@@ -90,6 +90,7 @@
#define DIRECTMAP_SLOT_START 200
#define DIRECTMAP_VIRT_START SLOTN(DIRECTMAP_SLOT_START)
#define DIRECTMAP_SIZE (SLOTN(DIRECTMAP_SLOT_END) - SLOTN(DIRECTMAP_SLOT_START))
+#define XENHEAP_VIRT_START directmap_virt_start
#define FRAMETABLE_SCALE_FACTOR (PAGE_SIZE/sizeof(struct page_info))
#define FRAMETABLE_SIZE_IN_SLOTS (((DIRECTMAP_SIZE / SLOTN(1)) / FRAMETABLE_SCALE_FACTOR) + 1)
@@ -12,6 +12,8 @@
#include <asm/page-bits.h>
+extern vaddr_t directmap_virt_start;
+
#define pfn_to_paddr(pfn) ((paddr_t)(pfn) << PAGE_SHIFT)
#define paddr_to_pfn(pa) ((unsigned long)((pa) >> PAGE_SHIFT))
@@ -25,8 +27,11 @@
static inline void *maddr_to_virt(paddr_t ma)
{
- BUG_ON("unimplemented");
- return NULL;
+ unsigned long va_offset = maddr_to_directmapoff(ma);
+
+ ASSERT(va_offset < DIRECTMAP_SIZE);
+
+ return (void *)(XENHEAP_VIRT_START + va_offset);
}
/*
@@ -37,9 +42,9 @@ static inline void *maddr_to_virt(paddr_t ma)
*/
static inline unsigned long virt_to_maddr(unsigned long va)
{
- if ((va >= DIRECTMAP_VIRT_START) &&
+ if ((va >= XENHEAP_VIRT_START) &&
(va < (DIRECTMAP_VIRT_START + DIRECTMAP_SIZE)))
- return directmapoff_to_maddr(va - DIRECTMAP_VIRT_START);
+ return directmapoff_to_maddr(va - XENHEAP_VIRT_START);
BUILD_BUG_ON(XEN_VIRT_SIZE != MB(2));
ASSERT((va >> (PAGETABLE_ORDER + PAGE_SHIFT)) ==
@@ -5,6 +5,8 @@
#define max_init_domid (0)
+void setup_mm(void);
+
#endif /* ASM__RISCV__SETUP_H */
/*
@@ -8,6 +8,7 @@
#include <xen/libfdt/libfdt.h>
#include <xen/macros.h>
#include <xen/mm.h>
+#include <xen/pdx.h>
#include <xen/pfn.h>
#include <xen/sections.h>
#include <xen/sizes.h>
@@ -423,3 +424,123 @@ void * __init early_fdt_map(paddr_t fdt_paddr)
return fdt_virt;
}
+
+#ifndef CONFIG_RISCV_32
+
+#define ROUNDDOWN(addr, size) ((addr) & ~((size) - 1))
+
+/* Map a frame table to cover physical addresses ps through pe */
+static void __init setup_frametable_mappings(paddr_t ps, paddr_t pe)
+{
+ paddr_t aligned_ps = ROUNDDOWN(ps, PAGE_SIZE);
+ paddr_t aligned_pe = ROUNDUP(pe, PAGE_SIZE);
+ unsigned long nr_mfns = PFN_DOWN(aligned_pe - aligned_ps);
+ unsigned long frametable_size = nr_mfns * sizeof(struct page_info);
+ mfn_t base_mfn;
+
+ if ( frametable_size > FRAMETABLE_SIZE )
+ panic("The frametable cannot cover the physical region [%#"PRIpaddr" - %#"PRIpaddr")\n",
+ ps, pe);
+
+ frametable_size = ROUNDUP(frametable_size, MB(2));
+ base_mfn = alloc_boot_pages(frametable_size >> PAGE_SHIFT, PFN_DOWN(MB(2)));
+
+ if ( map_pages_to_xen(FRAMETABLE_VIRT_START, base_mfn,
+ PFN_DOWN(frametable_size),
+ PAGE_HYPERVISOR_RW) )
+ panic("Unable to setup the frametable mappings\n");
+
+ memset(&frame_table[0], 0, nr_mfns * sizeof(struct page_info));
+ memset(&frame_table[nr_mfns], -1,
+ frametable_size - (nr_mfns * sizeof(struct page_info)));
+}
+
+
+static mfn_t __ro_after_init directmap_mfn_start = INVALID_MFN_INITIALIZER;
+vaddr_t __ro_after_init directmap_virt_start;
+
+/* Map the region in the directmap area. */
+static void __init setup_directmap_mappings(unsigned long base_mfn,
+ unsigned long nr_mfns)
+{
+ int rc;
+
+ /* First call sets the directmap physical and virtual offset. */
+ if ( mfn_eq(directmap_mfn_start, INVALID_MFN) )
+ {
+ directmap_mfn_start = _mfn(base_mfn);
+
+ /*
+ * The base address may not be aligned to the second level
+ * size (e.g. 1GB when using 4KB pages). This would prevent
+ * superpage mappings for all the regions because the virtual
+ * address and machine address should both be suitably aligned.
