[v3,4/6] xen/arm: handle reserved-memory in consider_modules and dt_unreserved_regions

Commit Message

Stefano Stabellini June 21, 2019, 11:56 p.m. UTC

reserved-memory regions overlap with memory nodes. The overlapping
memory is reserved-memory and should be handled accordingly:
consider_modules and dt_unreserved_regions should skip these regions the
same way they are already skipping mem-reserve regions.

Signed-off-by: Stefano Stabellini <[e-mail]>
---
Changes in v3:
- coding style
- in-code comments

Changes in v2:
- fix commit message: full overlap
- remove check_reserved_memory
- extend consider_modules and dt_unreserved_regions
---
 xen/arch/arm/setup.c | 53 +++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 50 insertions(+), 3 deletions(-)

Comments

Julien Grall July 10, 2019, 4:40 p.m. UTC | #1

Hi Stefano,

On 6/22/19 12:56 AM, Stefano Stabellini wrote:
> diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
> index 215746a5c3..d9cfb1aa2f 100644
> --- a/xen/arch/arm/setup.c
> +++ b/xen/arch/arm/setup.c
> @@ -206,6 +206,28 @@ void __init dt_unreserved_regions(paddr_t s, paddr_t e,
>           }
>       }
>   
> +    /*
> +     * i is the current bootmodule we are evaluating across all possible
> +     * kinds.
> +     *
> +     * When retrieving the corresponding reserved-memory addresses
> +     * below, we need to index the bootinfo.reserved_mem bank starting
> +     * from 0, and only counting the reserved-memory modules. Hence,
> +     * we need to use i - nr.
> +     */
> +    for ( ; i - nr < bootinfo.reserved_mem.nr_banks; i++ )
> +    {
> +        paddr_t r_s = bootinfo.reserved_mem.bank[i - nr].start;
> +        paddr_t r_e = r_s + bootinfo.reserved_mem.bank[i - nr].size;
> +
> +        if ( s < r_e && r_s < e )
> +        {
> +            dt_unreserved_regions(r_e, e, cb, i+1);

Coding style: space before and after the operator. Ideally, the rest of

> +            dt_unreserved_regions(s, r_s, cb, i+1);

Ditto.

With that:

Acked-by: Julien Grall <[e-mail]>

Cheers,

Patch

diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 215746a5c3..d9cfb1aa2f 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -206,6 +206,28 @@  void __init dt_unreserved_regions(paddr_t s, paddr_t e,
         }
     }
 
+    /*
+     * i is the current bootmodule we are evaluating across all possible
+     * kinds.
+     *
+     * When retrieving the corresponding reserved-memory addresses
+     * below, we need to index the bootinfo.reserved_mem bank starting
+     * from 0, and only counting the reserved-memory modules. Hence,
+     * we need to use i - nr.
+     */
+    for ( ; i - nr < bootinfo.reserved_mem.nr_banks; i++ )
+    {
+        paddr_t r_s = bootinfo.reserved_mem.bank[i - nr].start;
+        paddr_t r_e = r_s + bootinfo.reserved_mem.bank[i - nr].size;
+
+        if ( s < r_e && r_s < e )
+        {
+            dt_unreserved_regions(r_e, e, cb, i+1);
+            dt_unreserved_regions(s, r_s, cb, i+1);
+            return;
+        }
+    }
+
     cb(s, e);
 }
 
@@ -392,7 +414,7 @@  static paddr_t __init consider_modules(paddr_t s, paddr_t e,
 {
     const struct bootmodules *mi = &bootinfo.modules;
     int i;
-    int nr_rsvd;
+    int nr;
 
     s = (s+align-1) & ~(align-1);
     e = e & ~(align-1);
@@ -418,9 +440,9 @@  static paddr_t __init consider_modules(paddr_t s, paddr_t e,
 
     /* Now check any fdt reserved areas. */
 
-    nr_rsvd = fdt_num_mem_rsv(device_tree_flattened);
+    nr = fdt_num_mem_rsv(device_tree_flattened);
 
-    for ( ; i < mi->nr_mods + nr_rsvd; i++ )
+    for ( ; i < mi->nr_mods + nr; i++ )
     {
         paddr_t mod_s, mod_e;
 
@@ -442,6 +464,31 @@  static paddr_t __init consider_modules(paddr_t s, paddr_t e,
             return consider_modules(s, mod_s, size, align, i+1);
         }
     }
+
+    /*
+     * i is the current bootmodule we are evaluating, across all
+     * possible kinds of bootmodules.
+     *
+     * When retrieving the corresponding reserved-memory addresses, we
+     * need to index the bootinfo.reserved_mem bank starting from 0, and
+     * only counting the reserved-memory modules. Hence, we need to use
+     * i - nr.
+     */
+    nr += mi->nr_mods;
+    for ( ; i - nr < bootinfo.reserved_mem.nr_banks; i++ )
+    {
+        paddr_t r_s = bootinfo.reserved_mem.bank[i - nr].start;
+        paddr_t r_e = r_s + bootinfo.reserved_mem.bank[i - nr].size;
+
+        if ( s < r_e && r_s < e )
+        {
+            r_e = consider_modules(r_e, e, size, align, i + 1);
+            if ( r_e )
+                return r_e;
+
+            return consider_modules(s, r_s, size, align, i + 1);
+        }
+    }
     return e;
 }
 #endif