Hi, On Tue, May 21, 2019, at 17:52, Takashi Iwai wrote: > On Tue, 21 May 2019 10:37:43 +0200, > Miartus, Adam (Arion Recruitment; ADITG/ESM) wrote: > > > > > On Mon, 20 May 2019 18:51:06 +0200, > > > Miartus, Adam (Arion Recruitment; ADITG/ESM) wrote: > > > > > > > > From: Adam Miartus <amiartus@xxxxxxxxxxxxxx> > > > > > > > > mmap_begin callback is used to copy data from input file to mmaped > > > > buffer > > > > > > > > guard for corner use of api (multiple mmap_begin calls by user) is > > > > introduced to check if next continuous buffer was already overwritten > > > > > > > > buffer is overwritten with input file data only in case of stream > > > > capture > > > > > > > > Signed-off-by: Adam Miartus <amiartus@xxxxxxxxxxxxxx> > > > > Reviewed-by: Timo Wischer <twischer@xxxxxxxxxxxxxx> > > > > > > Can't we copy the data in snd_pcm_file_mmap_commit() just like the > > > playback case? > > > > > > > > > thanks, > > > > > > Takashi > > > > My understanding is that in case of reading data in mmap mode user > > would call mmap_begin, read the buffer and then call mmap_commit. > > > > In this case overwriting the buffer in mmap_commit with data from > > Input file would be too late. > > Hm, OK. I basically hate to add a new ops, but this might be the only > way if we have to implement that. I'm interested in this patch, however the patch is not blasted by list server. Would you please re-post your patchset so that the list server delivers them to subscribers and I can see the contents? > OTOH, is this mmap support mandatory? IOW, is wrapping with the plug > and mmap_emul performance-wise so bad? Regards Takashi Sakamoto _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
