[RFC v3 1/3] fadump: Refactor and prepare fadump_cma_init for late init

From: Ritesh Harjani (IBM)
Date: Fri Oct 11 2024 - 11:00:30 EST


We anyway don't use any return values from fadump_cma_init(). Since
fadump_reserve_mem() from where fadump_cma_init() gets called today,
already has the required checks.
This patch makes this function return type as void. Let's also handle
extra cases like return if fadump_supported is false or dump_active, so
that in later patches we can call fadump_cma_init() separately from
setup_arch().

Acked-by: Hari Bathini <hbathini@xxxxxxxxxxxxx>
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>
---
v2 -> v3: Separated the series into 2 as discussed in v2.
[v2]: https://lore.kernel.org/linuxppc-dev/cover.1728585512.git.ritesh.list@xxxxxxxxx/

arch/powerpc/kernel/fadump.c | 23 +++++++++--------------
1 file changed, 9 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index a612e7513a4f..162327d66982 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -78,27 +78,23 @@ static struct cma *fadump_cma;
* But for some reason even if it fails we still have the memory reservation
* with us and we can still continue doing fadump.
*/
-static int __init fadump_cma_init(void)
+static void __init fadump_cma_init(void)
{
unsigned long long base, size;
int rc;

- if (!fw_dump.fadump_enabled)
- return 0;
-
+ if (!fw_dump.fadump_supported || !fw_dump.fadump_enabled ||
+ fw_dump.dump_active)
+ return;
/*
* Do not use CMA if user has provided fadump=nocma kernel parameter.
- * Return 1 to continue with fadump old behaviour.
*/
- if (fw_dump.nocma)
- return 1;
+ if (fw_dump.nocma || !fw_dump.boot_memory_size)
+ return;

base = fw_dump.reserve_dump_area_start;
size = fw_dump.boot_memory_size;

- if (!size)
- return 0;
-
rc = cma_init_reserved_mem(base, size, 0, "fadump_cma", &fadump_cma);
if (rc) {
pr_err("Failed to init cma area for firmware-assisted dump,%d\n", rc);
@@ -108,7 +104,7 @@ static int __init fadump_cma_init(void)
* blocked from production system usage. Hence return 1,
* so that we can continue with fadump.
*/
- return 1;
+ return;
}

/*
@@ -125,10 +121,9 @@ static int __init fadump_cma_init(void)
cma_get_size(fadump_cma),
(unsigned long)cma_get_base(fadump_cma) >> 20,
fw_dump.reserve_dump_area_size);
- return 1;
}
#else
-static int __init fadump_cma_init(void) { return 1; }
+static void __init fadump_cma_init(void) { }
#endif /* CONFIG_CMA */

/*
@@ -638,7 +633,7 @@ int __init fadump_reserve_mem(void)
pr_info("Reserved %lldMB of memory at %#016llx (System RAM: %lldMB)\n",
(size >> 20), base, (memblock_phys_mem_size() >> 20));

- ret = fadump_cma_init();
+ fadump_cma_init();
}

return ret;
--
2.46.0