aio: implement io_pgetevents

This is the io_getevents equivalent of ppoll/pselect and allows to properly mix signals and aio completions (especially with IOCB_CMD_POLL) and atomically executes the following sequence: sigset_t origmask; pthread_sigmask(SIG_SETMASK, &sigmask, &origmask); ret = io_getevents(ctx, min_nr, nr, events, timeout); pthread_sigmask(SIG_SETMASK, &origmask, NULL); Note that unlike many other signal related calls we do not pass a sigmask size, as that would get us to 7 arguments, which aren't easily supported by the syscall infrastructure. It seems a lot less painful to just add a new syscall variant in the unlikely case we're going to increase the sigset size.

Christoph Hellwig committed 8 years ago

Commit 7a074e91 parent a3c0d438 files · +130 −11Browse files

Showing the changes to include/uapi/linux (1 of 8 files). Show all

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include/uapi/linux/aio_abi.h+6−0

@@ -29,6 +29,7 @@ · 28 unmodified lines
29	29
30	30	#include <linux/types.h>
31	31	#include <linux/fs.h>
	32	+#include <linux/signal.h>
32	33	#include <asm/byteorder.h>
33	34
34	35	typedef __kernel_ulong_t aio_context_t;
@@ -108,5 +109,10 @@ struct iocb { · 73 unmodified lines
108	109	#undef IFBIG
109	110	#undef IFLITTLE
110	111
	112	+struct __aio_sigset {
	113	+ sigset_t __user *sigmask;
	114	+ size_t sigsetsize;
	115	+};
	116	+
111	117	#endif /* __LINUX__AIO_ABI_H */
112	118