linux-kernel - Re: [PATCH v2] Documentation/mm: Add information about kmap_local

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Sun, 02 Jul 2023 15:05:09 +0200
From:   "Fabio M. De Francesco" <fmdefrancesco@...il.com>
To:     Matthew Wilcox <willy@...radead.org>,
        Randy Dunlap <rdunlap@...radead.org>
Cc:     Jonathan Corbet <corbet@....net>,
        Andrew Morton <akpm@...ux-foundation.org>,
        "Mike Rapoport (IBM)" <rppt@...nel.org>,
        Deming Wang <wangdeming@...pur.com>,
        Ira Weiny <ira.weiny@...el.com>, linux-doc@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        Catalin Marinas <catalin.marinas@....com>,
        Mike Rapoport <rppt@...ux.ibm.com>,
        Peter Collingbourne <pcc@...gle.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
        Thomas Gleixner <tglx@...utronix.de>,
        Vlastimil Babka <vbabka@...e.cz>, Will Deacon <will@...nel.org>
Subject: Re: [PATCH v2] Documentation/mm: Add information about kmap_local_folio()

On domenica 2 luglio 2023 01:59:04 CEST Randy Dunlap wrote:
> On 7/1/23 16:54, Matthew Wilcox wrote:
> > On Sat, Jul 01, 2023 at 08:21:20AM -0700, Randy Dunlap wrote:
> >>> -* kmap_local_page().  This function is used to require short term
> >>> mappings.
> >>> -  It can be invoked from any context (including interrupts) but the
> >>> mappings
> >>> -  can only be used in the context which acquired them.
> >>> -
> >>> -  This function should always be used, whereas kmap_atomic() and kmap()
> >>> have
> >>> +* kmap_local_page(), kmap_local_folio() - These functions are used to
> >>> require
> >>>  
> >> acquire?
> > 
> > "create" might be better?
> 
> Yes, that's good.

Agreed.
However, I can send next version only by week 28th.

Thanks,

Fabio

P.S.: Actually I meant "to request". Unfortunately, "to request" and "to 
require" may have the same translation in Italian, my native language.

I preferred to not use "acquire" because it is re-used few lines below. So I 
thought that "to request short term mappings" was good (although I wrongly 
confused the different meanings between "to require" and "to request").

Matthew's suggestion to use "create" avoids repetition of "acquire(d)".  

> >>> +  short term mappings. They can be invoked from any context (including
> >>> +  interrupts) but the mappings can only be used in the context which
> >>> acquired +  them. The only differences between them consist in the first
> >>> taking a pointer +  to a struct page and the second taking a pointer to
> >>> struct folio and the byte +  offset within the folio which identifies 
the
> >>> page.
> >> 
> >> --
> >> ~Randy
> 
> --
> ~Randy