bd: Add aio support to BD xlator

Volume option bd-aio controls AIO feature for BD xlator. Code taken from
posix-aio.c

Change-Id: Ib049bd59c9d3f9101d33939838322cfa808de053
BUG: 1028672
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Reviewed-on: http://review.gluster.org/5748
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>

6 files changed, 647 insertions, 24 deletions

diff --git a/xlators/storage/bd/src/Makefile.am b/xlators/storage/bd/src/Makefile.am
index 210b7453af8..3d93f744295 100644
--- a/xlators/storage/bd/src/Makefile.am
+++ b/xlators/storage/bd/src/Makefile.am
@@ -4,10 +4,10 @@ xlatordir = $(libdir)/glusterfs/$(PACKAGE_VERSION)/xlator/storage
 
 bd_la_LDFLAGS = -module -avoid-version
 LIBBD = -llvm2app -lrt
-bd_la_SOURCES = bd.c bd-helper.c
-bd_la_LIBADD = $(top_builddir)/libglusterfs/src/libglusterfs.la $(LIBBD)
+bd_la_SOURCES = bd.c bd-helper.c bd-aio.c
+bd_la_LIBADD = $(top_builddir)/libglusterfs/src/libglusterfs.la $(LIBBD) $(LIBAIO)
 
-noinst_HEADERS = bd.h
+noinst_HEADERS = bd.h bd-aio.h
 
 AM_CPPFLAGS = $(GF_CPPFLAGS) -I$(top_srcdir)/libglusterfs/src \
             -I$(top_srcdir)/rpc/xdr/src \
diff --git a/xlators/storage/bd/src/bd-aio.c b/xlators/storage/bd/src/bd-aio.c
new file mode 100644
index 00000000000..62d4590f728
--- /dev/null
+++ b/xlators/storage/bd/src/bd-aio.c
@@ -0,0 +1,527 @@
+/*
+  Copyright IBM, Corp. 2013
+
+  This file is part of GlusterFS.
+
+  Author: M. Mohan Kumar <mohan@in.ibm.com>
+
+  Based on posix-aio.c
+
+  This file is licensed to you under your choice of the GNU Lesser
+  General Public License, version 3 or any later version (LGPLv3 or
+  later), or the GNU General Public License, version 2 (GPLv2), in all
+  cases as published by the Free Software Foundation.
+*/
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include <lvm2app.h>
+#include <sys/uio.h>
+
+#include "xlator.h"
+#include "glusterfs.h"
+#include "defaults.h"
+#include "bd.h"
+#include "bd-aio.h"
+
+#ifdef HAVE_LIBAIO
+#include <libaio.h>
+
+struct bd_aio_cb {
+        struct iocb     iocb;
+        call_frame_t   *frame;
+        struct iobuf   *iobuf;
+        struct iobref  *iobref;
+        struct iatt     prebuf;
+        int             op;
+        off_t           offset;
+        fd_t           *fd;
+};
+
+void
+__bd_fd_set_odirect (fd_t *fd, bd_fd_t *bd_fd, int opflags,
+                     off_t offset, size_t size)
+{
+        int odirect = 0;
+        int flags = 0;
+        int ret = 0;
+
+        odirect = bd_fd->odirect;
+
+        if ((fd->flags|opflags) & O_DIRECT) {
+                /* if instructed, use O_DIRECT always */
+                odirect = 1;
+        } else {
+                /* else use O_DIRECT when feasible */
+                if ((offset|size) & 0xfff)
+                        odirect = 0;
+                else
+                        odirect = 1;
+        }
+
+        if (!odirect && bd_fd->odirect) {
+                flags = fcntl (bd_fd->fd, F_GETFL);
+                ret = fcntl (bd_fd->fd, F_SETFL, (flags & (~O_DIRECT)));
+                bd_fd->odirect = 0;
+        }
+
+        if (odirect && !bd_fd->odirect) {
+                flags = fcntl (bd_fd->fd, F_GETFL);
+                ret = fcntl (bd_fd->fd, F_SETFL, (flags | O_DIRECT));
+                bd_fd->odirect = 1;
+        }
+
+        if (ret) {
+                gf_log (THIS->name, GF_LOG_WARNING,
+                        "fcntl() failed (%s). fd=%d flags=%d pfd->odirect=%d",
+                        strerror (errno), bd_fd->fd, flags, bd_fd->odirect);
+        }
+}
+
+int
+bd_aio_readv_complete (struct bd_aio_cb *paiocb, int res, int res2)
+{
+        call_frame_t   *frame = NULL;
+        xlator_t       *this = NULL;
