From:   Doug Berger <opendmb@gmail.com>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Jonathan Corbet <corbet@lwn.net>, Mike Rapoport <rppt@kernel.org>,
        Borislav Petkov <bp@suse.de>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Randy Dunlap <rdunlap@infradead.org>,
        Neeraj Upadhyay <quic_neeraju@quicinc.com>,
        Damien Le Moal <damien.lemoal@opensource.wdc.com>,
        Kim Phillips <kim.phillips@amd.com>,
        "Steven Rostedt (Google)" <rostedt@goodmis.org>,
        Michal Hocko <mhocko@suse.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
        Mel Gorman <mgorman@suse.de>,
        Muchun Song <songmuchun@bytedance.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        David Hildenbrand <david@redhat.com>,
        Oscar Salvador <osalvador@suse.de>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Sukadev Bhattiprolu <quic_sukadev@quicinc.com>,
        Rik van Riel <riel@surriel.com>,
        Roman Gushchin <guro@fb.com>, Minchan Kim <minchan@kernel.org>,
        Chris Goldsworthy <quic_cgoldswo@quicinc.com>,
        "Georgi Djakov" <quic_c_gdjako@quicinc.com>,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, Doug Berger <opendmb@gmail.com>
Subject: [PATCH v4 6/9] memblock: introduce MEMBLOCK_MOVABLE flag
Date:   Fri, 10 Mar 2023 16:38:52 -0800
Message-Id: <20230311003855.645684-7-opendmb@gmail.com>
In-Reply-To: <20230311003855.645684-1-opendmb@gmail.com>
References: <20230311003855.645684-1-opendmb@gmail.com>
MIME-Version: 1.0
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The MEMBLOCK_MOVABLE flag is introduced to designate a memblock
as only supporting movable allocations by the page allocator.

Signed-off-by: Doug Berger <opendmb@gmail.com>
---
 include/linux/memblock.h |  8 ++++++++
 mm/memblock.c            | 24 ++++++++++++++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 50ad19662a32..8eb3ca32dfa7 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -47,6 +47,7 @@ enum memblock_flags {
 	MEMBLOCK_MIRROR		= 0x2,	/* mirrored region */
 	MEMBLOCK_NOMAP		= 0x4,	/* don't add to kernel direct mapping */
 	MEMBLOCK_DRIVER_MANAGED = 0x8,	/* always detected via a driver */
+	MEMBLOCK_MOVABLE	= 0x10,	/* designated movable block */
 };
 
 /**
@@ -125,6 +126,8 @@ int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size);
 int memblock_mark_mirror(phys_addr_t base, phys_addr_t size);
 int memblock_mark_nomap(phys_addr_t base, phys_addr_t size);
 int memblock_clear_nomap(phys_addr_t base, phys_addr_t size);
+int memblock_mark_movable(phys_addr_t base, phys_addr_t size);
+int memblock_clear_movable(phys_addr_t base, phys_addr_t size);
 
 void memblock_free_all(void);
 void memblock_free(void *ptr, size_t size);
@@ -265,6 +268,11 @@ static inline bool memblock_is_driver_managed(struct memblock_region *m)
 	return m->flags & MEMBLOCK_DRIVER_MANAGED;
 }
 
+static inline bool memblock_is_movable(struct memblock_region *m)
+{
+	return m->flags & MEMBLOCK_MOVABLE;
+}
+
 int memblock_search_pfn_nid(unsigned long pfn, unsigned long *start_pfn,
 			    unsigned long  *end_pfn);
 void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn,
diff --git a/mm/memblock.c b/mm/memblock.c
index 25fd0626a9e7..794a099ec3e2 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -992,6 +992,30 @@ int __init_memblock memblock_clear_nomap(phys_addr_t base, phys_addr_t size)
 	return memblock_setclr_flag(base, size, 0, MEMBLOCK_NOMAP);
 }
 
+/**
+ * memblock_mark_movable - Mark designated movable block with MEMBLOCK_MOVABLE.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_mark_movable(phys_addr_t base, phys_addr_t size)
+{
+	return memblock_setclr_flag(base, size, 1, MEMBLOCK_MOVABLE);
+}
+
+/**
+ * memblock_clear_movable - Clear flag MEMBLOCK_MOVABLE for a specified region.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_clear_movable(phys_addr_t base, phys_addr_t size)
+{
+	return memblock_setclr_flag(base, size, 0, MEMBLOCK_MOVABLE);
+}
+
 static bool should_skip_region(struct memblock_type *type,
 			       struct memblock_region *m,
 			       int nid, int flags)
-- 
2.34.1