Remove PNP resources from "available space" used by allocate_resource(). This would be better done by putting the PNP resources directly in the resource maps (iomem_resource, etc), but there are some issues that keep us from doing that yet. This patch keeps us from handing out PNP device address space to other callers of allocate_resource(). Reference: https://bugzilla.kernel.org/show_bug.cgi?id=23332 Reference: https://bugzilla.kernel.org/show_bug.cgi?id=23542 Reference: https://bugzilla.kernel.org/show_bug.cgi?id=23802 Reported-by: Matthew Garrett <mjg@xxxxxxxxxx> Reported-by: Dan Williams <dcbw@xxxxxxxxxx> Reported-by: Jiri Slaby <jirislaby@xxxxxxxxx> Signed-off-by: Bjorn Helgaas <bjorn.helgaas@xxxxxx> --- arch/x86/kernel/resource.c | 78 ++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 78 insertions(+), 0 deletions(-) diff --git a/arch/x86/kernel/resource.c b/arch/x86/kernel/resource.c index 5dd6473..1daee92 100644 --- a/arch/x86/kernel/resource.c +++ b/arch/x86/kernel/resource.c @@ -1,6 +1,80 @@ #include <linux/ioport.h> +#include <linux/pnp.h> #include <asm/e820.h> +#ifdef CONFIG_PNP +static bool resource_conflict(struct resource *res, resource_size_t start, + resource_size_t end) +{ + /* + * Return true if and only if "res" conflicts with the [start-end] + * range. + */ + return res->start <= end && res->end >= start; +} + +static void resource_split(struct resource *res, resource_size_t start, + resource_size_t end, struct resource *low, + struct resource *high) +{ + /* + * If "res" conflicts with [start-end], split "res" into the + * part below "start" (low) and the part above "end" (high), + * either (or both) of which may be empty. + * + * If there's no conflict, return the entire "res" as "low". + */ + *low = *res; + low->start = res->start; + low->end = res->start - 1; /* default to empty (size 0) */ + + *high = *res; + high->end = res->end; + high->start = res->end + 1; /* default to empty (size 0) */ + + if (!resource_conflict(res, start, end)) { + low->end = res->end; + return; + } + + if (res->start < start) + low->end = start - 1; + + if (res->end > end) + high->start = end + 1; +} + +static void pnp_remove_reservations(struct resource *avail) +{ + unsigned long type = resource_type(avail); + struct pnp_dev *dev; + int i; + struct resource *res, low, high; + + /* + * Clip the available region to avoid PNP devices. The PNP + * resources really should be in the resource map to begin with, + * but there are still some issues preventing that. + */ + pnp_for_each_dev(dev) { + i = 0; + res = pnp_get_resource(dev, type, i++); + while (res) { + if (!(res->flags & IORESOURCE_WINDOW)) { + resource_split(avail, res->start, res->end, + &low, &high); + if (resource_size(&low) > resource_size(&high)) + *avail = low; + else + *avail = high; + } + + res = pnp_get_resource(dev, type, i++); + } + } +} +#endif + void arch_remove_reservations(struct resource *avail) { /* @@ -11,4 +85,8 @@ void arch_remove_reservations(struct resource *avail) if (avail->start < BIOS_END) avail->start = BIOS_END; } + +#ifdef CONFIG_PNP + pnp_remove_reservations(avail); +#endif } -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