+ *
+ * Prevent that by offsetting the start of the directmap virtual
+ * address.
+ */
+ directmap_virt_start = DIRECTMAP_VIRT_START + pfn_to_paddr(base_mfn);
+ }
+
+ if ( base_mfn < mfn_x(directmap_mfn_start) )
+ panic("cannot add directmap mapping at %#lx below heap start %#lx\n",
+ base_mfn, mfn_x(directmap_mfn_start));
+
+ rc = map_pages_to_xen((vaddr_t)mfn_to_virt(base_mfn),
+ _mfn(base_mfn), nr_mfns,
+ PAGE_HYPERVISOR_RW);
+ if ( rc )
+ panic("Unable to setup the directmap mappings.\n");
+}
+
+/*
+ * Setup memory management
+ *
+ * RISC-V 64 has a large virtual address space (the minimum supported
+ * MMU mode is Sv39, which provides TBs of VA space).
+ * In the case of RISC-V 64, the directmap and frametable are mapped
+ * starting from physical address 0 to simplify the page_to_mfn(),
+ * mfn_to_page(), and maddr_to_virt() calculations, as there is no need
+ * to account for {directmap, frametable}_base_pdx in this setup.
+ */
+void __init setup_mm(void)
+{
+ const struct membanks *banks = bootinfo_get_mem();
+ paddr_t ram_start = INVALID_PADDR;
+ paddr_t ram_end = 0;
+ paddr_t ram_size = 0;
+ unsigned int i;
+
+ /*
+ * We need some memory to allocate the page-tables used for the directmap
+ * mappings. But some regions may contain memory already allocated
+ * for other uses (e.g. modules, reserved-memory...).
+ *
+ * For simplicity, add all the free regions in the boot allocator.
+ */
+ populate_boot_allocator();
+
+ total_pages = 0;
+
+ for ( i = 0; i < banks->nr_banks; i++ )
+ {
+ const struct membank *bank = &banks->bank[i];
+ paddr_t bank_end = bank->start + bank->size;
+
+ ram_size += ROUNDDOWN(bank->size, PAGE_SIZE);
+ ram_start = min(ram_start, bank->start);
+ ram_end = max(ram_end, bank_end);
+
+ setup_directmap_mappings(PFN_DOWN(bank->start),
+ PFN_DOWN(bank->size));
+ }
+
+ total_pages = PFN_DOWN(ram_size);
+
+ setup_frametable_mappings(0, ram_end);
+ max_page = PFN_DOWN(ram_end);
+}
+
+#else /* CONFIG_RISCV_32 */
+#error setup_mm(), setup_{directmap,frametable}_mapping() should be implemented for RV_32
+#endif
@@ -12,6 +12,7 @@
#include <asm/early_printk.h>
#include <asm/sbi.h>
+#include <asm/setup.h>
#include <asm/smp.h>
#include <asm/traps.h>
@@ -59,6 +60,8 @@ void __init noreturn start_xen(unsigned long bootcpu_id,
printk("Command line: %s\n", cmdline);
cmdline_parse(cmdline);
+ setup_mm();
+
printk("All set up\n");
machine_halt();
@@ -2,7 +2,9 @@
#include <xen/cpumask.h>
#include <xen/domain.h>
#include <xen/irq.h>
+#include <xen/mm.h>
#include <xen/nodemask.h>
+#include <xen/sched.h>
#include <xen/sections.h>
#include <xen/time.h>
#include <public/domctl.h>
@@ -409,3 +411,11 @@ unsigned long get_upper_mfn_bound(void)
{
BUG_ON("unimplemented");
}
+
+/* mm.c */
+
+void share_xen_page_with_guest(struct page_info *page, struct domain *d,
+ enum XENSHARE_flags flags)
+{
+ BUG_ON("unimplemented");
+}