+        struct iobuf   *iobuf = NULL;
+        struct iatt     postbuf = {0,};
+        int             op_ret = -1;
+        int             op_errno = 0;
+        struct iovec    iov;
+        struct iobref  *iobref = NULL;
+        off_t           offset = 0;
+        bd_attr_t      *bdatt = NULL;
+
+        frame = paiocb->frame;
+        this = frame->this;
+        iobuf = paiocb->iobuf;
+        offset = paiocb->offset;
+
+        if (res < 0) {
+                op_ret = -1;
+                op_errno = -res;
+                gf_log (this->name, GF_LOG_ERROR,
+                        "readv(async) failed fd=%p,size=%lu,offset=%llu (%d/%s)",
+                        paiocb->fd, paiocb->iocb.u.c.nbytes,
+                        (unsigned long long) paiocb->offset,
+                        res, strerror (op_errno));
+                goto out;
+        }
+
+        bd_inode_ctx_get (paiocb->fd->inode, this, &bdatt);
+        memcpy (&postbuf, &bdatt->iatt, sizeof (struct iatt));
+
+        op_ret = res;
+        op_errno = 0;
+
+        iobref = iobref_new ();
+        if (!iobref) {
+                op_ret = -1;
+                op_errno = ENOMEM;
+                goto out;
+        }
+
+        iobref_add (iobref, iobuf);
+
+        iov.iov_base = iobuf_ptr (iobuf);
+        iov.iov_len = op_ret;
+
+        /* Hack to notify higher layers of EOF. */
+        if (!postbuf.ia_size || (offset + iov.iov_len) >= postbuf.ia_size)
+                op_errno = ENOENT;
+
+out:
+        STACK_UNWIND_STRICT (readv, frame, op_ret, op_errno, &iov, 1,
+                             &postbuf, iobref, NULL);
+        if (iobuf)
+                iobuf_unref (iobuf);
+        if (iobref)
+                iobref_unref (iobref);
+
+        GF_FREE (paiocb);
+
+        return 0;
+}
+
+int
+bd_aio_readv (call_frame_t *frame, xlator_t *this, fd_t *fd,
+                 size_t size, off_t offset, uint32_t flags, dict_t *xdata)
+{
+        int32_t             op_errno   = EINVAL;
+        int                 _fd        = -1;
+        struct iobuf       *iobuf      = NULL;
+        bd_fd_t            *bd_fd      = NULL;
+        int                 ret        = -1;
+        struct bd_aio_cb   *paiocb     = NULL;
+        bd_priv_t          *priv       = NULL;
+        struct iocb        *iocb       = NULL;
+        bd_attr_t          *bdatt      = NULL;
+
+        VALIDATE_OR_GOTO (frame, err);
+        VALIDATE_OR_GOTO (this, err);
+        VALIDATE_OR_GOTO (fd, err);
+
+        priv = this->private;
+
+        ret = bd_fd_ctx_get (this, fd, &bd_fd);
+        if (ret < 0 || !bd_fd) {
+                STACK_WIND (frame, default_readv_cbk, FIRST_CHILD (this),
+                            FIRST_CHILD (this)->fops->readv, fd, size, offset,
+                            flags, xdata);
+                return 0;
+        }
+        _fd = bd_fd->fd;
+        bd_inode_ctx_get (fd->inode, this, &bdatt);
+        if (!size) {
+                op_errno = EINVAL;
+                gf_log (this->name, GF_LOG_WARNING, "size=%"GF_PRI_SIZET, size);
+                goto err;
+        }
+
+        iobuf = iobuf_get2 (this->ctx->iobuf_pool, size);
+        if (!iobuf) {
+                op_errno = ENOMEM;
+                goto err;
+        }
+
+        paiocb = CALLOC (1, sizeof (*paiocb));
+        if (!paiocb) {
+                op_errno = ENOMEM;
+                goto err;
+        }
+
+        paiocb->frame = frame;
+        paiocb->iobuf = iobuf;
+        paiocb->offset = offset;
+        paiocb->op = GF_FOP_READ;
+        paiocb->fd = fd;
+
+        paiocb->iocb.data = paiocb;
+        paiocb->iocb.aio_fildes = _fd;
+        paiocb->iocb.aio_lio_opcode = IO_CMD_PREAD;
+        paiocb->iocb.aio_reqprio = 0;
