lib: sbi: Add sbi_domain_check_addr_range() function

We add sbi_domain_check_addr_range() helper function to check
whether a given address range is accessible under a particular
domain.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

diff --git a/include/sbi/sbi_domain.h b/include/sbi/sbi_domain.h
index bbb3effa2449a43f817debbc0112d35a33ea02f2..ab1a944b474b14d2377441934078a392281bbc2e 100644 (file)
--- a/include/sbi/sbi_domain.h
+++ b/include/sbi/sbi_domain.h
@@ -196,6 +196,21 @@ bool sbi_domain_check_addr(const struct sbi_domain *dom,
                           unsigned long addr, unsigned long mode,
                           unsigned long access_flags);
 
+/**
+ * Check whether we can access specified address range for given mode and
+ * memory region flags under a domain
+ * @param dom pointer to domain
+ * @param addr the start of the address range to be checked
+ * @param size the size of the address range to be checked
+ * @param mode the privilege mode of access
+ * @param access_flags bitmask of domain access types (enum sbi_domain_access)
+ * @return TRUE if access allowed otherwise FALSE
+ */
+bool sbi_domain_check_addr_range(const struct sbi_domain *dom,
+                                unsigned long addr, unsigned long size,
+                                unsigned long mode,
+                                unsigned long access_flags);
+
 /** Dump domain details on the console */
 void sbi_domain_dump(const struct sbi_domain *dom, const char *suffix);
 

diff --git a/lib/sbi/sbi_domain.c b/lib/sbi/sbi_domain.c
index 3813f1b2e97dd81d66279bced6aeb4fccb894bd6..dc825b0d95f636f4516e5adaf21b05b61734caaf 100644 (file)
--- a/lib/sbi/sbi_domain.c
+++ b/lib/sbi/sbi_domain.c
@@ -212,6 +212,44 @@ static bool is_region_before(const struct sbi_domain_memregion *regA,
        return false;
 }
 
+static const struct sbi_domain_memregion *find_region(
+                                               const struct sbi_domain *dom,
+                                               unsigned long addr)
+{
+       unsigned long rstart, rend;
+       struct sbi_domain_memregion *reg;
+
+       sbi_domain_for_each_memregion(dom, reg) {
+               rstart = reg->base;
+               rend = (reg->order < __riscv_xlen) ?
+                       rstart + ((1UL << reg->order) - 1) : -1UL;
+               if (rstart <= addr && addr <= rend)
+                       return reg;
+       }
+
+       return NULL;
+}
+
+static const struct sbi_domain_memregion *find_next_subset_region(
+                               const struct sbi_domain *dom,
+                               const struct sbi_domain_memregion *reg,
+                               unsigned long addr)
+{
+       struct sbi_domain_memregion *sreg, *ret = NULL;
+
+       sbi_domain_for_each_memregion(dom, sreg) {
+               if (sreg == reg || (sreg->base <= addr) ||
+                   !is_region_subset(sreg, reg))
+                       continue;
+
+               if (!ret || (sreg->base < ret->base) ||
+                   ((sreg->base == ret->base) && (sreg->order < ret->order)))
+                       ret = sreg;
+       }
+
+       return ret;
+}
+
 static int sanitize_domain(const struct sbi_platform *plat,
                           struct sbi_domain *dom)
 {
@@ -320,6 +358,37 @@ static int sanitize_domain(const struct sbi_platform *plat,
        return 0;
 }
 
+bool sbi_domain_check_addr_range(const struct sbi_domain *dom,
+                                unsigned long addr, unsigned long size,
+                                unsigned long mode,
+                                unsigned long access_flags)
+{
+       unsigned long max = addr + size;
+       const struct sbi_domain_memregion *reg, *sreg;
+
+       if (!dom)
+               return false;
+
+       while (addr < max) {
+               reg = find_region(dom, addr);
+               if (!reg)
+                       return false;
+
+               if (!sbi_domain_check_addr(dom, addr, mode, access_flags))
+                       return false;
+
+               sreg = find_next_subset_region(dom, reg, addr);
+               if (sreg)
+                       addr = sreg->base;
+               else if (reg->order < __riscv_xlen)
+                       addr = reg->base + (1UL << reg->order);
+               else
+                       break;
+       }
+
+       return true;
+}
+
 void sbi_domain_dump(const struct sbi_domain *dom, const char *suffix)
 {
        u32 i, k;