From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 81738CA0ED1 for ; Fri, 15 Aug 2025 12:12:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E68356B009F; Fri, 15 Aug 2025 08:12:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E182D8E01EC; Fri, 15 Aug 2025 08:12:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D54A86B00A1; Fri, 15 Aug 2025 08:12:12 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id C7C4E6B009F for ; Fri, 15 Aug 2025 08:12:12 -0400 (EDT) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 6FE20C012D for ; 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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 9241D1C0007 X-Stat-Signature: ek4mdqnppex63nnofoxkmrbgxra4sf9e X-Rspam-User: X-HE-Tag: 1755259930-408229 X-HE-Meta: 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 oy9T0hej 7kWzbe6pMLHN78K+Prr8EVwCemIIM7WxSa7KaR/qaySqV3AXfiZAtuXH88nblcen/u1ReC6Zndwwp/2F4MH9xFqwel+rGeTqCnUSjJ3tuZfsFbTxuqfcNwvcPTIHZfdJQ5jEuq/OW2x8manOlzU91O6JY/HBDwYvgTQo16kTK3tVClS8ZQ2x4/sMZrT9drAdScGr8cAmo5BEDG98rCvP7xyMpjQ== 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 15/08/2025 09:30, Dev Jain wrote: > > On 13/08/25 8:26 pm, Chaitanya S Prakash wrote: >> [-------snip-------------] >>   -static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, >> +static int __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, >>                    unsigned long virt, phys_addr_t size, >>                    pgprot_t prot, >>                    phys_addr_t (*pgtable_alloc)(enum pgtable_type), >>                    int flags) >>   { >> +    int ret = 0; >> + >>       mutex_lock(&fixmap_lock); >> -    __create_pgd_mapping_locked(pgdir, phys, virt, size, prot, >> -                    pgtable_alloc, flags); >> +    ret = __create_pgd_mapping_locked(pgdir, phys, virt, size, prot, >> +                      pgtable_alloc, flags); >>       mutex_unlock(&fixmap_lock); >> + >> +    return ret; >> +} >> + >> +static void ___create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, >> +                  unsigned long virt, phys_addr_t size, >> +                  pgprot_t prot, >> +                  phys_addr_t (*pgtable_alloc)(enum pgtable_type), >> +                  int flags) >> +{ >> +    int ret = 0; >> + >> +    ret = __create_pgd_mapping(pgdir, phys, virt, size, prot, >> pgtable_alloc, >> +                   flags); >> +    BUG_ON(ret); >>   } > > A triple underscore calling a double underscore isn't natural to > reason about. Also not the most readable (easy to confuse the two). > Since this is the function which must succeed, how does > "must_create_pgd_mapping()" > sound? "must" isn't a prefix that is commonly used in that sense, not sure this is very clear. Another idea that comes to mind is early_create_pgd_mapping() - the BUG_ON() being justified by the fact that early errors are not recoverable. On a related note, it would be possible to return an error from create_pgd_mapping() and create_mapping_noalloc() as their callers already have error paths. That would be a bit cleaner but I don't know if it's worth the hassle. - Kevin