+        paiocb->iocb.u.c.buf = iobuf_ptr (iobuf);
+        paiocb->iocb.u.c.nbytes = size;
+        paiocb->iocb.u.c.offset = offset;
+
+        iocb = &paiocb->iocb;
+
+        LOCK (&fd->lock);
+        {
+                __bd_fd_set_odirect (fd, bd_fd, flags, offset, size);
+
+                ret = io_submit (priv->ctxp, 1, &iocb);
+        }
+        UNLOCK (&fd->lock);
+
+        if (ret != 1) {
+                gf_log (this->name, GF_LOG_ERROR,
+                        "io_submit() returned %d", ret);
+                op_errno = -ret;
+                goto err;
+        }
+
+        return 0;
+err:
+        STACK_UNWIND_STRICT (readv, frame, -1, op_errno, 0, 0, 0, 0, 0);
+        if (iobuf)
+                iobuf_unref (iobuf);
+
+        if (paiocb)
+                GF_FREE (paiocb);
+
+        return 0;
+}
+
+int
+bd_aio_writev_complete (struct bd_aio_cb *paiocb, int res, int res2)
+{
+        call_frame_t *frame    = NULL;
+        xlator_t     *this     = NULL;
+        struct iatt   prebuf   = {0,};
+        struct iatt   postbuf  = {0,};
+        int           op_ret   = -1;
+        int           op_errno = 0;
+        bd_attr_t    *bdatt    = NULL;
+
+        frame = paiocb->frame;
+        prebuf = paiocb->prebuf;
+        this = frame->this;
+
+        if (res < 0) {
+                op_ret = -1;
+                op_errno = -res;
+                gf_log (this->name, GF_LOG_ERROR,
+                        "writev(async) failed fd=%p,offset=%llu (%d/%s)",
+                        paiocb->fd, (unsigned long long) paiocb->offset, res,
+                        strerror (op_errno));
+
+                goto out;
+        }
+
+        bd_inode_ctx_get (paiocb->fd->inode, this, &bdatt);
+        bd_update_amtime (&bdatt->iatt, GF_SET_ATTR_MTIME);
+        memcpy (&postbuf, &bdatt->iatt, sizeof (struct iatt));
+
+        op_ret = res;
+        op_errno = 0;
+
+out:
+        STACK_UNWIND_STRICT (writev, frame, op_ret, op_errno, &prebuf, &postbuf,
+                             NULL);
+
+        if (paiocb) {
+                if (paiocb->iobref)
+                        iobref_unref (paiocb->iobref);
+                GF_FREE (paiocb);
+        }
+
+        return 0;
+}
+
+int
+bd_aio_writev (call_frame_t *frame, xlator_t *this, fd_t *fd,
+               struct iovec *iov, int count, off_t offset, uint32_t flags,
+               struct iobref *iobref, dict_t *xdata)
+{
+        int32_t             op_errno   = EINVAL;
+        int                 _fd        = -1;
+        bd_fd_t            *bd_fd      = NULL;
+        int                 ret        = -1;
+        struct bd_aio_cb   *paiocb     = NULL;
+        bd_priv_t          *priv       = NULL;
+        struct iocb        *iocb       = NULL;
+        bd_attr_t          *bdatt      = NULL;
+
+        VALIDATE_OR_GOTO (frame, err);
+        VALIDATE_OR_GOTO (this, err);
+        VALIDATE_OR_GOTO (fd, err);
+
+        priv = this->private;
+
+        ret = bd_fd_ctx_get (this, fd, &bd_fd);
+        if (ret < 0 || !bd_fd) {
+                STACK_WIND (frame, default_writev_cbk,
+                            FIRST_CHILD(this), FIRST_CHILD(this)->fops->writev,
+                            fd, iov, count, offset, flags, iobref, xdata);
+                return 0;
+        }
+
+        bd_inode_ctx_get (fd->inode, this, &bdatt);
+
+        _fd = bd_fd->fd;
+
+        paiocb = CALLOC (1, sizeof (*paiocb));
+        if (!paiocb) {
+                op_errno = ENOMEM;
+                goto err;
+        }
+
+
+        paiocb->frame = frame;
+        paiocb->offset = offset;
+        paiocb->op = GF_FOP_WRITE;
+        paiocb->fd = fd;
+
+        paiocb->iocb.data = paiocb;
+        paiocb->iocb.aio_fildes = _fd;
