freebsd-nq/sys/modules/aio/Makefile

# $FreeBSD$

.PATH: ${.CURDIR}/../../kern

KMOD=	aio
SRCS=	vfs_aio.c opt_vfs_aio.h vnode_if.h

EXPORT_SYMS= aio_init_aioinfo aio_aqueue

.include <bsd.kmod.mk>
Make AIO a loadable module. Remove the explicit call to aio_proc_rundown() from exit1(), instead AIO will use at_exit(9). Add functions at_exec(9), rm_at_exec(9) which function nearly the same as at_exec(9) and rm_at_exec(9), these functions are called on behalf of modules at the time of execve(2) after the image activator has run. Use a modified version of tegge's suggestion via at_exec(9) to close an exploitable race in AIO. Fix SYSCALL_MODULE_HELPER such that it's archetecuterally neutral, the problem was that one had to pass it a paramater indicating the number of arguments which were actually the number of "int". Fix it by using an inline version of the AS macro against the syscall arguments. (AS should be available globally but we'll get to that later.) Add a primative system for dynamically adding kqueue ops, it's really not as sophisticated as it should be, but I'll discuss with jlemon when he's around. 2001-12-29 07:13:47 +00:00			`# $FreeBSD$`

			`.PATH: ${.CURDIR}/../../kern`

			`KMOD= aio`
			`SRCS= vfs_aio.c opt_vfs_aio.h vnode_if.h`

MFP4 (with some minor changes): Implement the linux_io_* syscalls (AIO). They are only enabled if the native AIO code is available (either compiled in to the kernel or as a module) at the time the functions are used. If the AIO stuff is not available there will be a ENOSYS. From the submitter: ---snip--- DESIGN NOTES: 1. Linux permits a process to own multiple AIO queues (distinguished by "context"), but FreeBSD creates only one single AIO queue per process. My code maintains a request queue (STAILQ of queue(3)) per "context", and throws all AIO requests of all contexts owned by a process into the single FreeBSD per-process AIO queue. When the process calls io_destroy(2), io_getevents(2), io_submit(2) and io_cancel(2), my code can pick out requests owned by the specified context from the single FreeBSD per-process AIO queue according to the per-context request queues maintained by my code. 2. The request queue maintained by my code stores contrast information between Linux IO control blocks (struct linux_iocb) and FreeBSD IO control blocks (struct aiocb). FreeBSD IO control block actually exists in userland memory space, required by FreeBSD native aio_XXXXXX(2). 3. It is quite troubling that the function io_getevents() of libaio-0.3.105 needs to use Linux-specific "struct aio_ring", which is a partial mirror of context in user space. I would rather take the address of context in kernel as the context ID, but the io_getevents() of libaio forces me to take the address of the "ring" in user space as the context ID. To my surprise, one comment line in the file "io_getevents.c" of libaio-0.3.105 reads: Ben will hate me for this REFERENCE: 1. Linux kernel source code: http://www.kernel.org/pub/linux/kernel/v2.6/ (include/linux/aio_abi.h, fs/aio.c) 2. Linux manual pages: http://www.kernel.org/pub/linux/docs/manpages/ (io_setup(2), io_destroy(2), io_getevents(2), io_submit(2), io_cancel(2)) 3. Linux Scalability Effort: http://lse.sourceforge.net/io/aio.html The design notes: http://lse.sourceforge.net/io/aionotes.txt 4. The package libaio, both source and binary: http://rpmfind.net/linux/rpm2html/search.php?query=libaio Simple transparent interface to Linux AIO system calls. 5. Libaio-oracle: http://oss.oracle.com/projects/libaio-oracle/ POSIX AIO implementation based on Linux AIO system calls (depending on libaio). ---snip--- Submitted by: Li, Xiao <intron@intron.ac> 2006-10-15 14:22:14 +00:00			`EXPORT_SYMS= aio_init_aioinfo aio_aqueue`

Make AIO a loadable module. Remove the explicit call to aio_proc_rundown() from exit1(), instead AIO will use at_exit(9). Add functions at_exec(9), rm_at_exec(9) which function nearly the same as at_exec(9) and rm_at_exec(9), these functions are called on behalf of modules at the time of execve(2) after the image activator has run. Use a modified version of tegge's suggestion via at_exec(9) to close an exploitable race in AIO. Fix SYSCALL_MODULE_HELPER such that it's archetecuterally neutral, the problem was that one had to pass it a paramater indicating the number of arguments which were actually the number of "int". Fix it by using an inline version of the AS macro against the syscall arguments. (AS should be available globally but we'll get to that later.) Add a primative system for dynamically adding kqueue ops, it's really not as sophisticated as it should be, but I'll discuss with jlemon when he's around. 2001-12-29 07:13:47 +00:00			`.include <bsd.kmod.mk>`