From: Jens Axboe <jens.axboe@oracle.com>
Date: Fri, 3 Jul 2009 20:52:38 +0000 (+0200)
Subject: mmap engine: allow full mmaps for 64-bit machines
X-Git-Tag: fio-1.31~11
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=ed47cbf7063df84343cd79fdc64eb7bbf7d6df2a;p=fio.git

mmap engine: allow full mmaps for 64-bit machines

No need to do partial mmaps there.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---

diff --git a/engines/mmap.c b/engines/mmap.c
index bd9a9428..71abfb9a 100644
--- a/engines/mmap.c
+++ b/engines/mmap.c
@@ -26,7 +26,6 @@ static int fio_mmap_file(struct thread_data *td, struct fio_file *f,
 			 size_t length, off_t off)
 {
 	int flags = 0;
-	int ret = 0;
 
 	if (td_rw(td))
 		flags = PROT_READ | PROT_WRITE;
@@ -40,10 +39,8 @@ static int fio_mmap_file(struct thread_data *td, struct fio_file *f,
 
 	f->mmap_ptr = mmap(NULL, length, flags, MAP_SHARED, f->fd, off);
 	if (f->mmap_ptr == MAP_FAILED) {
-		int err = errno;
-
 		f->mmap_ptr = NULL;
-		td_verror(td, err, "mmap");
+		td_verror(td, errno, "mmap");
 		goto err;
 	}
 
@@ -60,29 +57,27 @@ static int fio_mmap_file(struct thread_data *td, struct fio_file *f,
 	}
 
 err:
-	return ret;
+	if (td->error && f->mmap_ptr)
+		munmap(f->mmap_ptr, length);
+		
+	return td->error;
 }
 
-static int fio_mmapio_prep(struct thread_data *td, struct io_u *io_u)
+/*
+ * Just mmap an appropriate portion, we cannot mmap the full extent
+ */
+static int fio_mmapio_prep_limited(struct thread_data *td, struct io_u *io_u)
 {
 	struct fio_file *f = io_u->file;
-	int ret = 0;
 
 	if (io_u->buflen > mmap_map_size) {
 		log_err("fio: bs too big for mmap engine\n");
-		ret = EIO;
-		goto err;
+		return EIO;
 	}
 
-	if (io_u->offset >= f->mmap_off &&
-	    io_u->offset + io_u->buflen < f->mmap_off + f->mmap_sz)
-		goto done;
-
 	if (f->mmap_ptr) {
-		if (munmap(f->mmap_ptr, f->mmap_sz) < 0) {
-			ret = errno;
-			goto err;
-		}
+		if (munmap(f->mmap_ptr, f->mmap_sz) < 0)
+			return errno;
 		f->mmap_ptr = NULL;
 	}
 
@@ -92,15 +87,58 @@ static int fio_mmapio_prep(struct thread_data *td, struct io_u *io_u)
 
 	f->mmap_off = io_u->offset;
 
+	return fio_mmap_file(td, f, f->mmap_sz, f->mmap_off);
+}
+
+/*
+ * Attempt to mmap the entire file
+ */
+static int fio_mmapio_prep_full(struct thread_data *td, struct io_u *io_u)
+{
+	struct fio_file *f = io_u->file;
+	int ret;
+
+	if (fio_file_partial_mmap(f))
+		return EINVAL;
+
+	if (f->mmap_ptr) {
+		if (munmap(f->mmap_ptr, f->mmap_sz) < 0)
+			return errno;
+		f->mmap_ptr = NULL;
+	}
+
+	f->mmap_sz = f->io_size;
+	f->mmap_off = 0;
+
 	ret = fio_mmap_file(td, f, f->mmap_sz, f->mmap_off);
-done:
-	if (!ret)
-		io_u->mmap_data = f->mmap_ptr + io_u->offset - f->mmap_off -
-					f->file_offset;
-err:
+	if (ret)
+		fio_file_set_partial_mmap(f);
+
 	return ret;
 }
 
+static int fio_mmapio_prep(struct thread_data *td, struct io_u *io_u)
+{
+	struct fio_file *f = io_u->file;
+	int ret;
+
+	if (io_u->offset >= f->mmap_off &&
+	    io_u->offset + io_u->buflen < f->mmap_off + f->mmap_sz)
+		goto done;
+
+	if (fio_mmapio_prep_full(td, io_u)) {
+		td_clear_error(td);
+		ret = fio_mmapio_prep_limited(td, io_u);
+		if (ret)
+			return ret;
+	}
+
+done:
+	io_u->mmap_data = f->mmap_ptr + io_u->offset - f->mmap_off -
+				f->file_offset;
+	return 0;
+}
+
 static int fio_mmapio_queue(struct thread_data *td, struct io_u *io_u)
 {
 	struct fio_file *f = io_u->file;
diff --git a/file.h b/file.h
index 7024d5ee..6aa5b502 100644
--- a/file.h
+++ b/file.h
@@ -20,6 +20,7 @@ enum fio_file_flags {
 	FIO_FILE_done		= 1 << 3,	/* io completed to this file */
 	FIO_FILE_size_known	= 1 << 4,	/* size has been set */
 	FIO_FILE_hashed		= 1 << 5,	/* file is on hash */
+	FIO_FILE_partial_mmap	= 1 << 6,	/* can't do full mmap */
 };
 
 enum file_lock_mode {
@@ -114,6 +115,7 @@ FILE_FLAG_FNS(extend);
 FILE_FLAG_FNS(done);
 FILE_FLAG_FNS(size_known);
 FILE_FLAG_FNS(hashed);
+FILE_FLAG_FNS(partial_mmap);
 #undef FILE_FLAG_FNS
 
 /*