Merge branch 'post-2.6.15' of git://brick.kernel.dk/data/git/linux-2.6-block
[sfrench/cifs-2.6.git] / arch / um / os-Linux / aio.c
index f6e64026f9952b90d1af98625b152ef394c454e9..f897140cc4ae2ec6e76bb3610a510017f4679a7c 100644 (file)
@@ -6,42 +6,27 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <signal.h>
-#include <string.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;
 
-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 <linux/aio_abi.h>
 
@@ -53,18 +38,18 @@ static int update_aio(struct aio_context *aio, int res)
 
 static long io_setup(int n, aio_context_t *ctxp)
 {
-        return syscall(__NR_io_setup, n, 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);
+       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)
+                        struct io_event *events, struct timespec *timeout)
 {
-        return syscall(__NR_io_getevents, ctx_id, min_nr, nr, events, timeout);
+       return syscall(__NR_io_getevents, ctx_id, min_nr, nr, events, timeout);
 }
 
 #endif
@@ -80,226 +65,225 @@ 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;
-        int err;
-
-        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_reserved1 = 0,
-                                .aio_reserved2 = 0,
-                                .aio_reserved3 = 0 });
-
-        switch(aio->type){
-        case AIO_READ:
-                iocb.aio_lio_opcode = IOCB_CMD_PREAD;
-                break;
-        case AIO_WRITE:
-                iocb.aio_lio_opcode = IOCB_CMD_PWRITE;
-                break;
-        case AIO_MMAP:
-                iocb.aio_lio_opcode = IOCB_CMD_PREAD;
-                iocb.aio_buf = (unsigned long) &c;
-                iocb.aio_nbytes = sizeof(c);
-                break;
-        default:
-                printk("Bogus op in do_aio - %d\n", aio->type);
-                err = -EINVAL;
-                goto out;
-        }
-
-        err = io_submit(ctx, 1, &iocbp);
-        if(err > 0)
-                err = 0;
+       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;
        else
                err = -errno;
 
- out:
-        return err;
+       return err;
 }
 
 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;
-
-        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 {
-                       /* 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;
-                       }
+       struct aio_thread_reply reply;
+       struct io_event event;
+       int err, n, reply_fd;
 
-                        reply = ((struct aio_thread_reply)
-                               { .data = aio,
-                                 .err  = aio->len });
-                       err = os_write_file(aio->reply_fd, &reply,
-                                           sizeof(reply));
-                        if(err != sizeof(reply))
-                               printk("aio_thread - write failed, "
-                                      "fd = %d, err = %d\n", aio->reply_fd,
-                                      -err);
-                }
-        }
-        return 0;
+       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("aio_thread - write failed, fd = %d, "
+                                      "err = %d\n", aio_req_fd_r, -err);
+               }
+       }
+       return 0;
 }
 
 #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){
-        case AIO_READ:
-                err = os_seek_file(aio->fd, aio->offset);
-                if(err)
-                        goto out;
-
-                err = os_read_file(aio->fd, aio->data, aio->len);
-                break;
-        case AIO_WRITE:
-                err = os_seek_file(aio->fd, aio->offset);
-                if(err)
-                        goto out;
-
-                err = os_write_file(aio->fd, aio->data, aio->len);
-                break;
-        case AIO_MMAP:
-                err = os_seek_file(aio->fd, aio->offset);
-                if(err)
-                        goto out;
-
-                err = os_read_file(aio->fd, &c, sizeof(c));
-                break;
-        default:
-                printk("do_not_aio - bad request type : %d\n", aio->type);
-                err = -EINVAL;
-                break;
-        }
-
- out:
-        return err;
-}
+       char c;
+       int err;
 
-static int not_aio_thread(void *arg)
-{
-        struct aio_context *aio;
-        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)){
-                        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;
-                }
- 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));
-                if(err != sizeof(reply))
-                        printk("not_aio_thread - write failed, fd = %d, "
-                               "err = %d\n", aio_req_fd_r, -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 submit_aio_24(struct aio_context *aio)
+static int not_aio_thread(void *arg)
 {
-        int err;
+       struct aio_thread_req req;
+       struct aio_thread_reply reply;
+       int err;
 
-        err = os_write_file(aio_req_fd_w, &aio, sizeof(aio));
-        if(err == sizeof(aio))
-                err = 0;
+       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);
+       }
 
-        return err;
+       return 0;
 }
 
 static int aio_pid = -1;
-static int (*submit_proc)(struct aio_context *aio);
 
 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:
+       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");
-
-       submit_proc = submit_aio_24;
-
-        return 0;
+       return 0;
 }
 
 #ifdef HAVE_AIO_ABI
 #define DEFAULT_24_AIO 0
-static int submit_aio_26(struct aio_context *aio)
+static int init_aio_26(void)
+{
+       unsigned long stack;
+       int err;
+
+       if(io_setup(256, &ctx)){
+               err = -errno;
+               printk("aio_thread failed to initialize context, err = %d\n",
+                      errno);
+               return err;
+       }
+
+       err = run_helper_thread(aio_thread, NULL,
+                               CLONE_FILES | CLONE_VM | SIGCHLD, &stack, 0);
+       if(err < 0)
+               return err;
+
+       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, aio);
+       err = do_aio(ctx, type, io_fd, buf, len, offset, aio);
        if(err){
                reply = ((struct aio_thread_reply) { .data = aio,
-                                                    .err  = err });
+                                        .err  = err });
                err = os_write_file(aio->reply_fd, &reply, sizeof(reply));
                if(err != sizeof(reply))
                        printk("submit_aio_26 - write failed, "
@@ -310,43 +294,17 @@ static int submit_aio_26(struct aio_context *aio)
        return err;
 }
 
-static int init_aio_26(void)
-{
-        unsigned long stack;
-        int err;
-
-        if(io_setup(256, &ctx)){
-               err = -errno;
-                printk("aio_thread failed to initialize context, err = %d\n",
-                       errno);
-                return err;
-        }
-
-        err = run_helper_thread(aio_thread, NULL,
-                                CLONE_FILES | CLONE_VM | SIGCHLD, &stack, 0);
-        if(err < 0)
-                return err;
-
-        aio_pid = err;
-
-       printk("Using 2.6 host AIO\n");
-
-       submit_proc = submit_aio_26;
-
-        return 0;
-}
-
 #else
 #define DEFAULT_24_AIO 1
-static int submit_aio_26(struct aio_context *aio)
+static int init_aio_26(void)
 {
-        return -ENOSYS;
+       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;
+       return -ENOSYS;
 }
 #endif
 
@@ -354,8 +312,8 @@ static int aio_24 = DEFAULT_24_AIO;
 
 static int __init set_aio_24(char *name, int *add)
 {
-        aio_24 = 1;
-        return 0;
+       aio_24 = 1;
+       return 0;
 }
 
 __uml_setup("aio=2.4", set_aio_24,
@@ -372,28 +330,27 @@ __uml_setup("aio=2.4", set_aio_24,
 
 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;
+       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
@@ -406,13 +363,39 @@ __initcall(init_aio);
 
 static void exit_aio(void)
 {
-        if(aio_pid != -1)
-                os_kill_process(aio_pid, 1);
+       if(aio_pid != -1)
+               os_kill_process(aio_pid, 1);
 }
 
 __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);
+       }
 }