[v5 PATCH 14/14] ubifs: Pass folios to acomp

[Zhihao Cheng]

在 2025/3/15 18:30, Herbert Xu 写道:
> As the acomp interface supports folios, use that instead of mapping
> the data in ubifs.
> 
> Signed-off-by: Herbert Xu <herbert at gondor.apana.org.au>
> ---
>   fs/ubifs/compress.c | 106 +++++++++++++++++++++++++++++++++++++++++++-
>   fs/ubifs/file.c     |  74 +++++++++++--------------------
>   fs/ubifs/journal.c  |   9 ++--
>   fs/ubifs/ubifs.h    |  11 ++++-
>   4 files changed, 145 insertions(+), 55 deletions(-)


Tested-by: Zhihao Cheng <chengzhihao1 at huawei.com> # For xfstests

> 
> diff --git a/fs/ubifs/compress.c b/fs/ubifs/compress.c
> index a241ba01c9a8..ea6f06adcd43 100644
> --- a/fs/ubifs/compress.c
> +++ b/fs/ubifs/compress.c
> @@ -16,6 +16,7 @@
>    */
>   
>   #include <crypto/acompress.h>
> +#include <linux/highmem.h>
>   #include "ubifs.h"
>   
>   /* Fake description object for the "none" compressor */
> @@ -126,7 +127,7 @@ void ubifs_compress(const struct ubifs_info *c, const void *in_buf,
>   	{
>   		ACOMP_REQUEST_ALLOC(req, compr->cc, GFP_NOFS | __GFP_NOWARN);
>   
> -		acomp_request_set_src_nondma(req, in_buf, in_len);
> +		acomp_request_set_src_dma(req, in_buf, in_len);

Why not merging it into patch 13?
>   		err = ubifs_compress_req(c, req, out_buf, out_len, compr->name);
>   	}
>   
> @@ -141,6 +142,58 @@ void ubifs_compress(const struct ubifs_info *c, const void *in_buf,
>   	*compr_type = UBIFS_COMPR_NONE;
>   }
>   
> +/**
> + * ubifs_compress_folio - compress folio.
> + * @c: UBIFS file-system description object
> + * @in_folio: data to compress
> + * @in_offset: offset into @in_folio
> + * @in_len: length of the data to compress
> + * @out_buf: output buffer where compressed data should be stored
> + * @out_len: output buffer length is returned here
> + * @compr_type: type of compression to use on enter, actually used compression
> + *              type on exit
> + *
> + * This function compresses input folio @in_folio of length @in_len and
> + * stores the result in the output buffer @out_buf and the resulting length
> + * in @out_len. If the input buffer does not compress, it is just copied
> + * to the @out_buf. The same happens if @compr_type is %UBIFS_COMPR_NONE
> + * or if compression error occurred.
> + *
> + * Note, if the input buffer was not compressed, it is copied to the output
> + * buffer and %UBIFS_COMPR_NONE is returned in @compr_type.
> + */
> +void ubifs_compress_folio(const struct ubifs_info *c, struct folio *in_folio,
> +			  size_t in_offset, int in_len, void *out_buf,
> +			  int *out_len, int *compr_type)
> +{
> +	int err;
> +	struct ubifs_compressor *compr = ubifs_compressors[*compr_type];
> +
> +	if (*compr_type == UBIFS_COMPR_NONE)
> +		goto no_compr;
> +
> +	/* If the input data is small, do not even try to compress it */
> +	if (in_len < UBIFS_MIN_COMPR_LEN)
> +		goto no_compr;
> +
> +	{
> +		ACOMP_REQUEST_ALLOC(req, compr->cc, GFP_NOFS | __GFP_NOWARN);
> +
> +		acomp_request_set_src_folio(req, in_folio, in_offset, in_len);
> +		err = ubifs_compress_req(c, req, out_buf, out_len, compr->name);
> +	}
> +
> +	if (err)
> +		goto no_compr;
> +
> +	return;
> +
> +no_compr:
> +	memcpy_from_folio(out_buf, in_folio, in_offset, in_len);
> +	*out_len = in_len;
> +	*compr_type = UBIFS_COMPR_NONE;
> +}
> +
>   static int ubifs_decompress_req(const struct ubifs_info *c,
>   				struct acomp_req *req,
>   				const void *in_buf, int in_len, int *out_len,
> @@ -205,7 +258,56 @@ int ubifs_decompress(const struct ubifs_info *c, const void *in_buf,
>   	{
>   		ACOMP_REQUEST_ALLOC(req, compr->cc, GFP_NOFS | __GFP_NOWARN);
>   
> -		acomp_request_set_dst_nondma(req, out_buf, *out_len);
> +		acomp_request_set_dst_dma(req, out_buf, *out_len);

Same as the suggestion above.
> +		return ubifs_decompress_req(c, req, in_buf, in_len, out_len,
> +					    compr->name);
> +	}
> +}
> +
> +/**
> + * ubifs_decompress_folio - decompress folio.
> + * @c: UBIFS file-system description object
> + * @in_buf: data to decompress
> + * @in_len: length of the data to decompress
> + * @out_folio: output folio where decompressed data should
> + * @out_offset: offset into @out_folio
> + * @out_len: output length is returned here
> + * @compr_type: type of compression
> + *
> + * This function decompresses data from buffer @in_buf into folio
> + * @out_folio.  The length of the uncompressed data is returned in
> + * @out_len.  This functions returns %0 on success or a negative error
> + * code on failure.
> + */
> +int ubifs_decompress_folio(const struct ubifs_info *c, const void *in_buf,
> +			   int in_len, struct folio *out_folio,
> +			   size_t out_offset, int *out_len, int compr_type)
> +{
> +	struct ubifs_compressor *compr;
> +
> +	if (unlikely(compr_type < 0 || compr_type >= UBIFS_COMPR_TYPES_CNT)) {
> +		ubifs_err(c, "invalid compression type %d", compr_type);
> +		return -EINVAL;
> +	}
> +
> +	compr = ubifs_compressors[compr_type];
> +
> +	if (unlikely(!compr->capi_name)) {
> +		ubifs_err(c, "%s compression is not compiled in", compr->name);
> +		return -EINVAL;
> +	}
> +
> +	if (compr_type == UBIFS_COMPR_NONE) {
> +		memcpy_to_folio(out_folio, out_offset, in_buf, in_len);
> +		*out_len = in_len;
> +		return 0;
> +	}
> +
> +	{
> +		ACOMP_REQUEST_ALLOC(req, compr->cc, GFP_NOFS | __GFP_NOWARN);
> +
> +		acomp_request_set_dst_folio(req, out_folio, out_offset,
> +					    *out_len);
>   		return ubifs_decompress_req(c, req, in_buf, in_len, out_len,
>   					    compr->name);
>   	}