+        paiocb->iobref = iobref_ref (iobref);
+        paiocb->iocb.aio_lio_opcode = IO_CMD_PWRITEV;
+        paiocb->iocb.aio_reqprio = 0;
+        paiocb->iocb.u.v.vec = iov;
+        paiocb->iocb.u.v.nr = count;
+        paiocb->iocb.u.v.offset = offset;
+
+        iocb = &paiocb->iocb;
+
+        memcpy (&paiocb->prebuf, &bdatt->iatt, sizeof (struct iatt));
+        LOCK (&fd->lock);
+        {
+                __bd_fd_set_odirect (fd, bd_fd, flags, offset,
+                                     iov_length (iov, count));
+
+                ret = io_submit (priv->ctxp, 1, &iocb);
+        }
+        UNLOCK (&fd->lock);
+
+        if (ret != 1) {
+                gf_log (this->name, GF_LOG_ERROR,
+                        "io_submit() returned %d", ret);
+                op_errno = -ret;
+                goto err;
+        }
+
+        return 0;
+err:
+        STACK_UNWIND_STRICT (writev, frame, -1, op_errno, 0, 0, 0);
+
+        if (paiocb) {
+                if (paiocb->iobref)
+                        iobref_unref (paiocb->iobref);
+                GF_FREE (paiocb);
+        }
+
+        return 0;
+}
+
+void *
+bd_aio_thread (void *data)
+{
+        xlator_t           *this = NULL;
+        bd_priv_t          *priv = NULL;
+        int                 ret = 0;
+        int                 i = 0;
+        struct io_event    *event = NULL;
+        struct bd_aio_cb   *paiocb = NULL;
+        struct io_event     events[BD_AIO_MAX_NR_GETEVENTS];
+        struct timespec     ts = {0, };
+
+        this = data;
+        THIS = this;
+        priv = this->private;
+
+        ts.tv_sec = 5;
+        for (;;) {
+                memset (&events[0], 0, sizeof (events));
+                ret = io_getevents (priv->ctxp, 1, BD_AIO_MAX_NR_GETEVENTS,
+                                    &events[0], &ts);
+                if (ret < 0) {
+                        if (ret == -EINTR)
+                                continue;
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "io_getevents() returned %d, exiting", ret);
+                        break;
+                }
+
+                for (i = 0; i < ret; i++) {
+                        event = &events[i];
+
+                        paiocb = event->data;
+
+                        switch (paiocb->op) {
+                        case GF_FOP_READ:
+                                bd_aio_readv_complete (paiocb, event->res,
+                                                          event->res2);
+                                break;
+                        case GF_FOP_WRITE:
+                                bd_aio_writev_complete (paiocb, event->res,
+                                                           event->res2);
+                                break;
+                        default:
+                                gf_log (this->name, GF_LOG_ERROR,
+                                        "unknown op %d found in piocb",
+                                        paiocb->op);
+                                break;
+                        }
+                }
+        }
+
+        return NULL;
+}
+
+int
+bd_aio_init (xlator_t *this)
+{
+        bd_priv_t *priv = NULL;
+        int        ret = 0;
+
+        priv = this->private;
+
+        ret = io_setup (BD_AIO_MAX_NR_EVENTS, &priv->ctxp);
+        if ((ret == -1 && errno == ENOSYS) || ret == -ENOSYS) {
+                gf_log (this->name, GF_LOG_WARNING,
+                        "Linux AIO not available at run-time."
+                        " Continuing with synchronous IO");
+                ret = 0;
+                goto out;
+        }
+
+        if (ret < 0) {
+                gf_log (this->name, GF_LOG_WARNING,
+                        "io_setup() failed. ret=%d, errno=%d",
