[ALSA patch] [PATCH - alsa-lib 3/4] pcm: add mmap_begin callback to snd_pcm_fast_ops_t api
Miartus, Adam (Arion Recruitment; ADITG/ESM)
amiartus at de.adit-jv.com
Mon May 20 18:50:36 CEST 2019
From: Adam Miartus <amiartus at de.adit-jv.com>
main motivation for adding the callback is to use it to enable operation on mmaped buffer before user access for pcm_file plugin
support for MMAP read access with masking by data from input file is not implemented for pcm_file plugin, by adding this callback implementing such feature can be done by rewriting next continuous portion of buffer on each mmap_begin call
plugins like softvol use pcm_plugin interface and overwrite the buffer by looping around it in avail_update callback, this patch hopes to simplify the task by adding new api callback, removing the need for rewriting pcm_file (to use pcm_plugin callbacks) and careful checking when looping around whole mmaped buffer
Signed-off-by: Adam Miartus <amiartus at de.adit-jv.com>
Reviewed-by: Timo Wischer <twischer at de.adit-jv.com>
diff --git a/src/pcm/pcm.c b/src/pcm/pcm.c index 3a71d79..323926e 100644
--- a/src/pcm/pcm.c
+++ b/src/pcm/pcm.c
@@ -7129,7 +7129,13 @@ int __snd_pcm_mmap_begin(snd_pcm_t *pcm, const snd_pcm_channel_area_t **areas,
snd_pcm_uframes_t f;
snd_pcm_uframes_t avail;
const snd_pcm_channel_area_t *xareas;
+
assert(pcm && areas && offset && frames);
+
+ if (pcm->fast_ops->mmap_begin)
+ return pcm->fast_ops->mmap_begin(pcm->fast_op_arg, areas, offset,
+frames);
+
+ /* fallback for plugins that do not specify new callback */
xareas = snd_pcm_mmap_areas(pcm);
if (xareas == NULL)
return -EBADFD;
diff --git a/src/pcm/pcm_dmix.c b/src/pcm/pcm_dmix.c index 274726e..96049e0 100644
--- a/src/pcm/pcm_dmix.c
+++ b/src/pcm/pcm_dmix.c
@@ -990,6 +990,7 @@ static const snd_pcm_fast_ops_t snd_pcm_dmix_fast_ops = {
.poll_descriptors = snd_pcm_direct_poll_descriptors,
.poll_descriptors_count = NULL,
.poll_revents = snd_pcm_dmix_poll_revents,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_dshare.c b/src/pcm/pcm_dshare.c index b75809c..328ef83 100644
--- a/src/pcm/pcm_dshare.c
+++ b/src/pcm/pcm_dshare.c
@@ -667,6 +667,7 @@ static const snd_pcm_fast_ops_t snd_pcm_dshare_fast_ops = {
.poll_descriptors = snd_pcm_direct_poll_descriptors,
.poll_descriptors_count = NULL,
.poll_revents = snd_pcm_direct_poll_revents,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_dsnoop.c b/src/pcm/pcm_dsnoop.c index 58b1e53..5b9d9f5 100644
--- a/src/pcm/pcm_dsnoop.c
+++ b/src/pcm/pcm_dsnoop.c
@@ -544,6 +544,7 @@ static const snd_pcm_fast_ops_t snd_pcm_dsnoop_fast_ops = {
.poll_descriptors = snd_pcm_direct_poll_descriptors,
.poll_descriptors_count = NULL,
.poll_revents = snd_pcm_direct_poll_revents,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_file.c b/src/pcm/pcm_file.c index 29ab2fb..c8f4c84 100644
--- a/src/pcm/pcm_file.c
+++ b/src/pcm/pcm_file.c
@@ -771,6 +771,7 @@ static const snd_pcm_fast_ops_t snd_pcm_file_fast_ops = {
.poll_descriptors = snd_pcm_generic_poll_descriptors,
