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Date: Mon, 19 Feb 2024 07:25:44 +0100
From: Christoph Hellwig <hch@lst.de>
To: Matthew Wilcox <willy@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>,
	Chandan Babu R <chandan.babu@oracle.com>,
	"Darrick J. Wong" <djwong@kernel.org>,
	Hugh Dickins <hughd@google.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-xfs@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH 05/20] shmem: export shmem_get_folio
Message-ID: <20240219062544.GA4346@lst.de>
References: <20240129143502.189370-1-hch@lst.de> <20240129143502.189370-6-hch@lst.de> <Zc9oxYc-amPs0X3V@casper.infradead.org>
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On Fri, Feb 16, 2024 at 01:53:09PM +0000, Matthew Wilcox wrote:
> I know I gave an R-b on this earlier, but Hugh made me look again, and
> this comment clearly does not reflect what the function does.
> Presumably it returns an errno and sets foliop if it returns 0?

Almost.  With SGP_READ it can set *foliop to NULL and still return 0.

> Also, should this function be called shmem_lock_folio() to mirror
> filemap_lock_folio()?

shmem_get_folio can also allocate (and sometimes zero) a new folio.
Except for the different calling conventions that closest filemap
equivalent is __filemap_get_folio.  For now I'd like to avoid the
bikeshedding on the name and just get the work done.