mirrors/pipewire
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/pipewire/pipewire.git synced 2025-11-05 13:30:02 -05:00
Code Issues Projects Releases Packages Wiki Activity Actions

mem: add support for ringbuffers

Browse source 
Add an option to map the memory twice in contigious memory to
make it easier to deal with ringbuffers.
This commit is contained in:
Wim Taymans 2017-04-26 10:56:00 +02:00
parent edb21a0ff8
commit ed273ec465
3 changed files with 87 additions and 35 deletions
Download patch file Download diff file Expand all files Collapse all files

74
pinos/client/mem.c
View file

@ -75,18 +75,66 @@ static inline int memfd_create(const char *name, unsigned int flags) {
#undef USE_MEMFD
SpaResult
pinos_memblock_map (PinosMemblock *mem)
{
if (mem->ptr != NULL)
return SPA_RESULT_OK;
if (mem->flags & PINOS_MEMBLOCK_FLAG_MAP_READWRITE) {
int prot = 0;
if (mem->flags & PINOS_MEMBLOCK_FLAG_MAP_READ)
prot |= PROT_READ;
if (mem->flags & PINOS_MEMBLOCK_FLAG_MAP_WRITE)
prot |= PROT_WRITE;
if (mem->flags & PINOS_MEMBLOCK_FLAG_MAP_TWICE) {
void *ptr;
mem->ptr = mmap (NULL, mem->size << 1, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (mem->ptr == MAP_FAILED)
return SPA_RESULT_NO_MEMORY;
ptr = mmap (mem->ptr, mem->size, prot, MAP_FIXED | MAP_SHARED, mem->fd, mem->offset);
if (ptr != mem->ptr) {
munmap (mem->ptr, mem->size << 1);
return SPA_RESULT_NO_MEMORY;
}
ptr = mmap (mem->ptr + mem->size, mem->size, prot, MAP_FIXED | MAP_SHARED, mem->fd, mem->offset);
if (ptr != mem->ptr + mem->size) {
munmap (mem->ptr, mem->size << 1);
return SPA_RESULT_NO_MEMORY;
}
} else {
mem->ptr = mmap (NULL, mem->size, prot, MAP_SHARED, mem->fd, 0);
if (mem->ptr == MAP_FAILED)
return SPA_RESULT_NO_MEMORY;
}
} else {
mem->ptr = NULL;
}
return SPA_RESULT_OK;
}
SpaResult
pinos_memblock_alloc (PinosMemblockFlags flags,
size_t size,
PinosMemblock *mem)
{
bool use_fd;
if (mem == NULL || size == 0)
return SPA_RESULT_INVALID_ARGUMENTS;
mem->offset = 0;
mem->flags = flags;
mem->size = size;
if (flags & PINOS_MEMBLOCK_FLAG_WITH_FD) {
use_fd = !!(flags & (PINOS_MEMBLOCK_FLAG_MAP_TWICE | PINOS_MEMBLOCK_FLAG_WITH_FD));
if (use_fd) {
#ifdef USE_MEMFD
mem->fd = memfd_create ("pinos-memfd", MFD_CLOEXEC | MFD_ALLOW_SEALING);
if (mem->fd == -1) {
@ -116,27 +164,23 @@ pinos_memblock_alloc (PinosMemblockFlags flags,
}
}
#endif
if (flags & PINOS_MEMBLOCK_FLAG_MAP_READWRITE) {
int prot = 0;
if (flags & PINOS_MEMBLOCK_FLAG_MAP_READ)
prot |= PROT_READ;
if (flags & PINOS_MEMBLOCK_FLAG_MAP_WRITE)
prot |= PROT_WRITE;
mem->ptr = mmap (NULL, size, prot, MAP_SHARED, mem->fd, 0);
if (mem->ptr == MAP_FAILED)
return SPA_RESULT_NO_MEMORY;
} else {
mem->ptr = NULL;
}
if (pinos_memblock_map (mem) != SPA_RESULT_OK)
goto mmap_failed;
} else {
mem->ptr = malloc (size);
if (mem->ptr == NULL)
return SPA_RESULT_NO_MEMORY;
mem->fd = -1;
}
if (!(flags & PINOS_MEMBLOCK_FLAG_WITH_FD) && mem->fd != -1) {
close (mem->fd);
mem->fd = -1;
}
return SPA_RESULT_OK;
mmap_failed:
close (mem->fd);
return SPA_RESULT_NO_MEMORY;
}
void