[PATCH v2 14/15] x86, boot: copy rom to kernel space

From: Yinghai Lu
Date: Wed Mar 04 2015 - 03:02:58 EST


As EFI stub code could put them high when on 32bit or with exactmap=
on 64bit conf.

Check is the range is mapped, otherwise allocate new one and have
the rom data copied. So we could really avoid ioremap.

Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
---
arch/x86/pci/common.c | 47 +++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 45 insertions(+), 2 deletions(-)

diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 93577fb..a5de331 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -694,6 +694,48 @@ struct firmware_setup_pci_entry {

static LIST_HEAD(setup_pci_entries);

+static phys_addr_t check_copy(phys_addr_t start, unsigned long size)
+{
+ unsigned long start_pfn = PFN_DOWN(start);
+ unsigned long end_pfn = PFN_UP(start + size);
+ unsigned char *p, *q;
+ phys_addr_t pa_p, pa_q;
+ long sz = size;
+
+ if (pfn_range_is_mapped(start_pfn, end_pfn))
+ return start;
+
+ /* allocate and copy */
+ pa_p = memblock_alloc(size, PAGE_SIZE);
+ if (!pa_p)
+ return start;
+
+ p = phys_to_virt(pa_p);
+
+ pa_q = start;
+ while (sz > 0) {
+ long chunk_size = 64<<10;
+
+ if (chunk_size > sz)
+ chunk_size = sz;
+
+ q = early_memremap(pa_q, chunk_size);
+ if (!q) {
+ memblock_free(pa_p, size);
+ return start;
+ }
+ memcpy(p, q, chunk_size);
+ early_memunmap(q, chunk_size);
+ p += chunk_size;
+ pa_q += chunk_size;
+ sz -= chunk_size;
+ }
+
+ early_memunmap(start, size);
+
+ return pa_p;
+}
+
int __init fill_setup_pci_entries(void)
{
struct setup_data *data;
@@ -723,8 +765,9 @@ int __init fill_setup_pci_entries(void)
entry->vendor = rom->vendor;
entry->devid = rom->devid;
entry->pcilen = rom->pcilen;
- entry->romdata = pa_data +
- offsetof(struct pci_setup_rom, romdata);
+ entry->romdata = check_copy(pa_data +
+ offsetof(struct pci_setup_rom, romdata),
+ rom->pcilen);

list_add(&entry->list, &setup_pci_entries);

--
1.8.4.5

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