From 91acb21f084aa244f26839406ae7ed8aa3668058 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Mon, 10 Oct 2005 23:10:32 -0400 Subject: [PATCH] uml: revert block driver use of host AIO The patch to use host AIO support that I submitted early after 2.6.13 exposed some problems in the block driver. I have fixes for these, but am not comfortable putting them into 2.6.14 at this late date. So, this patch reverts the use of host AIO. I will resubmit the original patch, plus fixes to the driver after 2.6.14 in order to get a reasonable amount of testing before they're exposed to the general public. Signed-off-by: Jeff Dike Signed-off-by: Linus Torvalds --- arch/um/os-Linux/aio.c | 205 +++++++++++++++++++++++-------------------------- 1 file changed, 94 insertions(+), 111 deletions(-) (limited to 'arch/um/os-Linux/aio.c') diff --git a/arch/um/os-Linux/aio.c b/arch/um/os-Linux/aio.c index f6e64026f99..41cfb094420 100644 --- a/arch/um/os-Linux/aio.c +++ b/arch/um/os-Linux/aio.c @@ -6,7 +6,6 @@ #include #include #include -#include #include #include #include @@ -17,31 +16,18 @@ #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; -static int update_aio(struct aio_context *aio, int res) -{ - if(res < 0) - aio->len = res; - else if((res == 0) && (aio->type == AIO_READ)){ - /* This is the EOF case - we have hit the end of the file - * and it ends in a partial block, so we fill the end of - * the block with zeros and claim success. - */ - memset(aio->data, 0, aio->len); - aio->len = 0; - } - else if(res > 0){ - aio->len -= res; - aio->data += res; - aio->offset += res; - return aio->len; - } - - return 0; -} - #if defined(HAVE_AIO_ABI) #include @@ -80,7 +66,8 @@ static long io_getevents(aio_context_t ctx_id, long min_nr, long nr, * that it now backs the mmapped area. */ -static int do_aio(aio_context_t ctx, struct aio_context *aio) +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; @@ -88,39 +75,40 @@ static int do_aio(aio_context_t ctx, struct aio_context *aio) iocb = ((struct iocb) { .aio_data = (unsigned long) aio, .aio_reqprio = 0, - .aio_fildes = aio->fd, - .aio_buf = (unsigned long) aio->data, - .aio_nbytes = aio->len, - .aio_offset = aio->offset, + .aio_fildes = fd, + .aio_buf = (unsigned long) buf, + .aio_nbytes = len, + .aio_offset = offset, .aio_reserved1 = 0, .aio_reserved2 = 0, .aio_reserved3 = 0 }); - switch(aio->type){ + 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", aio->type); + printk("Bogus op in do_aio - %d\n", type); err = -EINVAL; - goto out; + break; } - err = io_submit(ctx, 1, &iocbp); if(err > 0) err = 0; else err = -errno; - out: return err; } @@ -129,9 +117,8 @@ static aio_context_t ctx = 0; static int aio_thread(void *arg) { struct aio_thread_reply reply; - struct aio_context *aio; struct io_event event; - int err, n; + int err, n, reply_fd; signal(SIGWINCH, SIG_IGN); @@ -144,22 +131,14 @@ static int aio_thread(void *arg) "errno = %d\n", errno); } else { - /* This is safe as we've just a pointer here. */ - aio = (struct aio_context *) (long) event.data; - if(update_aio(aio, event.res)){ - do_aio(ctx, aio); - continue; - } - reply = ((struct aio_thread_reply) - { .data = aio, - .err = aio->len }); - err = os_write_file(aio->reply_fd, &reply, - sizeof(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("aio_thread - write failed, " - "fd = %d, err = %d\n", aio->reply_fd, - -err); + printk("aio_thread - write failed, fd = %d, " + "err = %d\n", aio_req_fd_r, -err); } } return 0; @@ -167,35 +146,35 @@ static int aio_thread(void *arg) #endif -static int do_not_aio(struct aio_context *aio) +static int do_not_aio(struct aio_thread_req *req) { char c; int err; - switch(aio->type){ + switch(req->type){ case AIO_READ: - err = os_seek_file(aio->fd, aio->offset); + err = os_seek_file(req->io_fd, req->offset); if(err) goto out; - err = os_read_file(aio->fd, aio->data, aio->len); + err = os_read_file(req->io_fd, req->buf, req->len); break; case AIO_WRITE: - err = os_seek_file(aio->fd, aio->offset); + err = os_seek_file(req->io_fd, req->offset); if(err) goto out; - err = os_write_file(aio->fd, aio->data, aio->len); + err = os_write_file(req->io_fd, req->buf, req->len); break; case AIO_MMAP: - err = os_seek_file(aio->fd, aio->offset); + err = os_seek_file(req->io_fd, req->offset); if(err) goto out; - err = os_read_file(aio->fd, &c, sizeof(c)); + err = os_read_file(req->io_fd, &c, sizeof(c)); break; default: - printk("do_not_aio - bad request type : %d\n", aio->type); + printk("do_not_aio - bad request type : %d\n", req->type); err = -EINVAL; break; } @@ -206,14 +185,14 @@ static int do_not_aio(struct aio_context *aio) static int not_aio_thread(void *arg) { - struct aio_context *aio; + 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, &aio, sizeof(aio)); - if(err != sizeof(aio)){ + 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, @@ -224,34 +203,17 @@ static int not_aio_thread(void *arg) } continue; } - again: - err = do_not_aio(aio); - - if(update_aio(aio, err)) - goto again; - - reply = ((struct aio_thread_reply) { .data = aio, - .err = aio->len }); - err = os_write_file(aio->reply_fd, &reply, sizeof(reply)); + 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 submit_aio_24(struct aio_context *aio) -{ - int err; - - err = os_write_file(aio_req_fd_w, &aio, sizeof(aio)); - if(err == sizeof(aio)) - err = 0; - - return err; -} - static int aio_pid = -1; -static int (*submit_proc)(struct aio_context *aio); static int init_aio_24(void) { @@ -283,33 +245,11 @@ static int init_aio_24(void) #endif printk("2.6 host AIO support not used - falling back to I/O " "thread\n"); - - submit_proc = submit_aio_24; - return 0; } #ifdef HAVE_AIO_ABI #define DEFAULT_24_AIO 0 -static int submit_aio_26(struct aio_context *aio) -{ - struct aio_thread_reply reply; - int err; - - err = do_aio(ctx, 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; -} - static int init_aio_26(void) { unsigned long stack; @@ -330,22 +270,39 @@ static int init_aio_26(void) 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; - submit_proc = submit_aio_26; + 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 0; + return err; } #else #define DEFAULT_24_AIO 1 -static int submit_aio_26(struct aio_context *aio) +static int init_aio_26(void) { return -ENOSYS; } -static int init_aio_26(void) +static int submit_aio_26(enum aio_type type, int io_fd, char *buf, int len, + unsigned long long offset, struct aio_context *aio) { - submit_proc = submit_aio_26; return -ENOSYS; } #endif @@ -412,7 +369,33 @@ static void exit_aio(void) __uml_exitcall(exit_aio); -int submit_aio(struct aio_context *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) { - return (*submit_proc)(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); + } } -- cgit v1.2.3