+                        ret, errno);
+                goto out;
+        }
+
+        ret = pthread_create (&priv->aiothread, NULL,
+                              bd_aio_thread, this);
+        if (ret != 0) {
+                io_destroy (priv->ctxp);
+                goto out;
+        }
+
+        this->fops->readv  = bd_aio_readv;
+        this->fops->writev = bd_aio_writev;
+out:
+        return ret;
+}
+
+
+int
+bd_aio_on (xlator_t *this)
+{
+        bd_priv_t *priv = NULL;
+        int        ret = 0;
+
+        priv = this->private;
+
+        if (!priv->aio_init_done) {
+                ret = bd_aio_init (this);
+                if (ret == 0)
+                        priv->aio_capable = _gf_true;
+                else
+                        priv->aio_capable = _gf_false;
+                priv->aio_init_done = _gf_true;
+        }
+
+        if (priv->aio_capable) {
+                this->fops->readv  = bd_aio_readv;
+                this->fops->writev = bd_aio_writev;
+        }
+
+        return ret;
+}
+
+int
+bd_aio_off (xlator_t *this)
+{
+        this->fops->readv  = bd_readv;
+        this->fops->writev = bd_writev;
+
+        return 0;
+}
+
+#else
+
+int
+bd_aio_on (xlator_t *this)
+{
+        gf_log (this->name, GF_LOG_INFO,
+                "Linux AIO not available at build-time."
+                " Continuing with synchronous IO");
+        return 0;
+}
+
+int
+bd_aio_off (xlator_t *this)
+{
+        gf_log (this->name, GF_LOG_INFO,
+                "Linux AIO not available at build-time."
+                " Continuing with synchronous IO");
+        return 0;
+}
+
+void
+__bd_fd_set_odirect (fd_t *fd, struct bd_fd *pfd, int opflags,
+                        off_t offset, size_t size)
+{
+        xlator_t        *this = THIS;
+        gf_log (this->name, GF_LOG_INFO,
+                "Linux AIO not available at build-time."
+                " Continuing with synchronous IO");
+        return;
+}
+#endif
diff --git a/xlators/storage/bd/src/bd-aio.h b/xlators/storage/bd/src/bd-aio.h
new file mode 100644
index 00000000000..16f686a4caa
--- /dev/null
+++ b/xlators/storage/bd/src/bd-aio.h
@@ -0,0 +1,41 @@
+/*
+   Copyright IBM, Corp. 2013
+
+   This file is part of GlusterFS.
+
+   This file is licensed to you under your choice of the GNU Lesser
+   General Public License, version 3 or any later version (LGPLv3 or
+   later), or the GNU General Public License, version 2 (GPLv2), in all
+   cases as published by the Free Software Foundation.
+*/
+#ifndef _BD_AIO_H
+#define _BD_AIO_H
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "xlator.h"
+#include "glusterfs.h"
+
+/*
+ * Maximum number of concurrently submitted IO events. The heaviest load
+ * GlusterFS has been able to handle had 60-80 concurrent calls
+ */
+#define BD_AIO_MAX_NR_EVENTS 256
+
+/* Maximum number of completed IO operations to reap per getevents syscall */
+#define BD_AIO_MAX_NR_GETEVENTS 16
+
+int bd_aio_on (xlator_t *this);
+int bd_aio_off (xlator_t *this);
+
+int bd_readv (call_frame_t *frame, xlator_t *this, fd_t *fd, size_t size,
+                      off_t offset, uint32_t flags, dict_t *xdata);
+
+int bd_writev (call_frame_t *frame, xlator_t *this, fd_t *fd,
+                       struct iovec *vector, int32_t count, off_t offset,
+                       uint32_t flags, struct iobref *iobref, dict_t *xdata);
+
+#endif /* !_BD_AIO_H */
diff --git a/xlators/storage/bd/src/bd-helper.c b/xlators/storage/bd/src/bd-helper.c
index 2c1b77a9b3e..8781f9fdfb4 100644
--- a/xlators/storage/bd/src/bd-helper.c
+++ b/xlators/storage/bd/src/bd-helper.c
@@ -3,6 +3,9 @@
 #include "config.h"
 #endif
 #include <lvm2app.h>
+#ifdef HAVE_LIBAIO
+#include <libaio.h>
+#endif
 
