X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=engines%2Fsplice.c;h=a847f9caaf7d5ca35cf08d9cadca59a50345d5bc;hp=f54b4414ae1851318ae79fb5aa40d67ea8e5b9f3;hb=f3f552b9920cc45c5b1f9c679f36b8ddb13927d0;hpb=f24254e1d142e80dc76d1f2e316da12f6ec125ee

diff --git a/engines/splice.c b/engines/splice.c
index f54b4414..a847f9ca 100644
--- a/engines/splice.c
+++ b/engines/splice.c
@@ -11,6 +11,7 @@
 #include <errno.h>
 #include <assert.h>
 #include <sys/poll.h>
+#include <sys/mman.h>
 
 #include "../fio.h"
 
@@ -19,6 +20,7 @@
 struct spliceio_data {
 	int pipe[2];
 	int vmsplice_to_user;
+	int vmsplice_to_user_map;
 };
 
 /*
@@ -75,25 +77,44 @@ static int fio_splice_read(struct thread_data *td, struct io_u *io_u)
 	struct spliceio_data *sd = td->io_ops->data;
 	struct fio_file *f = io_u->file;
 	struct iovec iov;
-	int ret, buflen;
+	int ret , buflen, mmap_len;
 	off_t offset;
-	void *p;
+	void *p, *map;
 
+restart:
+	ret = 0;
 	offset = io_u->offset;
-	buflen = io_u->xfer_buflen;
-	p = io_u->xfer_buf;
+	mmap_len = buflen = io_u->xfer_buflen;
+
+	if (sd->vmsplice_to_user_map) {
+		map = mmap(io_u->xfer_buf, buflen, PROT_READ, MAP_PRIVATE|OS_MAP_ANON, 0, 0);
+		if (map == MAP_FAILED) {
+			td_verror(td, errno, "mmap io_u");
+			return -1;
+		}
+
+		p = map;
+	} else {
+		map = NULL;
+		p = io_u->xfer_buf;
+	}
+
 	while (buflen) {
 		int this_len = buflen;
+		int flags = 0;
 
-		if (this_len > SPLICE_DEF_SIZE)
+		if (this_len > SPLICE_DEF_SIZE) {
 			this_len = SPLICE_DEF_SIZE;
+			flags = SPLICE_F_MORE;
+		}
 
-		ret = splice(f->fd, &offset, sd->pipe[1], NULL, this_len, SPLICE_F_MORE);
+		ret = splice(f->fd, &offset, sd->pipe[1], NULL, this_len,flags);
 		if (ret < 0) {
 			if (errno == ENODATA || errno == EAGAIN)
 				continue;
 
-			return -errno;
+			td_verror(td, errno, "splice-from-fd");
+			break;
 		}
 
 		buflen -= ret;
@@ -103,20 +124,41 @@ static int fio_splice_read(struct thread_data *td, struct io_u *io_u)
 
 		while (iov.iov_len) {
 			ret = vmsplice(sd->pipe[0], &iov, 1, SPLICE_F_MOVE);
-			if (ret < 0)
-				return -errno;
-			else if (!ret)
-				return -ENODATA;
+			if (ret < 0) {
+				if (errno == EFAULT && sd->vmsplice_to_user_map) {
+					sd->vmsplice_to_user_map = 0;
+					munmap(map, mmap_len);
+					goto restart;
+				}
+				if (errno == EBADF) {
+					ret = -EBADF;
+					break;
+				}
+				td_verror(td, errno, "vmsplice");
+				break;
+			} else if (!ret) {
+				td_verror(td, ENODATA, "vmsplice");
+				ret = -1;
+				break;
+			}
 
 			iov.iov_len -= ret;
 			iov.iov_base += ret;
 		}
+		if (ret < 0)
+			break;
+	}
+
+	if (sd->vmsplice_to_user_map && munmap(map, mmap_len) < 0) {
+		td_verror(td, errno, "munnap io_u");
+		return -1;
 	}
+	if (ret < 0)
+		return ret;
 
 	return io_u->xfer_buflen;
 }
 
-
 /*
  * For splice writing, we can vmsplice our data buffer directly into a
  * pipe and then splice that to a file.
@@ -159,12 +201,22 @@ static int fio_splice_write(struct thread_data *td, struct io_u *io_u)
 static int fio_spliceio_queue(struct thread_data *td, struct io_u *io_u)
 {
 	struct spliceio_data *sd = td->io_ops->data;
-	int ret;
+	int uninitialized_var(ret);
+
+	fio_ro_check(td, io_u);
 
 	if (io_u->ddir == DDIR_READ) {
-		if (sd->vmsplice_to_user)
+		if (sd->vmsplice_to_user) {
 			ret = fio_splice_read(td, io_u);
-		else
+			/*
+			 * This kernel doesn't support vmsplice to user
+			 * space. Reset the vmsplice_to_user flag, so that
+			 * we retry below and don't hit this path again.
+			 */
+			if (ret == -EBADF)
+				sd->vmsplice_to_user = 0;
+		}
+		if (!sd->vmsplice_to_user)
 			ret = fio_splice_read_old(td, io_u);
 	} else if (io_u->ddir == DDIR_WRITE)
 		ret = fio_splice_write(td, io_u);
@@ -180,8 +232,12 @@ static int fio_spliceio_queue(struct thread_data *td, struct io_u *io_u)
 			io_u->error = errno;
 	}
 
-	if (io_u->error)
+	if (io_u->error) {
 		td_verror(td, io_u->error, "xfer");
+		if (io_u->error == EINVAL)
+			log_err("fio: looks like splice doesn't work on this"
+					" file system\n");
+	}
 
 	return FIO_Q_COMPLETED;
 }
@@ -194,7 +250,6 @@ static void fio_spliceio_cleanup(struct thread_data *td)
 		close(sd->pipe[0]);
 		close(sd->pipe[1]);
 		free(sd);
-		td->io_ops->data = NULL;
 	}
 }
 
@@ -209,9 +264,22 @@ static int fio_spliceio_init(struct thread_data *td)
 	}
 
 	/*
-	 * need some check for enabling this, for now just leave it disabled
+	 * Assume this work, we'll reset this if it doesn't
+	 */
+	sd->vmsplice_to_user = 1;
+
+	/*
+	 * Works with "real" vmsplice to user, eg mapping pages directly.
+	 * Reset if we fail.
+	 */
+	sd->vmsplice_to_user_map = 1;
+
+	/*
+	 * And if vmsplice_to_user works, we definitely need aligned
+	 * buffers. Just set ->odirect to force that.
 	 */
-	sd->vmsplice_to_user = 0;
+	if (td_read(td))
+		td->o.odirect = 1;
 
 	td->io_ops->data = sd;
 	return 0;