[PATCH v3 2/6] drivers:hv: Move MMIO range picking from hyper_fb.mod to hv_vmbus.mod
From: jakeo
Date: Wed Jun 17 2015 - 13:18:26 EST
From: Jake Oshins <jakeo@xxxxxxxxxxxxx>
Currently, hv_vmbus finds the ranges of memory-mapped I/O space that are
designated for paravirtual (and fully virtual) devices by the virtual
firmware (BIOS or UEFI) and exports the answer. The hyperv_fb video
driver then takes that information and uses it to claim a range of MMIO
space.
This patch moves the logic for deciding which sub-range of MMIO space to
claim from hyperv_fb to hv_vmbus, so that other drivers can share the
same logic. It is also slightly expanded so that it searches all of the
potential MMIO ranges described by the ACPI namespace.
Signed-off-by: Jake Oshins <jakeo@xxxxxxxxxxxxx>
---
drivers/hv/vmbus_drv.c | 83 ++++++++++++++++++++++++++++++++++++++++-
drivers/video/fbdev/hyperv_fb.c | 46 +++++++++++------------
include/linux/hyperv.h | 7 +++-
3 files changed, 108 insertions(+), 28 deletions(-)
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index d0e8832..9b4fc1a 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -39,6 +39,7 @@
#include <asm/mshyperv.h>
#include <linux/notifier.h>
#include <linux/ptrace.h>
+#include <linux/screen_info.h>
#include "hyperv_vmbus.h"
static struct acpi_device *hv_acpi_dev;
@@ -73,7 +74,6 @@ static struct notifier_block hyperv_panic_block = {
};
struct resource *hyperv_mmio;
-EXPORT_SYMBOL_GPL(hyperv_mmio);
static int vmbus_exists(void)
{
@@ -1073,6 +1073,87 @@ static int vmbus_acpi_remove(struct acpi_device *device)
return 0;
}
+/**
+ * vmbus_allocate_mmio() - Pick a memory-mapped I/O range.
+ * @new: If successful, supplied a pointer to the allocated MMIO
+ * space.
+ * @device_obj: Identifies the caller
+ * @min: Minimum guest physical address of the allocation
+ * @max: Maximum guest physical address
+ * @size: Size of the range to be allocated
+ * @align: Alignment of the range to be allocated
+ * @fb_overlap_ok: Whether this allocation can be allowed to
+ * overlap the video frame buffer.
+ *
+ * This function walks the resources granted to VMBus by the
+ * _CRS object in the ACPI namespace underneath the parent
+ * "bridge" whether that's a root PCI bus in the Generation 1
+ * case or a Module Device in the Generation 2 case. It then
+ * attempts to allocate from the global MMIO pool in a way that
+ * matches the constraints supplied in these parameters and by
+ * that _CRS.
+ *
+ * Return: 0 on success, -errno on failure
+ *
+ */
+int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
+ resource_size_t min, resource_size_t max,
+ resource_size_t size, resource_size_t align,
+ bool fb_overlap_ok)
+{
+ struct resource *iter;
+ resource_size_t range_min, range_max, start, local_min, local_max;
+ const char *dev_n = dev_name(&device_obj->device);
+ u32 fb_end = screen_info.lfb_base + (screen_info.lfb_size << 1);
+ int i;
+
+ for (iter = hyperv_mmio; iter; iter = iter->sibling) {
+
+ if ((iter->start >= max) || (iter->end <= min))
+ continue;
+
+ range_min = iter->start;
+ range_max = iter->end;
+
+ /* If this range overlaps the frame buffer, split it into
+ two tries. */
+ for (i = 0; i < 2; i++) {
+ local_min = range_min;
+ local_max = range_max;
+ if (fb_overlap_ok || ((range_min >= fb_end) ||
+ (range_max <= screen_info.lfb_base))) {
+ i++;
+ } else {
+ if ((range_min <= screen_info.lfb_base) &&
+ (range_max >= screen_info.lfb_base)) {
+
+ /*
+ * The frame buffer is in this window,
+ * so trim this into the part that
+ * preceeds the frame buffer.