 #include "bd.h"
 #include "run.h"
@@ -560,3 +563,19 @@ out:
 
         return ret;
 }
+
+inline void
+bd_update_amtime(struct iatt *iatt, int flag)
+{
+        struct timespec ts = {0, };
+
+        clock_gettime (CLOCK_REALTIME, &ts);
+        if (flag & GF_SET_ATTR_ATIME) {
+                iatt->ia_atime = ts.tv_sec;
+                iatt->ia_atime_nsec = ts.tv_nsec;
+        }
+        if (flag & GF_SET_ATTR_MTIME) {
+                iatt->ia_mtime = ts.tv_sec;
+                iatt->ia_mtime_nsec = ts.tv_nsec;
+        }
+}
diff --git a/xlators/storage/bd/src/bd.c b/xlators/storage/bd/src/bd.c
index 5fa15c542c0..555f1d51fc1 100644
--- a/xlators/storage/bd/src/bd.c
+++ b/xlators/storage/bd/src/bd.c
@@ -26,8 +26,12 @@
 #include <time.h>
 #include <linux/fs.h>
 #include <sys/ioctl.h>
+#ifdef HAVE_LIBAIO
+#include <libaio.h>
+#endif
 
 #include "bd.h"
+#include "bd-aio.h"
 #include "defaults.h"
 #include "glusterfs3-xdr.h"
 #include "run.h"
@@ -440,22 +444,6 @@ out:
         return 0;
 }
 
-static inline void
-bd_update_amtime (struct iatt *iatt, int flag)
-{
-        struct timespec ts         = {0, };
-
-        clock_gettime (CLOCK_REALTIME, &ts);
-        if (flag & GF_SET_ATTR_ATIME) {
-                iatt->ia_atime = ts.tv_sec;
-                iatt->ia_atime_nsec = ts.tv_nsec;
-        }
-        if (flag & GF_SET_ATTR_MTIME) {
-                iatt->ia_mtime = ts.tv_sec;
-                iatt->ia_mtime_nsec = ts.tv_nsec;
-        }
-}
-
 /*
  * bd_readv: If posix file, invokes posix_readv otherwise reads from the BD
  * file
@@ -680,6 +668,7 @@ bd_open (call_frame_t *frame, xlator_t *this, loc_t *loc, int32_t flags,
 
         bd_fd->fd = _fd;
         bd_fd->flag = flags | O_LARGEFILE;
+
         if (fd_ctx_set (fd, this, (uint64_t)(long)bd_fd) < 0) {
                 gf_log (this->name, GF_LOG_WARNING,
                         "failed to set the fd context fd=%p", fd);
@@ -1918,6 +1907,25 @@ mem_acct_init (xlator_t *this)
         return ret;
 }
 