.poll_revents = snd_pcm_generic_poll_revents,
.htimestamp = snd_pcm_generic_htimestamp,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_generic.h b/src/pcm/pcm_generic.h index dfbe21a..683e60b 100644
--- a/src/pcm/pcm_generic.h
+++ b/src/pcm/pcm_generic.h
@@ -161,4 +161,3 @@ snd_pcm_chmap_query_t **snd_pcm_generic_query_chmaps(snd_pcm_t *pcm); snd_pcm_chmap_t *snd_pcm_generic_get_chmap(snd_pcm_t *pcm); int snd_pcm_generic_set_chmap(snd_pcm_t *pcm, const snd_pcm_chmap_t *map); int snd_pcm_generic_may_wait_for_avail_min(snd_pcm_t *pcm, snd_pcm_uframes_t avail);
-
diff --git a/src/pcm/pcm_hooks.c b/src/pcm/pcm_hooks.c index 4416d36..14396fa 100644
--- a/src/pcm/pcm_hooks.c
+++ b/src/pcm/pcm_hooks.c
@@ -200,6 +200,7 @@ static const snd_pcm_fast_ops_t snd_pcm_hooks_fast_ops = {
.poll_descriptors = snd_pcm_generic_poll_descriptors,
.poll_revents = snd_pcm_generic_poll_revents,
.may_wait_for_avail_min = snd_pcm_generic_may_wait_for_avail_min,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_hw.c b/src/pcm/pcm_hw.c index 91370a8..8ee1d69 100644
--- a/src/pcm/pcm_hw.c
+++ b/src/pcm/pcm_hw.c
@@ -1481,6 +1481,7 @@ static const snd_pcm_fast_ops_t snd_pcm_hw_fast_ops = {
.poll_descriptors = NULL,
.poll_descriptors_count = NULL,
.poll_revents = NULL,
+ .mmap_begin = NULL,
};
static const snd_pcm_fast_ops_t snd_pcm_hw_fast_ops_timer = { @@ -1512,6 +1513,7 @@ static const snd_pcm_fast_ops_t snd_pcm_hw_fast_ops_timer = {
.poll_descriptors = snd_pcm_hw_poll_descriptors,
.poll_descriptors_count = snd_pcm_hw_poll_descriptors_count,
.poll_revents = snd_pcm_hw_poll_revents,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_ioplug.c b/src/pcm/pcm_ioplug.c index a437ca3..3e19499 100644
--- a/src/pcm/pcm_ioplug.c
+++ b/src/pcm/pcm_ioplug.c
@@ -940,6 +940,7 @@ static const snd_pcm_fast_ops_t snd_pcm_ioplug_fast_ops = {
.poll_descriptors_count = snd_pcm_ioplug_poll_descriptors_count,
.poll_descriptors = snd_pcm_ioplug_poll_descriptors,
.poll_revents = snd_pcm_ioplug_poll_revents,
+ .mmap_begin = NULL,
};
#endif /* !DOC_HIDDEN */
diff --git a/src/pcm/pcm_local.h b/src/pcm/pcm_local.h index d52229d..d5726eb 100644
--- a/src/pcm/pcm_local.h
+++ b/src/pcm/pcm_local.h
@@ -184,6 +184,7 @@ typedef struct {
int (*poll_descriptors)(snd_pcm_t *pcm, struct pollfd *pfds, unsigned int space); /* locked */
int (*poll_revents)(snd_pcm_t *pcm, struct pollfd *pfds, unsigned int nfds, unsigned short *revents); /* locked */
int (*may_wait_for_avail_min)(snd_pcm_t *pcm, snd_pcm_uframes_t avail);
+ int (*mmap_begin)(snd_pcm_t *pcm, const snd_pcm_channel_area_t
+**areas, snd_pcm_uframes_t *offset, snd_pcm_uframes_t *frames); /*
+locked */
} snd_pcm_fast_ops_t;
struct _snd_pcm {
diff --git a/src/pcm/pcm_meter.c b/src/pcm/pcm_meter.c index 20b4187..28bb578 100644
--- a/src/pcm/pcm_meter.c
+++ b/src/pcm/pcm_meter.c
@@ -548,6 +548,7 @@ static const snd_pcm_fast_ops_t snd_pcm_meter_fast_ops = {
.poll_descriptors = snd_pcm_generic_poll_descriptors,
.poll_revents = snd_pcm_generic_poll_revents,