+ */
+ local_max = screen_info.lfb_base-1;
+ range_min = fb_end;
+ } else {
+ range_min = fb_end;
+ continue;
+ }
+ }
+
+ start = (local_min + align - 1) & ~(align - 1);
+ for (; start + size - 1 <= local_max; start += align) {
+ *new = request_mem_region_exclusive(start, size,
+ dev_n);
+ if (*new)
+ return 0;
+ }
+ }
+ }
+
+ return -ENXIO;
+}
+EXPORT_SYMBOL_GPL(vmbus_allocate_mmio);
+
static int vmbus_acpi_add(struct acpi_device *device)
{
acpi_status result;
diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
index b54ee1c..e2451bd 100644
--- a/drivers/video/fbdev/hyperv_fb.c
+++ b/drivers/video/fbdev/hyperv_fb.c
@@ -213,7 +213,7 @@ struct synthvid_msg {
struct hvfb_par {
struct fb_info *info;
- struct resource mem;
+ struct resource *mem;
bool fb_ready; /* fb device is ready */
struct completion wait;
u32 synthvid_version;
@@ -677,26 +677,18 @@ static void hvfb_get_option(struct fb_info *info)
/* Get framebuffer memory from Hyper-V video pci space */
-static int hvfb_getmem(struct fb_info *info)
+static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
{
struct hvfb_par *par = info->par;
struct pci_dev *pdev = NULL;
void __iomem *fb_virt;
int gen2vm = efi_enabled(EFI_BOOT);
+ resource_size_t pot_start, pot_end;
int ret;
- par->mem.name = KBUILD_MODNAME;
- par->mem.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
if (gen2vm) {
- ret = allocate_resource(hyperv_mmio, &par->mem,
- screen_fb_size,
- 0, -1,
- screen_fb_size,
- NULL, NULL);
- if (ret != 0) {
- pr_err("Unable to allocate framebuffer memory\n");
- return -ENODEV;
- }
+ pot_start = 0;
+ pot_end = -1;
} else {
pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
@@ -709,16 +701,18 @@ static int hvfb_getmem(struct fb_info *info)
pci_resource_len(pdev, 0) < screen_fb_size)
goto err1;
- par->mem.end = pci_resource_end(pdev, 0);
- par->mem.start = par->mem.end - screen_fb_size + 1;
- ret = request_resource(&pdev->resource[0], &par->mem);
- if (ret != 0) {
- pr_err("Unable to request framebuffer memory\n");
- goto err1;
- }
+ pot_end = pci_resource_end(pdev, 0);
+ pot_start = pot_end - screen_fb_size + 1;
+ }
+
+ ret = vmbus_allocate_mmio(&par->mem, hdev, pot_start, pot_end,
+ screen_fb_size, 0x100000, true);
+ if (ret != 0) {
+ pr_err("Unable to allocate framebuffer memory\n");
+ goto err1;
}
- fb_virt = ioremap(par->mem.start, screen_fb_size);
+ fb_virt = ioremap(par->mem->start, screen_fb_size);
if (!fb_virt)
goto err2;
@@ -736,7 +730,7 @@ static int hvfb_getmem(struct fb_info *info)
info->apertures->ranges[0].size = pci_resource_len(pdev, 0);
}
- info->fix.smem_start = par->mem.start;
+ info->fix.smem_start = par->mem->start;
info->fix.smem_len = screen_fb_size;
info->screen_base = fb_virt;
info->screen_size = screen_fb_size;
@@ -749,7 +743,8 @@ static int hvfb_getmem(struct fb_info *info)
err3:
iounmap(fb_virt);
err2:
- release_resource(&par->mem);
+ release_mem_region(par->mem->start, screen_fb_size);
+ par->mem = NULL;
err1:
if (!gen2vm)
pci_dev_put(pdev);
@@ -763,7 +758,8 @@ static void hvfb_putmem(struct fb_info *info)
struct hvfb_par *par = info->par;
iounmap(info->screen_base);
- release_resource(&par->mem);
+ release_mem_region(par->mem->start, screen_fb_size);
+ par->mem = NULL;
}
@@ -794,7 +790,7 @@ static int hvfb_probe(struct hv_device *hdev,
goto error1;
}
- ret = hvfb_getmem(info);
+ ret = hvfb_getmem(hdev, info);
if (ret) {
pr_err("No memory for framebuffer\n");
goto error2;
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 21fa867..ffd98d7 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -982,6 +982,11 @@ int __must_check __vmbus_driver_register(struct hv_driver *hv_driver,
const char *mod_name);
void vmbus_driver_unregister(struct hv_driver *hv_driver);
+int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
+ resource_size_t min, resource_size_t max,
+ resource_size_t size, resource_size_t align,
+ bool fb_overlap_ok);
+
/**
* VMBUS_DEVICE - macro used to describe a specific hyperv vmbus device
*
@@ -1245,8 +1250,6 @@ void hv_vss_deinit(void);
void hv_vss_onchannelcallback(void *);
void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid);
-extern struct resource *hyperv_mmio;
-
/*
* Negotiated version with the Host.
*/
--
1.9.1
--
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