+int
+reconfigure (xlator_t *this, dict_t *options)
+{
+        int   ret = -1;
+        bd_priv_t *priv = this->private;
+
+        GF_OPTION_RECONF ("bd-aio", priv->aio_configured, options,
+                          bool, out);
+
+        if (priv->aio_configured)
+                bd_aio_on (this);
+        else
+                bd_aio_off (this);
+
+        ret = 0;
+out:
+        return ret;
+}
+
 /**
  * bd xlator init - Validate configured VG
  */
@@ -1976,6 +1984,19 @@ init (xlator_t *this)
         if (bd_scan_vg (this, _private))
                 goto error;
 
+        _private->aio_init_done = _gf_false;
+        _private->aio_capable = _gf_false;
+
+        GF_OPTION_INIT ("bd-aio", _private->aio_configured, bool, error);
+        if (_private->aio_configured) {
+                if (bd_aio_on (this)) {
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "BD AIO init failed");
+                        ret = -1;
+                        goto error;
+                }
+        }
+
         return 0;
 error:
         GF_FREE (_private->vg);
@@ -2043,5 +2064,12 @@ struct volume_options options[] = {
         { .key = {"device"},
           .type = GF_OPTION_TYPE_STR,
           .default_value = BACKEND_VG},
+        {
+          .key  = {"bd-aio"},
+          .type = GF_OPTION_TYPE_BOOL,
+          .default_value = "off",
+          .description = "Support for native Linux AIO"
+        },
+
         { .key = {NULL} }
 };
diff --git a/xlators/storage/bd/src/bd.h b/xlators/storage/bd/src/bd.h
index 4d8b8954524..e3acdedc1d2 100644
--- a/xlators/storage/bd/src/bd.h
+++ b/xlators/storage/bd/src/bd.h
@@ -23,6 +23,10 @@
 #include "config.h"
 #endif
 
+#ifdef HAVE_LIBAIO
+#include <libaio.h>
+#endif
+
 #include "xlator.h"
 #include "mem-types.h"
 
@@ -83,6 +87,7 @@ enum gf_bd_mem_types_ {
 typedef struct bd_fd {
         int             fd;
         int32_t         flag;
+        int             odirect;
 } bd_fd_t;
 
 typedef struct bd_priv {
@@ -90,6 +95,13 @@ typedef struct bd_priv {
         char              *vg;
         char              *pool;
         int                caps;
+        gf_boolean_t       aio_init_done;
+        gf_boolean_t       aio_capable;
+        gf_boolean_t       aio_configured;
+#ifdef HAVE_LIBAIO
+        io_context_t       ctxp;
+        pthread_t          aiothread;
+#endif
 } bd_priv_t;
 
 
@@ -112,11 +124,6 @@ typedef struct {
         data_t      *data; /* for setxattr */
 } bd_local_t;
 
-typedef struct {
-        char            *lv;
-        struct list_head list;
-} bd_del_entry;
-
 /* Prototypes */
 int bd_inode_ctx_set (inode_t *inode, xlator_t *this, bd_attr_t *ctx);
 int bd_inode_ctx_get (inode_t *inode, xlator_t *this, bd_attr_t **ctx);
@@ -137,4 +144,5 @@ int bd_clone (bd_local_t *local, bd_priv_t *priv);
 
 int bd_merge (bd_priv_t *priv, uuid_t gfid);
 int bd_get_origin (bd_priv_t *priv, loc_t *loc, fd_t *fd, dict_t *dict);
+inline void bd_update_amtime(struct iatt *iatt, int flag);
 #endif