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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam10 X-Stat-Signature: 1bpkb77ni5faugdbgiurywbj1y9zxkgo X-Rspamd-Queue-Id: 616A81C0004 X-Rspam-User: X-HE-Tag: 1747023886-708462 X-HE-Meta: U2FsdGVkX1+wOYDDy22EmI3WxqcyT9DLb36kpNBBtc2eCaCNDv2B3UjXM6eHufyUr9XP1XSkcZngCgCVquH68KMZy8OnKCvQ/x9LoWTcMqzVF5d1CAa3B5Y2Syt964UqfsWO9OvJcdo1GkNvkrUmHPPFWAa+AUVsQLjjq7gPNEf+TrvY3tRiCqsI4B0hcvGCspGxzj15EDOixMzaHZzKNUmKUGMf6xliOGrKBX7x1c03uJENSHi0ZhGwx4fCBYIk/O5DjoQCVrCpJZR4v/eigdsogXJlfuUatFi3/VfoZqAnSjAC0nXTQIMU7pZSp+rT6SuXSThq2GuIsCw7mP4TZNEU8hnV9sO5Q2/L/AdQl0BaTPK2F0RgaZz5azpBkLbaBk4P8T8sRhe+MAcOS2h/S5cGUTd65ZKtyiu+x/ehDNVkcs3xBq+rTzTSv97NhaaS8Ev1hBiyULsdCpNSiGfGTqHpNGPTs5caFIVyrFNqX1iE1kf3DxBzvRFknnzeBxYInt0TvyIkNEP+BnmpecoJ3f/mq4JAfnaNS1yN1VzhCcXzQGNkQT5vORRFawMqNGmEosg/SclAmUdxw7iXY2AvPrNUwKE0y5fw1LHwlFVRKz4lnGKznCdScRCbeelghY3hYROxeHrOBnZsuaFti3r4pFKg03kn2p9GC/7i8M5WBQ2X24TD1pPat5vfUwWXEo6KOJfEtK1N0Cq4OLi3SEOkHJEdsgsbGBUygIrh0MBVaw4e2W/BsDJXVUfWY9xqIiUWjMAmc0Qz5LlEtSBKY6JWVzhNO4tN8b4/2Se7ASHWwKXOyhBqLZhCR2JcW+upnPZa06J4VEK/0584MBKEwoh4VYfi2jqc9C8iZlj/nuaSB5QeGiutfLL4iNIhBjkGZUWH8lcveMSDdAdU35sbMRtXREsBKWe0wu2ng/1tdgM1f8CH+vcWE5HxIKNmqcWSL25KrmC2zljV4RyOF1kY3AG GJeBjm9+ 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, May 10, 2025 at 03:53:47PM +0200, Andrew Lunn wrote: > > Random thoughts here until I look at the patches. > > The concept of devices doing DMA + recycling the used buffer > > transcends networking. > > Do you know of any other subsystem which takes a page, splits it into > two, and then uses each half independently for DMA and recycling. A > typical packet is 1514 octets, so you can get two in a page. The mm/dmapool.c code is all about this.