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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: CFF5240010 X-Stat-Signature: emahfnufkrjmcht1t6mto7ygf8chrhtf X-HE-Tag: 1707980305-20072 X-HE-Meta: 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 4+nP3Gsq 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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 Wed, Feb 14, 2024 at 12:53:42PM -0800, Alexei Starovoitov wrote: > On Wed, Feb 14, 2024 at 12:36 AM Christoph Hellwig wrote: > > > > NAK. Please > > What is the alternative? > Remember, maintainers cannot tell developers "go away". > They must suggest a different path. That criteria is something you've made up. Telling that something is not ok is the most important job of not just maintainers but all developers. Maybe start with a description of the problem you're solving and why you think it matters and needs different APIs. > . get_vm_area - external > . free_vm_area - EXPORT_SYMBOL_GPL > . vunmap_range - external > . vmalloc_to_page - EXPORT_SYMBOL > . apply_to_page_range - EXPORT_SYMBOL_GPL > > and the last one is pretty much equivalent to vmap_pages_range, > hence I'm surprised by push back to make vmap_pages_range available to bpf. And the last we've been trying to get rid of by ages because we don't want random modules to > > > For example, there is the public ioremap_page_range(), which is used > > > to map device memory into addressable kernel space. > > > > It's not really public. It's a helper for the ioremap implementation > > which really should not be arch specific to start with and are in > > the process of beeing consolidatd into common code. > > Any link to such consolidation of ioremap ? I couldn't find one. Second hit on google: https://lore.kernel.org/lkml/20230609075528.9390-1-bhe@redhat.com/T/ > I surely don't want bpf_arena to cause headaches to mm folks. > > Anyway, ioremap_page_range() was just an example. > I could have used vmap() as an equivalent example. > vmap is EXPORT_SYMBOL, btw. vmap is a good well defined API. vmap_pages_range is not. > What bpf_arena needs is pretty much vmap(), but instead of > allocating all pages in advance, allocate them and insert on demand. So propose an API that does that instead of exposing random low-level details.