[PATCH v8 07/25] arm64: hibernate: remove gotos as they are not needed

From: Pavel Tatashin
Date: Wed Dec 04 2019 - 11:00:00 EST


Usually, gotos are used to handle cleanup after exception, but in case of
create_safe_exec_page and swsusp_arch_resume there are no clean-ups. So,
simply return the errors directly.

Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Reviewed-by: James Morse <james.morse@xxxxxxx>
---
arch/arm64/kernel/hibernate.c | 49 ++++++++++++-----------------------
1 file changed, 17 insertions(+), 32 deletions(-)

diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c
index 34297716643f..83c41a2f8400 100644
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -198,7 +198,6 @@ static int create_safe_exec_page(void *src_start, size_t length,
unsigned long dst_addr,
phys_addr_t *phys_dst_addr)
{
- int rc = 0;
pgd_t *trans_pgd;
pgd_t *pgdp;
pud_t *pudp;
@@ -206,47 +205,37 @@ static int create_safe_exec_page(void *src_start, size_t length,
pte_t *ptep;
unsigned long dst = get_safe_page(GFP_ATOMIC);

- if (!dst) {
- rc = -ENOMEM;
- goto out;
- }
+ if (!dst)
+ return -ENOMEM;

memcpy((void *)dst, src_start, length);
__flush_icache_range(dst, dst + length);

trans_pgd = (void *)get_safe_page(GFP_ATOMIC);
- if (!trans_pgd) {
- rc = -ENOMEM;
- goto out;
- }
+ if (!trans_pgd)
+ return -ENOMEM;

pgdp = pgd_offset_raw(trans_pgd, dst_addr);
if (pgd_none(READ_ONCE(*pgdp))) {
pudp = (void *)get_safe_page(GFP_ATOMIC);
- if (!pudp) {
- rc = -ENOMEM;
- goto out;
- }
+ if (!pudp)
+ return -ENOMEM;
pgd_populate(&init_mm, pgdp, pudp);
}

pudp = pud_offset(pgdp, dst_addr);
if (pud_none(READ_ONCE(*pudp))) {
pmdp = (void *)get_safe_page(GFP_ATOMIC);
- if (!pmdp) {
- rc = -ENOMEM;
- goto out;
- }
+ if (!pmdp)
+ return -ENOMEM;
pud_populate(&init_mm, pudp, pmdp);
}

pmdp = pmd_offset(pudp, dst_addr);
if (pmd_none(READ_ONCE(*pmdp))) {
ptep = (void *)get_safe_page(GFP_ATOMIC);
- if (!ptep) {
- rc = -ENOMEM;
- goto out;
- }
+ if (!ptep)
+ return -ENOMEM;
pmd_populate_kernel(&init_mm, pmdp, ptep);
}

@@ -272,8 +261,7 @@ static int create_safe_exec_page(void *src_start, size_t length,

*phys_dst_addr = virt_to_phys((void *)dst);

-out:
- return rc;
+ return 0;
}

#define dcache_clean_range(start, end) __flush_dcache_area(start, (end - start))
@@ -482,7 +470,7 @@ static int copy_page_tables(pgd_t *dst_pgdp, unsigned long start,
*/
int swsusp_arch_resume(void)
{
- int rc = 0;
+ int rc;
void *zero_page;
size_t exit_size;
pgd_t *tmp_pg_dir;
@@ -498,12 +486,11 @@ int swsusp_arch_resume(void)
tmp_pg_dir = (pgd_t *)get_safe_page(GFP_ATOMIC);
if (!tmp_pg_dir) {
pr_err("Failed to allocate memory for temporary page tables.\n");
- rc = -ENOMEM;
- goto out;
+ return -ENOMEM;
}
rc = copy_page_tables(tmp_pg_dir, PAGE_OFFSET, PAGE_END);
if (rc)
- goto out;
+ return rc;

/*
* We need a zero page that is zero before & after resume in order to
@@ -512,8 +499,7 @@ int swsusp_arch_resume(void)
zero_page = (void *)get_safe_page(GFP_ATOMIC);
if (!zero_page) {
pr_err("Failed to allocate zero page.\n");
- rc = -ENOMEM;
- goto out;
+ return -ENOMEM;
}

/*
@@ -531,7 +517,7 @@ int swsusp_arch_resume(void)
&phys_hibernate_exit);
if (rc) {
pr_err("Failed to create safe executable page for hibernate_exit code.\n");
- goto out;
+ return rc;
}

/*
@@ -558,8 +544,7 @@ int swsusp_arch_resume(void)
resume_hdr.reenter_kernel, restore_pblist,
resume_hdr.__hyp_stub_vectors, virt_to_phys(zero_page));

-out:
- return rc;
+ return 0;
}

int hibernate_resume_nonboot_cpu_disable(void)
--
2.24.0