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[82.11.51.62]) by smtp.gmail.com with ESMTPSA id fj12-20020a05600c0c8c00b003ef67848a21sm5560213wmb.13.2023.04.06.08.14.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 06 Apr 2023 08:14:45 -0700 (PDT) From: Lucas Tanure To: Rob Herring , Frank Rowand , Mike Rapoport , Andrew Morton Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, jbrunet@baylibre.com, linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, martin.blumenstingl@googlemail.com, narmstrong@baylibre.com, stefan@agner.ch, Lucas Tanure Subject: [PATCH 1/2] memblock: Differentiate regions overlap from both regions being the same Date: Thu, 6 Apr 2023 16:14:28 +0100 Message-Id: <20230406151429.524591-2-tanure@linux.com> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230406151429.524591-1-tanure@linux.com> References: <20230406151429.524591-1-tanure@linux.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Add support for memblock_addrs_overlap to return a different value when both regions are exactly the same region, where base and size are equal between the regions. Signed-off-by: Lucas Tanure --- include/linux/memblock.h | 18 +++++++++++++++--- mm/memblock.c | 37 ++++++++++++++++++++++++------------- 2 files changed, 39 insertions(+), 16 deletions(-) diff --git a/include/linux/memblock.h b/include/linux/memblock.h index 50ad19662a32..c7ba8b01a637 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -49,6 +49,18 @@ enum memblock_flags { MEMBLOCK_DRIVER_MANAGED =3D 0x8, /* always detected via a driver */ }; =20 +/** + * enum memblock_overlap_type - result of comparison between two memory re= gions + * @MEMBLOCK_NO_OVERLAPS: there is no overlap between the two regions + * @MEMBLOCK_OVERLAPS: the two regions overlap each other, but are not the= same + * @MEMBLOCK_EQUAL: both bases and sizes are equal, so the two regions are= exactly the same + */ +enum memblock_overlap_type { + MEMBLOCK_NO_OVERLAPS, + MEMBLOCK_OVERLAPS, + MEMBLOCK_EQUAL, +}; + /** * struct memblock_region - represents a memory region * @base: base address of the region @@ -118,8 +130,8 @@ int memblock_reserve(phys_addr_t base, phys_addr_t size= ); int memblock_physmem_add(phys_addr_t base, phys_addr_t size); #endif void memblock_trim_memory(phys_addr_t align); -bool memblock_overlaps_region(struct memblock_type *type, - phys_addr_t base, phys_addr_t size); +unsigned int memblock_overlaps_region(struct memblock_type *type, + phys_addr_t base, phys_addr_t size); int memblock_mark_hotplug(phys_addr_t base, phys_addr_t size); int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size); int memblock_mark_mirror(phys_addr_t base, phys_addr_t size); @@ -486,7 +498,7 @@ bool memblock_is_memory(phys_addr_t addr); bool memblock_is_map_memory(phys_addr_t addr); bool memblock_is_region_memory(phys_addr_t base, phys_addr_t size); bool memblock_is_reserved(phys_addr_t addr); -bool memblock_is_region_reserved(phys_addr_t base, phys_addr_t size); +unsigned int memblock_is_region_reserved(phys_addr_t base, phys_addr_t siz= e); =20 void memblock_dump_all(void); =20 diff --git a/mm/memblock.c b/mm/memblock.c index 25fd0626a9e7..948cc1bc3edf 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -175,24 +175,33 @@ static inline phys_addr_t memblock_cap_size(phys_addr= _t base, phys_addr_t *size) /* * Address comparison utilities */ -static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t ba= se1, phys_addr_t size1, - phys_addr_t base2, phys_addr_t size2) +static unsigned int __init_memblock memblock_addrs_overlap(phys_addr_t bas= e1, phys_addr_t size1, + phys_addr_t base2, phys_addr_t size2) { - return ((base1 < (base2 + size2)) && (base2 < (base1 + size1))); + if (base1 =3D=3D base2 && size1 =3D=3D size2) + return MEMBLOCK_EQUAL; + + if ((base1 < (base2 + size2)) && (base2 < (base1 + size1))) + return MEMBLOCK_OVERLAPS; + + return MEMBLOCK_NO_OVERLAPS; } =20 -bool __init_memblock memblock_overlaps_region(struct memblock_type *type, - phys_addr_t base, phys_addr_t size) +unsigned int __init_memblock memblock_overlaps_region(struct memblock_type= *type, + phys_addr_t base, phys_addr_t size) { - unsigned long i; + unsigned long i, ret; =20 memblock_cap_size(base, &size); =20 - for (i =3D 0; i < type->cnt; i++) - if (memblock_addrs_overlap(base, size, type->regions[i].base, - type->regions[i].size)) - break; - return i < type->cnt; + for (i =3D 0; i < type->cnt; i++) { + ret =3D memblock_addrs_overlap(base, size, type->regions[i].base, + type->regions[i].size); + if (ret) + return ret; + } + + return MEMBLOCK_NO_OVERLAPS; } =20 /** @@ -1857,9 +1866,11 @@ bool __init_memblock memblock_is_region_memory(phys_= addr_t base, phys_addr_t siz * memory block. * * Return: - * True if they intersect, false if not. + * MEMBLOCK_NO_OVERLAPS if there is no intersection, + * MEMBLOCK_OVERLAPS if they only intersect, + * MEMBLOCK_EQUAL if the region matches base and size to an reserved memor= y. */ -bool __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_ad= dr_t size) +unsigned int __init_memblock memblock_is_region_reserved(phys_addr_t base,= phys_addr_t size) { return memblock_overlaps_region(&memblock.reserved, base, size); } --=20 2.40.0