On Tue, 11 Aug 2020 15:17:55 +0200
Joao Marcos Costa <[email protected]> wrote:
> +#if IS_ENABLED(CONFIG_ZSTD)
> +static int sqfs_zstd_decompress(void *dest, unsigned long dest_len,
> + void *source, u32 src_len)
> +{
> + void *workspace;
> + ZSTD_DCtx *ctx;
> + size_t wsize;
> + int ret;
> +
> + wsize = ZSTD_DCtxWorkspaceBound();
So apparently this "workspace" has a constant size, which does not
depend on the size of the input buffer. Correct ?
If that's the case, can we instead allocate it once for all in
sqfs_probe() if the filesystem is zstd-compressed ? I.e perhaps
sqfs_probe() could call a sqfs_decompressor_init() function,
implemented in sqfs_decompressor.c, which will do this sort of
initialization. And of course this memory area would be freed up in
sqfs_close(), calling a sqfs_decompressor_{deinit,cleanup,close}
function.
Best regards,
Thomas
--
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
