Hi Luca,
On 09/04/2024 13:45, Luca Fancellu wrote:
>
>
> The function find_unallocated_memory is using the same code to
> loop through 3 structure of the same type, in order to avoid
> code duplication, rework the code to have only one loop that
> goes through all the structures.
>
> Signed-off-by: Luca Fancellu <luca.fance...@arm.com>
> ---
> v2:
> - Add comment in the loop inside find_unallocated_memory to
> improve readability
> v1:
> - new patch
> ---
> ---
> xen/arch/arm/domain_build.c | 70 +++++++++++++------------------------
> 1 file changed, 25 insertions(+), 45 deletions(-)
>
> diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
> index 57cf92668ae6..269aaff4d067 100644
> --- a/xen/arch/arm/domain_build.c
> +++ b/xen/arch/arm/domain_build.c
> @@ -869,12 +869,14 @@ static int __init add_ext_regions(unsigned long s_gfn,
> unsigned long e_gfn,
> static int __init find_unallocated_memory(const struct kernel_info *kinfo,
> struct membanks *ext_regions)
> {
> - const struct membanks *kinfo_mem = kernel_info_get_mem_const(kinfo);
> - const struct membanks *mem = bootinfo_get_mem();
> - const struct membanks *reserved_mem = bootinfo_get_reserved_mem();
> + const struct membanks *mem_banks[] = {
> + bootinfo_get_mem(),
> + kernel_info_get_mem_const(kinfo),
> + bootinfo_get_reserved_mem(),
> + };
> struct rangeset *unalloc_mem;
> paddr_t start, end;
> - unsigned int i;
> + unsigned int i, j;
> int res;
>
> dt_dprintk("Find unallocated memory for extended regions\n");
> @@ -883,50 +885,28 @@ static int __init find_unallocated_memory(const struct
> kernel_info *kinfo,
> if ( !unalloc_mem )
> return -ENOMEM;
>
> - /* Start with all available RAM */
> - for ( i = 0; i < mem->nr_banks; i++ )
> - {
> - start = mem->bank[i].start;
> - end = mem->bank[i].start + mem->bank[i].size;
> - res = rangeset_add_range(unalloc_mem, PFN_DOWN(start),
> - PFN_DOWN(end - 1));
> - if ( res )
> + /*
> + * Exclude the following regions, in order:
> + * 1) Start with all available RAM
> + * 2) Remove RAM assigned to Dom0
> + * 3) Remove reserved memory
Given this commit and the previous code, I expect one call to
rangeset_add_range() and
3 calls to rangeset_remove_range(). However ...
> + * The order comes from the initialization of the variable "mem_banks"
> + * above
> + */
> + for ( i = 0; i < ARRAY_SIZE(mem_banks); i++ )
> + for ( j = 0; j < mem_banks[i]->nr_banks; j++ )
> {
> - printk(XENLOG_ERR "Failed to add: %#"PRIpaddr"->%#"PRIpaddr"\n",
> - start, end);
> - goto out;
> - }
> - }
> -
> - /* Remove RAM assigned to Dom0 */
> - for ( i = 0; i < kinfo_mem->nr_banks; i++ )
> - {
> - start = kinfo_mem->bank[i].start;
> - end = kinfo_mem->bank[i].start + kinfo_mem->bank[i].size;
> - res = rangeset_remove_range(unalloc_mem, PFN_DOWN(start),
> + start = mem_banks[i]->bank[j].start;
> + end = mem_banks[i]->bank[j].start + mem_banks[i]->bank[j].size;
> + res = rangeset_add_range(unalloc_mem, PFN_DOWN(start),
... here you always call rangeset_add_range() which is wrong. For direct mapped
domain
you would e.g. register its RAM region as extended region.
~Michal
