Skip to content

Commit

Permalink
powerpc/fadump: Reserve page-aligned boot_memory_size during fadump_r…
Browse files Browse the repository at this point in the history
…eserve_mem

This patch refactors all CMA related initialization and alignment code
to within fadump_cma_init() which gets called in the end. This also means
that we keep [reserve_dump_area_start, boot_memory_size] page aligned
during fadump_reserve_mem(). Then later in fadump_cma_init() we extract the
aligned chunk and provide it to CMA. This inherently also fixes an issue in
the current code where the reserve_dump_area_start is not aligned
when the physical memory can have holes and the suitable chunk starts at
an unaligned boundary.

After this we should be able to call fadump_cma_init() independently
later in setup_arch() where pageblock_order is non-zero.

Suggested-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/805d6b900968fb9402ad8f4e4775597db42085c4.1729146153.git.ritesh.list@gmail.com
  • Loading branch information
riteshharjani authored and mpe committed Oct 21, 2024
1 parent adfaec3 commit 6faeac5
Showing 1 changed file with 22 additions and 12 deletions.
34 changes: 22 additions & 12 deletions arch/powerpc/kernel/fadump.c
Original file line number Diff line number Diff line change
Expand Up @@ -80,7 +80,7 @@ static struct cma *fadump_cma;
*/
static void __init fadump_cma_init(void)
{
unsigned long long base, size;
unsigned long long base, size, end;
int rc;

if (!fw_dump.fadump_supported || !fw_dump.fadump_enabled ||
Expand All @@ -92,8 +92,24 @@ static void __init fadump_cma_init(void)
if (fw_dump.nocma || !fw_dump.boot_memory_size)
return;

/*
* [base, end) should be reserved during early init in
* fadump_reserve_mem(). No need to check this here as
* cma_init_reserved_mem() already checks for overlap.
* Here we give the aligned chunk of this reserved memory to CMA.
*/
base = fw_dump.reserve_dump_area_start;
size = fw_dump.boot_memory_size;
end = base + size;

base = ALIGN(base, CMA_MIN_ALIGNMENT_BYTES);
end = ALIGN_DOWN(end, CMA_MIN_ALIGNMENT_BYTES);
size = end - base;

if (end <= base) {
pr_warn("%s: Too less memory to give to CMA\n", __func__);
return;
}

rc = cma_init_reserved_mem(base, size, 0, "fadump_cma", &fadump_cma);
if (rc) {
Expand All @@ -116,11 +132,12 @@ static void __init fadump_cma_init(void)
/*
* So we now have successfully initialized cma area for fadump.
*/
pr_info("Initialized 0x%lx bytes cma area at %ldMB from 0x%lx "
pr_info("Initialized [0x%llx, %luMB] cma area from [0x%lx, %luMB] "
"bytes of memory reserved for firmware-assisted dump\n",
cma_get_size(fadump_cma),
(unsigned long)cma_get_base(fadump_cma) >> 20,
fw_dump.reserve_dump_area_size);
cma_get_base(fadump_cma), cma_get_size(fadump_cma) >> 20,
fw_dump.reserve_dump_area_start,
fw_dump.boot_memory_size >> 20);
return;
}
#else
static void __init fadump_cma_init(void) { }
Expand Down Expand Up @@ -553,13 +570,6 @@ int __init fadump_reserve_mem(void)
if (!fw_dump.dump_active) {
fw_dump.boot_memory_size =
PAGE_ALIGN(fadump_calculate_reserve_size());
#ifdef CONFIG_CMA
if (!fw_dump.nocma) {
fw_dump.boot_memory_size =
ALIGN(fw_dump.boot_memory_size,
CMA_MIN_ALIGNMENT_BYTES);
}
#endif

bootmem_min = fw_dump.ops->fadump_get_bootmem_min();
if (fw_dump.boot_memory_size < bootmem_min) {
Expand Down

0 comments on commit 6faeac5

Please sign in to comment.