diff options
| -rw-r--r-- | arch/um/include/aio.h | 28 | ||||
| -rw-r--r-- | arch/um/include/init.h | 10 | ||||
| -rw-r--r-- | arch/um/include/irq_kern.h | 3 | ||||
| -rw-r--r-- | arch/um/kernel/irq.c | 41 | ||||
| -rw-r--r-- | arch/um/os-Linux/Makefile | 10 | ||||
| -rw-r--r-- | arch/um/os-Linux/aio.c | 398 |
6 files changed, 475 insertions, 15 deletions
diff --git a/arch/um/include/aio.h b/arch/um/include/aio.h new file mode 100644 index 0000000..423bae91 --- /dev/null +++ b/arch/um/include/aio.h @@ -0,0 +1,28 @@ +/* + * Copyright (C) 2004 Jeff Dike (jdike@karaya.com) + * Licensed under the GPL + */ + +#ifndef AIO_H__ +#define AIO_H__ + +enum aio_type { AIO_READ, AIO_WRITE, AIO_MMAP }; + +struct aio_thread_reply { + void *data; + int err; +}; + +struct aio_context { + int reply_fd; + struct aio_context *next; +}; + +#define INIT_AIO_CONTEXT { .reply_fd = -1, \ + .next = NULL } + +extern int submit_aio(enum aio_type type, int fd, char *buf, int len, + unsigned long long offset, int reply_fd, + struct aio_context *aio); + +#endif diff --git a/arch/um/include/init.h b/arch/um/include/init.h index 55c2693..cbd79a8 100644 --- a/arch/um/include/init.h +++ b/arch/um/include/init.h @@ -111,7 +111,15 @@ extern struct uml_param __uml_setup_start, __uml_setup_end; #ifndef __KERNEL__ -#define __initcall(fn) static initcall_t __initcall_##fn __init_call = fn +#define __define_initcall(level,fn) \ + static initcall_t __initcall_##fn __attribute_used__ \ + __attribute__((__section__(".initcall" level ".init"))) = fn + +/* Userspace initcalls shouldn't depend on anything in the kernel, so we'll + * make them run first. + */ +#define __initcall(fn) __define_initcall("1", fn) + #define __exitcall(fn) static exitcall_t __exitcall_##fn __exit_call = fn #define __init_call __attribute__ ((unused,__section__ (".initcall.init"))) diff --git a/arch/um/include/irq_kern.h b/arch/um/include/irq_kern.h index 3af52a6..c222d56 100644 --- a/arch/um/include/irq_kern.h +++ b/arch/um/include/irq_kern.h @@ -7,12 +7,15 @@ #define __IRQ_KERN_H__ #include "linux/interrupt.h" +#include "asm/ptrace.h" extern int um_request_irq(unsigned int irq, int fd, int type, irqreturn_t (*handler)(int, void *, struct pt_regs *), unsigned long irqflags, const char * devname, void *dev_id); +extern int init_aio_irq(int irq, char *name, + irqreturn_t (*handler)(int, void *, struct pt_regs *)); #endif diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c index 9f18061..dcd8149 100644 --- a/arch/um/kernel/irq.c +++ b/arch/um/kernel/irq.c @@ -31,7 +31,7 @@ #include "kern_util.h" #include "irq_user.h" #include "irq_kern.h" - +#include "os.h" /* * Generic, controller-independent functions: @@ -168,13 +168,32 @@ void __init init_IRQ(void) } } -/* - * Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */ +int init_aio_irq(int irq, char *name, irqreturn_t (*handler)(int, void *, + struct pt_regs *)) +{ + int fds[2], err; + + err = os_pipe(fds, 1, 1); + if(err){ + printk("init_aio_irq - os_pipe failed, err = %d\n", -err); + goto out; + } + + err = um_request_irq(irq, fds[0], IRQ_READ, handler, + SA_INTERRUPT | SA_SAMPLE_RANDOM, name, + (void *) (long) fds[0]); + if(err){ + printk("init_aio_irq - : um_request_irq failed, err = %d\n", + err); + goto out_close; + } + + err = fds[1]; + goto out; + + out_close: + os_close_file(fds[0]); + os_close_file(fds[1]); + out: + return(err); +} diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile index 4ddf540..351d969 100644 --- a/arch/um/os-Linux/Makefile +++ b/arch/um/os-Linux/Makefile @@ -3,11 +3,15 @@ # Licensed under the GPL # -obj-y = elf_aux.o file.o process.o signal.o time.o tty.o user_syms.o drivers/ \ - sys-$(SUBARCH)/ +obj-y = aio.o elf_aux.o file.o process.o signal.o time.o tty.o user_syms.o \ + drivers/ sys-$(SUBARCH)/ -USER_OBJS := elf_aux.o file.o process.o signal.o time.o tty.o +USER_OBJS := aio.o elf_aux.o file.o process.o signal.o time.o tty.o CFLAGS_user_syms.o += -DSUBARCH_$(SUBARCH) +HAVE_AIO_ABI := $(shell [ -r /usr/include/linux/aio_abi.h ] && \ + echo -DHAVE_AIO_ABI ) +CFLAGS_aio.o += $(HAVE_AIO_ABI) + include arch/um/scripts/Makefile.rules diff --git a/arch/um/os-Linux/aio.c b/arch/um/os-Linux/aio.c new file mode 100644 index 0000000..f2ca299 --- /dev/null +++ b/arch/um/os-Linux/aio.c @@ -0,0 +1,398 @@ +/* + * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com) + * Licensed under the GPL + */ + +#include <stdlib.h> +#include <unistd.h> +#include <signal.h> +#include <errno.h> +#include <sched.h> +#include <sys/syscall.h> +#include "os.h" +#include "helper.h" +#include "aio.h" +#include "init.h" +#include "user.h" +#include "mode.h" + +struct aio_thread_req { + enum aio_type type; + int io_fd; + unsigned long long offset; + char *buf; + int len; + struct aio_context *aio; +}; + +static int aio_req_fd_r = -1; +static int aio_req_fd_w = -1; + +#if defined(HAVE_AIO_ABI) +#include <linux/aio_abi.h> + +/* If we have the headers, we are going to build with AIO enabled. + * If we don't have aio in libc, we define the necessary stubs here. + */ + +#if !defined(HAVE_AIO_LIBC) + +static long io_setup(int n, aio_context_t *ctxp) +{ + return syscall(__NR_io_setup, n, ctxp); +} + +static long io_submit(aio_context_t ctx, long nr, struct iocb **iocbpp) +{ + return syscall(__NR_io_submit, ctx, nr, iocbpp); +} + +static long io_getevents(aio_context_t ctx_id, long min_nr, long nr, + struct io_event *events, struct timespec *timeout) +{ + return syscall(__NR_io_getevents, ctx_id, min_nr, nr, events, timeout); +} + +#endif + +/* The AIO_MMAP cases force the mmapped page into memory here + * rather than in whatever place first touches the data. I used + * to do this by touching the page, but that's delicate because + * gcc is prone to optimizing that away. So, what's done here + * is we read from the descriptor from which the page was + * mapped. The caller is required to pass an offset which is + * inside the page that was mapped. Thus, when the read + * returns, we know that the page is in the page cache, and + * that it now backs the mmapped area. + */ + +static int do_aio(aio_context_t ctx, enum aio_type type, int fd, char *buf, + int len, unsigned long long offset, struct aio_context *aio) +{ + struct iocb iocb, *iocbp = &iocb; + char c; + int err; + + iocb = ((struct iocb) { .aio_data = (unsigned long) aio, + .aio_reqprio = 0, + .aio_fildes = fd, + .aio_buf = (unsigned long) buf, + .aio_nbytes = len, + .aio_offset = offset, + .aio_reserved1 = 0, + .aio_reserved2 = 0, + .aio_reserved3 = 0 }); + + switch(type){ + case AIO_READ: + iocb.aio_lio_opcode = IOCB_CMD_PREAD; + err = io_submit(ctx, 1, &iocbp); + break; + case AIO_WRITE: + iocb.aio_lio_opcode = IOCB_CMD_PWRITE; + err = io_submit(ctx, 1, &iocbp); + break; + case AIO_MMAP: + iocb.aio_lio_opcode = IOCB_CMD_PREAD; + iocb.aio_buf = (unsigned long) &c; + iocb.aio_nbytes = sizeof(c); + err = io_submit(ctx, 1, &iocbp); + break; + default: + printk("Bogus op in do_aio - %d\n", type); + err = -EINVAL; + break; + } + if(err > 0) + err = 0; + + return err; +} + +static aio_context_t ctx = 0; + +static int aio_thread(void *arg) +{ + struct aio_thread_reply reply; + struct io_event event; + int err, n, reply_fd; + + signal(SIGWINCH, SIG_IGN); + + while(1){ + n = io_getevents(ctx, 1, 1, &event, NULL); + if(n < 0){ + if(errno == EINTR) + continue; + printk("aio_thread - io_getevents failed, " + "errno = %d\n", errno); + } + else { + reply = ((struct aio_thread_reply) + { .data = (void *) (long) event.data, + .err = event.res }); + reply_fd = ((struct aio_context *) reply.data)->reply_fd; + err = os_write_file(reply_fd, &reply, sizeof(reply)); + if(err != sizeof(reply)) + printk("not_aio_thread - write failed, " + "fd = %d, err = %d\n", + aio_req_fd_r, -err); + } + } + return 0; +} + +#endif + +static int do_not_aio(struct aio_thread_req *req) +{ + char c; + int err; + + switch(req->type){ + case AIO_READ: + err = os_seek_file(req->io_fd, req->offset); + if(err) + goto out; + + err = os_read_file(req->io_fd, req->buf, req->len); + break; + case AIO_WRITE: + err = os_seek_file(req->io_fd, req->offset); + if(err) + goto out; + + err = os_write_file(req->io_fd, req->buf, req->len); + break; + case AIO_MMAP: + err = os_seek_file(req->io_fd, req->offset); + if(err) + goto out; + + err = os_read_file(req->io_fd, &c, sizeof(c)); + break; + default: + printk("do_not_aio - bad request type : %d\n", req->type); + err = -EINVAL; + break; + } + + out: + return err; +} + +static int not_aio_thread(void *arg) +{ + struct aio_thread_req req; + struct aio_thread_reply reply; + int err; + + signal(SIGWINCH, SIG_IGN); + while(1){ + err = os_read_file(aio_req_fd_r, &req, sizeof(req)); + if(err != sizeof(req)){ + if(err < 0) + printk("not_aio_thread - read failed, " + "fd = %d, err = %d\n", aio_req_fd_r, + -err); + else { + printk("not_aio_thread - short read, fd = %d, " + "length = %d\n", aio_req_fd_r, err); + } + continue; + } + err = do_not_aio(&req); + reply = ((struct aio_thread_reply) { .data = req.aio, + .err = err }); + err = os_write_file(req.aio->reply_fd, &reply, sizeof(reply)); + if(err != sizeof(reply)) + printk("not_aio_thread - write failed, fd = %d, " + "err = %d\n", aio_req_fd_r, -err); + } +} + +static int aio_pid = -1; + +static int init_aio_24(void) +{ + unsigned long stack; + int fds[2], err; + + err = os_pipe(fds, 1, 1); + if(err) + goto out; + + aio_req_fd_w = fds[0]; + aio_req_fd_r = fds[1]; + err = run_helper_thread(not_aio_thread, NULL, + CLONE_FILES | CLONE_VM | SIGCHLD, &stack, 0); + if(err < 0) + goto out_close_pipe; + + aio_pid = err; + goto out; + + out_close_pipe: + os_close_file(fds[0]); + os_close_file(fds[1]); + aio_req_fd_w = -1; + aio_req_fd_r = -1; + out: +#ifndef HAVE_AIO_ABI + printk("/usr/include/linux/aio_abi.h not present during build\n"); +#endif + printk("2.6 host AIO support not used - falling back to I/O " + "thread\n"); + return 0; +} + +#ifdef HAVE_AIO_ABI +#define DEFAULT_24_AIO 0 +static int init_aio_26(void) +{ + unsigned long stack; + int err; + + if(io_setup(256, &ctx)){ + printk("aio_thread failed to initialize context, err = %d\n", + errno); + return -errno; + } + + err = run_helper_thread(aio_thread, NULL, + CLONE_FILES | CLONE_VM | SIGCHLD, &stack, 0); + if(err < 0) + return -errno; + + aio_pid = err; + + printk("Using 2.6 host AIO\n"); + return 0; +} + +static int submit_aio_26(enum aio_type type, int io_fd, char *buf, int len, + unsigned long long offset, struct aio_context *aio) +{ + struct aio_thread_reply reply; + int err; + + err = do_aio(ctx, type, io_fd, buf, len, offset, aio); + if(err){ + reply = ((struct aio_thread_reply) { .data = aio, + .err = err }); + err = os_write_file(aio->reply_fd, &reply, sizeof(reply)); + if(err != sizeof(reply)) + printk("submit_aio_26 - write failed, " + "fd = %d, err = %d\n", aio->reply_fd, -err); + else err = 0; + } + + return err; +} + +#else +#define DEFAULT_24_AIO 1 +static int init_aio_26(void) +{ + return -ENOSYS; +} + +static int submit_aio_26(enum aio_type type, int io_fd, char *buf, int len, + unsigned long long offset, struct aio_context *aio) +{ + return -ENOSYS; +} +#endif + +static int aio_24 = DEFAULT_24_AIO; + +static int __init set_aio_24(char *name, int *add) +{ + aio_24 = 1; + return 0; +} + +__uml_setup("aio=2.4", set_aio_24, +"aio=2.4\n" +" This is used to force UML to use 2.4-style AIO even when 2.6 AIO is\n" +" available. 2.4 AIO is a single thread that handles one request at a\n" +" time, synchronously. 2.6 AIO is a thread which uses the 2.6 AIO \n" +" interface to handle an arbitrary number of pending requests. 2.6 AIO \n" +" is not available in tt mode, on 2.4 hosts, or when UML is built with\n" +" /usr/include/linux/aio_abi.h not available. Many distributions don't\n" +" include aio_abi.h, so you will need to copy it from a kernel tree to\n" +" your /usr/include/linux in order to build an AIO-capable UML\n\n" +); + +static int init_aio(void) +{ + int err; + + CHOOSE_MODE(({ + if(!aio_24){ + printk("Disabling 2.6 AIO in tt mode\n"); + aio_24 = 1; + } }), (void) 0); + + if(!aio_24){ + err = init_aio_26(); + if(err && (errno == ENOSYS)){ + printk("2.6 AIO not supported on the host - " + "reverting to 2.4 AIO\n"); + aio_24 = 1; + } + else return err; + } + + if(aio_24) + return init_aio_24(); + + return 0; +} + +/* The reason for the __initcall/__uml_exitcall asymmetry is that init_aio + * needs to be called when the kernel is running because it calls run_helper, + * which needs get_free_page. exit_aio is a __uml_exitcall because the generic + * kernel does not run __exitcalls on shutdown, and can't because many of them + * break when called outside of module unloading. + */ +__initcall(init_aio); + +static void exit_aio(void) +{ + if(aio_pid != -1) + os_kill_process(aio_pid, 1); +} + +__uml_exitcall(exit_aio); + +static int submit_aio_24(enum aio_type type, int io_fd, char *buf, int len, + unsigned long long offset, struct aio_context *aio) +{ + struct aio_thread_req req = { .type = type, + .io_fd = io_fd, + .offset = offset, + .buf = buf, + .len = len, + .aio = aio, + }; + int err; + + err = os_write_file(aio_req_fd_w, &req, sizeof(req)); + if(err == sizeof(req)) + err = 0; + + return err; +} + +int submit_aio(enum aio_type type, int io_fd, char *buf, int len, + unsigned long long offset, int reply_fd, + struct aio_context *aio) +{ + aio->reply_fd = reply_fd; + if(aio_24) + return submit_aio_24(type, io_fd, buf, len, offset, aio); + else { + return submit_aio_26(type, io_fd, buf, len, offset, aio); + } +} |
