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Date:   Thu, 8 Jun 2023 14:37:34 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Luis Chamberlain <mcgrof@kernel.org>
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Subject: Re: [RFC 4/4] bdev: extend bdev inode with it's own super_block
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References: <20230608032404.1887046-1-mcgrof@kernel.org>
 <20230608032404.1887046-5-mcgrof@kernel.org>
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On Wed, Jun 07, 2023 at 08:24:04PM -0700, Luis Chamberlain wrote:
> We currently share a single super_block for the block device cache,
> each block device corresponds to one inode on that super_block. This
> implicates sharing one aops operation though, and in the near future
> we want to be able to instead support using iomap on the super_block
> for different block devices.

> -struct super_block *blockdev_superblock __read_mostly;

Did we consider adding

+struct super_block *blockdev_sb_iomap __read_mostly;

and then considering only two superblocks instead of having a list of
all bdevs?