X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=engines%2Fmmap.c;h=05a4d5163ce5dbd45a3ba351419417e642b65be1;hp=d32fe969832009d871cb9956b0950ef6413d2a29;hb=ac89311241264280574c81e6400c9a0c59615082;hpb=36167d82e5f49dee91c6d2cd426068edee90e36f

diff --git a/engines/mmap.c b/engines/mmap.c
index d32fe969..05a4d516 100644
--- a/engines/mmap.c
+++ b/engines/mmap.c
@@ -1,52 +1,174 @@
 /*
- * regular read/write sync io engine
+ * mmap engine
+ *
+ * IO engine that reads/writes from files by doing memcpy to/from
+ * a memory mapped region of the file.
  *
  */
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <errno.h>
-#include <assert.h>
 #include <sys/mman.h>
 
 #include "../fio.h"
-#include "../os.h"
+
+/*
+ * Limits us to 2GB of mapped files in total
+ */
+#define MMAP_TOTAL_SZ	(2 * 1024 * 1024 * 1024UL)
+
+static unsigned long mmap_map_size;
+static unsigned long mmap_map_mask;
+
+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;
+	else if (td_write(td)) {
+		flags = PROT_WRITE;
+
+		if (td->o.verify != VERIFY_NONE)
+			flags |= PROT_READ;
+	} else
+		flags = PROT_READ;
+
+	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");
+		if (err == EINVAL && f->io_size > 2*1024*1024*1024UL)
+			log_err("fio: mmap size likely too large\n");
+		goto err;
+	}
+
+	if (file_invalidate_cache(td, f))
+		goto err;
+
+	if (!td_random(td)) {
+		if (madvise(f->mmap_ptr, length, MADV_SEQUENTIAL) < 0) {
+			td_verror(td, errno, "madvise");
+			goto err;
+		}
+	} else {
+		if (madvise(f->mmap_ptr, length, MADV_RANDOM) < 0) {
+			td_verror(td, errno, "madvise");
+			goto err;
+		}
+	}
+
+err:
+	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 = 0;
+
+	if (io_u->buflen > mmap_map_size) {
+		log_err("fio: bs too big for mmap engine\n");
+		ret = EIO;
+		goto err;
+	}
+
+	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;
+		}
+		f->mmap_ptr = NULL;
+	}
+
+	f->mmap_sz = mmap_map_size;
+	if (f->mmap_sz  > f->io_size)
+		f->mmap_sz = f->io_size;
+
+	f->mmap_off = io_u->offset & ~mmap_map_mask;
+	if (io_u->offset + io_u->buflen >= f->mmap_off + f->mmap_sz)
+		f->mmap_off -= io_u->buflen;
+
+	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:
+	return ret;
+}
 
 static int fio_mmapio_queue(struct thread_data *td, struct io_u *io_u)
 {
 	struct fio_file *f = io_u->file;
-	unsigned long long real_off = io_u->offset - f->file_offset;
+
+	fio_ro_check(td, io_u);
 
 	if (io_u->ddir == DDIR_READ)
-		memcpy(io_u->xfer_buf, f->mmap + real_off, io_u->xfer_buflen);
+		memcpy(io_u->xfer_buf, io_u->mmap_data, io_u->xfer_buflen);
 	else if (io_u->ddir == DDIR_WRITE)
-		memcpy(f->mmap + real_off, io_u->xfer_buf, io_u->xfer_buflen);
+		memcpy(io_u->mmap_data, io_u->xfer_buf, io_u->xfer_buflen);
 	else if (io_u->ddir == DDIR_SYNC) {
-		if (msync(f->mmap, f->file_size, MS_SYNC))
+		if (msync(f->mmap_ptr, f->mmap_sz, MS_SYNC)) {
 			io_u->error = errno;
+			td_verror(td, io_u->error, "msync");
+		}
 	}
 
 	/*
 	 * not really direct, but should drop the pages from the cache
 	 */
-	if (td->odirect && io_u->ddir != DDIR_SYNC) {
-		if (msync(f->mmap + real_off, io_u->xfer_buflen, MS_SYNC) < 0)
+	if (td->o.odirect && io_u->ddir != DDIR_SYNC) {
+		if (msync(io_u->mmap_data, io_u->xfer_buflen, MS_SYNC) < 0) {
 			io_u->error = errno;
-		if (madvise(f->mmap + real_off, io_u->xfer_buflen,  MADV_DONTNEED) < 0)
+			td_verror(td, io_u->error, "msync");
+		}
+		if (madvise(io_u->mmap_data, io_u->xfer_buflen,  MADV_DONTNEED) < 0) {
 			io_u->error = errno;
+			td_verror(td, io_u->error, "madvise");
+		}
 	}
 
-	if (io_u->error)
-		td_verror(td, io_u->error);
-
 	return FIO_Q_COMPLETED;
 }
 
+static int fio_mmapio_init(struct thread_data *td)
+{
+	unsigned long shift, mask;
+
+	mmap_map_size = MMAP_TOTAL_SZ / td->o.nr_files;
+	mask = mmap_map_size;
+	shift = 0;
+	do {
+		mask >>= 1;
+		if (!mask)
+			break;
+		shift++;
+	} while (1);
+		
+	mmap_map_mask = 1UL << shift;
+	return 0;
+}
+
 static struct ioengine_ops ioengine = {
 	.name		= "mmap",
 	.version	= FIO_IOOPS_VERSION,
+	.init		= fio_mmapio_init,
+	.prep		= fio_mmapio_prep,
 	.queue		= fio_mmapio_queue,
-	.flags		= FIO_SYNCIO | FIO_MMAPIO,
+	.open_file	= generic_open_file,
+	.close_file	= generic_close_file,
+	.get_file_size	= generic_get_file_size,
+	.flags		= FIO_SYNCIO | FIO_NOEXTEND,
 };
 
 static void fio_init fio_mmapio_register(void)