for the irq argument removal of interrupt flow handlers" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/irq: Do not dereference irq descriptor before checking it tools/lguest: Clean up include dir tools/lguest: Fix redefinition of struct virtio_pci_cfg_cap x86/irq: Store irq descriptor in vector array genirq: Provide irq_desc_has_action x86/irq: Get rid of an indentation level x86/irq: Rename VECTOR_UNDEFINED to VECTOR_UNUSED x86/irq: Replace numeric constant x86/irq: Protect smp_cleanup_move x86/lguest: Do not setup unused irq vectors x86/lguest: Clean up lguest_setup_irq x86/apic: Drop local_irq_save/restore in timer callbacks x86/apic: Migrate apic timer to new set_state interface x86/irq: Use access helper irq_data_get_affinity_mask() x86/irq: Use accessor irq_data_get_irq_handler_data() x86/irq: Use accessor irq_data_get_node()
Diffstat (limited to 'arch/x86/lguest')
-rw-r--r--arch/x86/lguest/boot.c67
1 files changed, 37 insertions, 30 deletions
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 433e5a7dd37f..161804de124a 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
@@ -1028,7 +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);