.may_wait_for_avail_min = snd_pcm_generic_may_wait_for_avail_min,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_mmap_emul.c b/src/pcm/pcm_mmap_emul.c index 009cebb..6fa5fe6 100644
--- a/src/pcm/pcm_mmap_emul.c
+++ b/src/pcm/pcm_mmap_emul.c
@@ -401,6 +401,7 @@ static const snd_pcm_fast_ops_t snd_pcm_mmap_emul_fast_ops = {
.poll_descriptors_count = snd_pcm_generic_poll_descriptors_count,
.poll_revents = snd_pcm_generic_poll_revents,
.may_wait_for_avail_min = snd_pcm_generic_may_wait_for_avail_min,
+ .mmap_begin = NULL,
};
#ifndef DOC_HIDDEN
diff --git a/src/pcm/pcm_multi.c b/src/pcm/pcm_multi.c index 53c414d..069d224 100644
--- a/src/pcm/pcm_multi.c
+++ b/src/pcm/pcm_multi.c
@@ -1042,6 +1042,7 @@ static const snd_pcm_fast_ops_t snd_pcm_multi_fast_ops = {
.poll_descriptors = snd_pcm_multi_poll_descriptors,
.poll_revents = snd_pcm_multi_poll_revents,
.may_wait_for_avail_min = snd_pcm_multi_may_wait_for_avail_min,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_null.c b/src/pcm/pcm_null.c index 1d81548..e6fa049 100644
--- a/src/pcm/pcm_null.c
+++ b/src/pcm/pcm_null.c
@@ -361,6 +361,7 @@ static const snd_pcm_fast_ops_t snd_pcm_null_fast_ops = {
.avail_update = snd_pcm_null_avail_update,
.mmap_commit = snd_pcm_null_mmap_commit,
.htimestamp = snd_pcm_generic_real_htimestamp,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_plugin.c b/src/pcm/pcm_plugin.c index ea60eb9..0714d2c 100644
--- a/src/pcm/pcm_plugin.c
+++ b/src/pcm/pcm_plugin.c
@@ -646,6 +646,7 @@ const snd_pcm_fast_ops_t snd_pcm_plugin_fast_ops = {
.poll_descriptors = snd_pcm_generic_poll_descriptors,
.poll_revents = snd_pcm_generic_poll_revents,
.may_wait_for_avail_min = snd_pcm_plugin_may_wait_for_avail_min,
+ .mmap_begin = NULL,
};
#endif
diff --git a/src/pcm/pcm_rate.c b/src/pcm/pcm_rate.c index 5dc8a92..f29739b 100644
--- a/src/pcm/pcm_rate.c
+++ b/src/pcm/pcm_rate.c
@@ -1217,6 +1217,7 @@ static const snd_pcm_fast_ops_t snd_pcm_rate_fast_ops = {
.poll_descriptors = snd_pcm_generic_poll_descriptors,
.poll_revents = snd_pcm_rate_poll_revents,
.may_wait_for_avail_min = snd_pcm_plugin_may_wait_for_avail_min,
+ .mmap_begin = NULL,
};
static const snd_pcm_ops_t snd_pcm_rate_ops = { diff --git a/src/pcm/pcm_share.c b/src/pcm/pcm_share.c index 5a540c4..b803a82 100644
--- a/src/pcm/pcm_share.c
+++ b/src/pcm/pcm_share.c
@@ -1346,6 +1346,7 @@ static const snd_pcm_fast_ops_t snd_pcm_share_fast_ops = {
.avail_update = snd_pcm_share_avail_update,
.htimestamp = snd_pcm_share_htimestamp,
.mmap_commit = snd_pcm_share_mmap_commit,
+ .mmap_begin = NULL,
};
/**
diff --git a/src/pcm/pcm_shm.c b/src/pcm/pcm_shm.c index 26a27a5..a18720f 100644
--- a/src/pcm/pcm_shm.c
+++ b/src/pcm/pcm_shm.c
@@ -629,6 +629,7 @@ static const snd_pcm_fast_ops_t snd_pcm_shm_fast_ops = {
.avail_update = snd_pcm_shm_avail_update,
.mmap_commit = snd_pcm_shm_mmap_commit,
.htimestamp = snd_pcm_shm_htimestamp,
+ .mmap_begin = NULL,
};
static int make_local_socket(const char *filename)
--
2.7.4
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