linux-kernel - Re: [PATCH 1/4] fs/buffer: use sleeping lookup in __getblk

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

Message-ID: <2dati3l5r4u7uypyzrp5r6diuz6fuuhnv673szh7akdz55wbd3@gjexaphlhv7u>
Date: Fri, 16 May 2025 12:11:53 +0200
From: Jan Kara <jack@...e.cz>
To: Davidlohr Bueso <dave@...olabs.net>
Cc: brauner@...nel.org, jack@...e.cz, viro@...iv.linux.org.uk, 
	mcgrof@...nel.org, linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/4] fs/buffer: use sleeping lookup in __getblk_slowpath()

On Thu 15-05-25 10:39:22, Davidlohr Bueso wrote:
> Just as with the fast path, call the lookup variant depending
> on the gfp flags.
> 
> Signed-off-by: Davidlohr Bueso <dave@...olabs.net>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@...e.cz>

								Honza
> ---
>  fs/buffer.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/buffer.c b/fs/buffer.c
> index b8e1e6e325cd..5a4342881f3b 100644
> --- a/fs/buffer.c
> +++ b/fs/buffer.c
> @@ -1122,6 +1122,8 @@ static struct buffer_head *
>  __getblk_slow(struct block_device *bdev, sector_t block,
>  	     unsigned size, gfp_t gfp)
>  {
> +	bool blocking = gfpflags_allow_blocking(gfp);
> +
>  	/* Size must be multiple of hard sectorsize */
>  	if (unlikely(size & (bdev_logical_block_size(bdev)-1) ||
>  			(size < 512 || size > PAGE_SIZE))) {
> @@ -1137,7 +1139,10 @@ __getblk_slow(struct block_device *bdev, sector_t block,
>  	for (;;) {
>  		struct buffer_head *bh;
>  
> -		bh = __find_get_block(bdev, block, size);
> +		if (blocking)
> +			bh = __find_get_block_nonatomic(bdev, block, size);
> +		else
> +			bh = __find_get_block(bdev, block, size);
>  		if (bh)
>  			return bh;
>  
> -- 
> 2.39.5
> 
-- 
Jan Kara <jack@...e.com>
SUSE Labs, CR