[xen master] arm/mpu: Implement setup_frametable_mappings for MPU systems

[patchbot@xxxxxxx]

commit 6addccb789e17b22ff67d0f8d4862d3e5d1e6758
Author:     Luca Fancellu <luca.fancellu@xxxxxxx>
AuthorDate: Thu Aug 28 12:12:03 2025 +0100
Commit:     Michal Orzel <michal.orzel@xxxxxxx>
CommitDate: Thu Sep 4 10:18:50 2025 +0200

    arm/mpu: Implement setup_frametable_mappings for MPU systems
    
    Implement the MPU variant of `setup_frametable_mappings`. This function
    will be called by `setup_mm` when an implementation for MPU systems is
    added in a follow up commit.
    
    Signed-off-by: Luca Fancellu <luca.fancellu@xxxxxxx>
    Signed-off-by: Hari Limaye <hari.limaye@xxxxxxx>
    Reviewed-by: Michal Orzel <michal.orzel@xxxxxxx>
---
 xen/arch/arm/mpu/mm.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/xen/arch/arm/mpu/mm.c b/xen/arch/arm/mpu/mm.c
index c6891607ec..3f155b7db2 100644
--- a/xen/arch/arm/mpu/mm.c
+++ b/xen/arch/arm/mpu/mm.c
@@ -168,6 +168,39 @@ int mpumap_contains_region(pr_t *table, uint8_t 
nr_regions, paddr_t base,
     return MPUMAP_REGION_NOTFOUND;
 }
 
+/* Map a frame table to cover physical addresses ps through pe */
+void __init setup_frametable_mappings(paddr_t ps, paddr_t pe)
+{
+    mfn_t base_mfn;
+    paddr_t aligned_ps = ROUNDUP(ps, PAGE_SIZE);
+    paddr_t aligned_pe = ROUNDDOWN(pe, PAGE_SIZE);
+
+    unsigned long nr_pdxs = mfn_to_pdx(mfn_add(maddr_to_mfn(aligned_pe), -1)) -
+                            mfn_to_pdx(maddr_to_mfn(aligned_ps)) + 1;
+    unsigned long frametable_size = nr_pdxs * sizeof(struct page_info);
+
+    /*
+     * The size of paddr_t should be sufficient for the complete range of
+     * physical address.
+     */
+    BUILD_BUG_ON((sizeof(paddr_t) * BITS_PER_BYTE) < PADDR_BITS);
+    BUILD_BUG_ON(sizeof(struct page_info) != PAGE_INFO_SIZE);
+
+    if ( frametable_size > FRAMETABLE_SIZE )
+        panic("The frametable cannot cover the physical region %#"PRIpaddr" - 
%#"PRIpaddr"\n",
+              ps, pe);
+
+    frametable_base_pdx = paddr_to_pdx(aligned_ps);
+    frametable_size = ROUNDUP(frametable_size, PAGE_SIZE);
+
+    base_mfn = alloc_boot_pages(frametable_size >> PAGE_SHIFT, 1);
+    frame_table = (struct page_info *)mfn_to_virt(mfn_x(base_mfn));
+
+    memset(&frame_table[0], 0, nr_pdxs * sizeof(struct page_info));
+    memset(&frame_table[nr_pdxs], -1,
+           frametable_size - (nr_pdxs * sizeof(struct page_info)));
+}
+
 /*
  * Allocate an entry for a new EL2 MPU region in the bitmap xen_mpumap_mask.
  * @param idx   Set to the index of the allocated EL2 MPU region on success.
--
generated by git-patchbot for /home/xen/git/xen.git#master