We want to stop special casing hugetlb mappings and make them go
through generic channels, so teach arch_get_unmapped_area{_topdown}
to handle those.
sparc specific hugetlb function does not set info.align_offset, and
does not care about adjusting the align_mask for MAP_SHARED cases,
so the same here for compatibility.

Signed-off-by: Oscar Salvador <osalvador@suse.de>
---
 arch/sparc/kernel/sys_sparc_32.c | 17 +++++++++++----
 arch/sparc/kernel/sys_sparc_64.c | 37 +++++++++++++++++++++++++-------
 2 files changed, 42 insertions(+), 12 deletions(-)

diff --git a/arch/sparc/kernel/sys_sparc_32.c b/arch/sparc/kernel/sys_sparc_32.c
index 80822f922e76..959f3c2ca201 100644
--- a/arch/sparc/kernel/sys_sparc_32.c
+++ b/arch/sparc/kernel/sys_sparc_32.c
@@ -23,6 +23,7 @@
 #include <linux/utsname.h>
 #include <linux/smp.h>
 #include <linux/ipc.h>
+#include <linux/hugetlb.h>
 
 #include <linux/uaccess.h>
 #include <asm/unistd.h>
@@ -42,12 +43,16 @@ SYSCALL_DEFINE0(getpagesize)
 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags)
 {
 	struct vm_unmapped_area_info info = {};
+	bool file_hugepage = false;
+
+	if (filp && is_file_hugepages(filp))
+		file_hugepage = true;
 
 	if (flags & MAP_FIXED) {
 		/* We do not accept a shared mapping if it would violate
 		 * cache aliasing constraints.
 		 */
-		if ((flags & MAP_SHARED) &&
+		if (!file_huge_pages && (flags & MAP_SHARED) &&
 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
 			return -EINVAL;
 		return addr;
@@ -62,9 +67,13 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 	info.length = len;
 	info.low_limit = addr;
 	info.high_limit = TASK_SIZE;
-	info.align_mask = (flags & MAP_SHARED) ?
-		(PAGE_MASK & (SHMLBA - 1)) : 0;
-	info.align_offset = pgoff << PAGE_SHIFT;
+	if (!file_hugepage) {
+		info.align_mask = (flags & MAP_SHARED) ?
+			(PAGE_MASK & (SHMLBA - 1)) : 0;
+		info.align_offset = pgoff << PAGE_SHIFT;
+	} else {
+		info.align_mask = huge_page_mask_align(filp);
+	}
 	return vm_unmapped_area(&info);
 }
 
diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index acade309dc2f..c5a284df7b41 100644
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -30,6 +30,7 @@
 #include <linux/context_tracking.h>
 #include <linux/timex.h>
 #include <linux/uaccess.h>
+#include <linux/hugetlb.h>
 
 #include <asm/utrap.h>
 #include <asm/unistd.h>
@@ -87,6 +88,16 @@ static inline unsigned long COLOR_ALIGN(unsigned long addr,
 	return base + off;
 }
 
+static unsigned long get_align_mask(struct file *filp, unsigned long flags)
+{
+	if (filp && is_file_hugepages(filp))
+		return huge_page_mask_align(filp);
+	if (filp || (flags & MAP_SHARED))
+		return PAGE_MASK & (SHMLBA - 1);
+
+	return 0;
+}
+
 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags)
 {
 	struct mm_struct *mm = current->mm;
@@ -94,12 +105,16 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 	unsigned long task_size = TASK_SIZE;
 	int do_color_align;
 	struct vm_unmapped_area_info info = {};
+	bool file_hugepage = false;
+
+	if (filp && is_file_hugepages(filp))
+		file_hugepage = true;
 
 	if (flags & MAP_FIXED) {
 		/* We do not accept a shared mapping if it would violate
 		 * cache aliasing constraints.
 		 */
-		if ((flags & MAP_SHARED) &&
+		if (!file_hugepage && (flags & MAP_SHARED) &&
 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
 			return -EINVAL;
 		return addr;
@@ -111,7 +126,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 		return -ENOMEM;
 
 	do_color_align = 0;
-	if (filp || (flags & MAP_SHARED))
+	if ((filp || (flags & MAP_SHARED)) && !file_hugepage)
 		do_color_align = 1;
 
 	if (addr) {
@@ -129,8 +144,9 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 	info.length = len;
 	info.low_limit = TASK_UNMAPPED_BASE;
 	info.high_limit = min(task_size, VA_EXCLUDE_START);
-	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
-	info.align_offset = pgoff << PAGE_SHIFT;
+	info.align_mask = get_align_mask(filp, flags);
+	if (!file_hugepage)
+		info.align_offset = pgoff << PAGE_SHIFT;
 	addr = vm_unmapped_area(&info);
 
 	if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
@@ -154,15 +170,19 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 	unsigned long addr = addr0;
 	int do_color_align;
 	struct vm_unmapped_area_info info = {};
+	bool file_hugepage = false;
 