Introduce the implementation of setup_mm(), which includes: 1. Adding all free regions to the boot allocator, as memory is needed to allocate page tables used for frame table mapping. 2. Calculating RAM size and the RAM end address. 3. Setting up direct map mappings from each RAM bank and initialize directmap_virt_start (also introduce XENHEAP_VIRT_START which is defined as directmap_virt_start) to be properly aligned with RAM start to use more superpages to reduce pressure on the TLB. 4. Setting up frame table mappings from physical address 0 to ram_end to simplify mfn_to_page() and page_to_mfn() conversions. 5. Setting up total_pages and max_page. Update virt_to_maddr() to use introduced XENHEAP_VIRT_START. Implement maddr_to_virt() function to convert a machine address to a virtual address. This function is specifically designed to be used only for the DIRECTMAP region, so a check has been added to ensure that the address does not exceed DIRECTMAP_SIZE. After the introduction of maddr_to_virt() the following linkage error starts to occur and to avoid it share_xen_page_with_guest() stub is added: riscv64-linux-gnu-ld: prelink.o: in function `tasklet_kill': /build/xen/common/tasklet.c:176: undefined reference to `share_xen_page_with_guest' riscv64-linux-gnu-ld: ./.xen-syms.0: hidden symbol `share_xen_page_with_guest' isn't defined riscv64-linux-gnu-ld: final link failed: bad value Despite the linkger fingering tasklet.c, it's trace.o which has the undefined refenrece: $ find . -name \*.o | while read F; do nm $F | grep share_xen_page_with_guest && echo $F; done U share_xen_page_with_guest ./xen/common/built_in.o U share_xen_page_with_guest ./xen/common/trace.o U share_xen_page_with_guest ./xen/prelink.o Looking at trace.i, there is call of share_xen_page_with_guest() but in case of when maddr_to_virt() is defined as "return NULL" compiler optimizes the part of common/trace.c code where share_xen_page_with_priviliged_guest() is called ( there is no any code in dissambled common/trace.o ) so there is no real call of share_xen_page_with_priviliged_guest(). Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com> --- Changes in V2: - merge patch 2 ( xen/riscv: implement maddr_to_virt() ) to the current one as maddr_to_virt() started to use the thing which are introduced in the current patch. - merge with patch 1 ( xen/riscv: add stub for share_xen_page_with_guest() ) as this linkage issue happens during introduction of maddr_to_virt(). - use mathematical range expressions for log messages. - calculate properly amount of mfns in setup_frametable_mapping() taking into account that ps and pe can be not properly aligned. - drop full stop at the end of debug message. - use PFN_DOWN(framsetable_size) instead of frametable_size >> PAGE_SHIFT. - round down ram_size when it is being accumulated in setup_mm() to guarantee that banks can never have partial pages at their start/end. - call setup_directmap_mappings() only for ram bank regions instead of mapping [0, ram_end] region. - drop directmap_virt_end for now as it isn't used at the moment. - update the commit message. --- xen/arch/riscv/include/asm/config.h | 1 + xen/arch/riscv/include/asm/mm.h | 13 ++- xen/arch/riscv/include/asm/setup.h | 2 + xen/arch/riscv/mm.c | 121 ++++++++++++++++++++++++++++ xen/arch/riscv/setup.c | 3 + xen/arch/riscv/stubs.c | 10 +++ 6 files changed, 146 insertions(+), 4 deletions(-)