 	/* This should only ever run for 32-bit processes.  */
 	BUG_ON(!test_thread_flag(TIF_32BIT));
 
+	if (filp && is_file_hugepages(filp))
+		file_hugepage = true;
+
 	if (flags & MAP_FIXED) {
 		/* We do not accept a shared mapping if it would violate
 		 * cache aliasing constraints.
 		 */
-		if ((flags & MAP_SHARED) &&
+		if (!file_hugepage && (flags & MAP_SHARED) &&
 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
 			return -EINVAL;
 		return addr;
@@ -172,7 +192,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 		return -ENOMEM;
 
 	do_color_align = 0;
-	if (filp || (flags & MAP_SHARED))
+	if ((filp || (flags & MAP_SHARED)) && !file_hugepage)
 		do_color_align = 1;
 
 	/* requesting a specific address */
@@ -192,8 +212,9 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 	info.length = len;
 	info.low_limit = PAGE_SIZE;
 	info.high_limit = mm->mmap_base;
-	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
-	info.align_offset = pgoff << PAGE_SHIFT;
+	info.align_mask = get_align_mask(filp, flags);
+	if (!file_hugepage)
+		info.align_offset = pgoff << PAGE_SHIFT;
 	addr = vm_unmapped_area(&info);
 
 	/*
-- 
2.46.0

Hi Oscar,

kernel test robot noticed the following build errors:

[auto build test ERROR on akpm-mm/mm-everything]
[also build test ERROR on next-20240913]
[cannot apply to s390/features powerpc/next powerpc/fixes deller-parisc/for-next arnd-asm-generic/master linus/master v6.11-rc7]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Oscar-Salvador/mm-mmap-Teach-generic_get_unmapped_area-_topdown-to-handle-hugetlb-mappings/20240910-160312
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/20240910080030.1272373-5-osalvador%40suse.de
patch subject: [PATCH v3 4/9] arch/sparc: Teach arch_get_unmapped_area{_topdown} to handle hugetlb mappings
config: sparc-randconfig-002-20240913 (https://download.01.org/0day-ci/archive/20240913/202409131805.4Dlb536A-lkp@intel.com/config)
compiler: sparc-linux-gcc (GCC) 14.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240913/202409131805.4Dlb536A-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202409131805.4Dlb536A-lkp@intel.com/

All errors (new ones prefixed by >>):

   arch/sparc/kernel/sys_sparc_32.c: In function 'arch_get_unmapped_area':
>> arch/sparc/kernel/sys_sparc_32.c:55:22: error: 'file_huge_pages' undeclared (first use in this function); did you mean 'file_hugepage'?
      55 |                 if (!file_huge_pages && (flags & MAP_SHARED) &&
         |                      ^~~~~~~~~~~~~~~
         |                      file_hugepage
   arch/sparc/kernel/sys_sparc_32.c:55:22: note: each undeclared identifier is reported only once for each function it appears in


vim +55 arch/sparc/kernel/sys_sparc_32.c

    42	
    43	unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags)
    44	{
    45		struct vm_unmapped_area_info info = {};
    46		bool file_hugepage = false;
    47	
    48		if (filp && is_file_hugepages(filp))
    49			file_hugepage = true;
    50	
    51		if (flags & MAP_FIXED) {
    52			/* We do not accept a shared mapping if it would violate
    53			 * cache aliasing constraints.
    54			 */
  > 55			if (!file_huge_pages && (flags & MAP_SHARED) &&
    56			    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
    57				return -EINVAL;
    58			return addr;
    59		}
    60	
    61		/* See asm-sparc/uaccess.h */
    62		if (len > TASK_SIZE - PAGE_SIZE)
    63			return -ENOMEM;
    64		if (!addr)
    65			addr = TASK_UNMAPPED_BASE;
    66	
    67		info.length = len;
    68		info.low_limit = addr;
    69		info.high_limit = TASK_SIZE;
    70		if (!file_hugepage) {
    71			info.align_mask = (flags & MAP_SHARED) ?
    72				(PAGE_MASK & (SHMLBA - 1)) : 0;
    73			info.align_offset = pgoff << PAGE_SHIFT;
    74		} else {
    75			info.align_mask = huge_page_mask_align(filp);
    76		}
    77		return vm_unmapped_area(&info);
    78	}
    79	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki