diff --git a/ompi/mca/fbtl/posix/fbtl_posix.c b/ompi/mca/fbtl/posix/fbtl_posix.c
index 4c6d21ab01..29dbdb4197 100644
--- a/ompi/mca/fbtl/posix/fbtl_posix.c
+++ b/ompi/mca/fbtl/posix/fbtl_posix.c
@@ -118,6 +118,7 @@ bool mca_fbtl_posix_progress ( mca_ompio_request_t *req)
 #if defined (FBTL_POSIX_HAVE_AIO)
     int i=0, lcount=0;
     mca_fbtl_posix_request_data_t *data=(mca_fbtl_posix_request_data_t *)req->req_data;
+    off_t start_offset, end_offset, total_length;
 
     for (i=data->aio_first_active_req; i < data->aio_last_active_req; i++ ) {
 	if ( EINPROGRESS == data->aio_req_status[i] ) {
@@ -154,6 +155,9 @@ bool mca_fbtl_posix_progress ( mca_ompio_request_t *req)
 #endif
 
     if ( (lcount == data->aio_req_chunks) && (0 != data->aio_open_reqs )) {
+        /* release the lock of the previous operations */
+        mca_fbtl_posix_unlock ( &data->aio_lock, data->aio_fh );
+        
 	/* post the next batch of operations */
 	data->aio_first_active_req = data->aio_last_active_req;
 	if ( (data->aio_req_count-data->aio_last_active_req) > data->aio_req_chunks ) {
@@ -162,16 +166,30 @@ bool mca_fbtl_posix_progress ( mca_ompio_request_t *req)
 	else {
 	    data->aio_last_active_req = data->aio_req_count;
 	}
+
+        start_offset = data->aio_reqs[data->aio_first_active_req].aio_offset;
+        end_offset   = data->aio_reqs[data->aio_last_active_req-1].aio_offset + data->aio_reqs[data->aio_last_active_req-1].aio_nbytes;
+        total_length = (end_offset - start_offset);
+
+        if ( FBTL_POSIX_READ == data->aio_req_type ) {
+            mca_fbtl_posix_lock( &data->aio_lock, data->aio_fh, F_RDLCK, start_offset, total_length, OMPIO_LOCK_ENTIRE_REGION );
+        }
+        else if ( FBTL_POSIX_WRITE == data->aio_req_type ) {
+            mca_fbtl_posix_lock( &data->aio_lock, data->aio_fh, F_WRLCK, start_offset, total_length, OMPIO_LOCK_ENTIRE_REGION );
+        }
+
 	for ( i=data->aio_first_active_req; i< data->aio_last_active_req; i++ ) {
 	    if ( FBTL_POSIX_READ == data->aio_req_type ) {
 		if (-1 == aio_read(&data->aio_reqs[i])) {
 		    perror("aio_read() error");
+                    mca_fbtl_posix_unlock ( &data->aio_lock, data->aio_fh );
 		    return OMPI_ERROR;
 		}
 	    }
 	    else if ( FBTL_POSIX_WRITE == data->aio_req_type ) {
 		if (-1 == aio_write(&data->aio_reqs[i])) {
 		    perror("aio_write() error");
+                    mca_fbtl_posix_unlock ( &data->aio_lock, data->aio_fh );
 		    return OMPI_ERROR;
 		}
 	    }
diff --git a/ompi/mca/fbtl/posix/fbtl_posix.h b/ompi/mca/fbtl/posix/fbtl_posix.h
index b9353a921a..b4d029dd96 100644
--- a/ompi/mca/fbtl/posix/fbtl_posix.h
+++ b/ompi/mca/fbtl/posix/fbtl_posix.h
@@ -73,6 +73,8 @@ struct mca_fbtl_posix_request_data_t {
     struct aiocb       *aio_reqs;       /* pointer array of req structures */
     int          *aio_req_status;       /* array of statuses */
     ssize_t        aio_total_len;       /* total amount of data written */
+    struct flock   aio_lock;            /* lock used for certain file systems */
+    mca_io_ompio_file_t  *aio_fh;       /* pointer back to the mca_io_ompio_fh structure */
 };
 typedef struct mca_fbtl_posix_request_data_t mca_fbtl_posix_request_data_t;
 
diff --git a/ompi/mca/fbtl/posix/fbtl_posix_ipreadv.c b/ompi/mca/fbtl/posix/fbtl_posix_ipreadv.c
index 00eaedeaf7..6ac9d03703 100644
--- a/ompi/mca/fbtl/posix/fbtl_posix_ipreadv.c
+++ b/ompi/mca/fbtl/posix/fbtl_posix_ipreadv.c
@@ -40,6 +40,7 @@ ssize_t mca_fbtl_posix_ipreadv (mca_io_ompio_file_t *fh,
     mca_fbtl_posix_request_data_t *data;
     mca_ompio_request_t *req = (mca_ompio_request_t *) request;
     int i=0;
+    off_t start_offset, end_offset, total_length;
 
     data = (mca_fbtl_posix_request_data_t *) malloc ( sizeof (mca_fbtl_posix_request_data_t));
     if ( NULL == data ) {
@@ -67,6 +68,7 @@ ssize_t mca_fbtl_posix_ipreadv (mca_io_ompio_file_t *fh,
         free(data);
         return 0;
     }
+    data->aio_fh = fh;
 
     for ( i=0; i<fh->f_num_of_io_entries; i++ ) {
         data->aio_reqs[i].aio_offset  = (OMPI_MPI_OFFSET_TYPE)(intptr_t)
@@ -86,9 +88,16 @@ ssize_t mca_fbtl_posix_ipreadv (mca_io_ompio_file_t *fh,
     else {
 	data->aio_last_active_req = data->aio_req_count;
     }
+
+    start_offset = data->aio_reqs[data->aio_first_active_req].aio_offset;
+    end_offset   = data->aio_reqs[data->aio_last_active_req-1].aio_offset + data->aio_reqs[data->aio_last_active_req-1].aio_nbytes;
+    total_length = (end_offset - start_offset);
+    mca_fbtl_posix_lock( &data->aio_lock, data->aio_fh, F_RDLCK, start_offset, total_length, OMPIO_LOCK_ENTIRE_REGION );
+
     for (i=0; i < data->aio_last_active_req; i++) {
         if (-1 == aio_read(&data->aio_reqs[i])) {
             opal_output(1, "aio_read() error: %s", strerror(errno));
+            mca_fbtl_posix_unlock ( &data->aio_lock, data->aio_fh );            
             free(data->aio_reqs);
             free(data->aio_req_status);
             free(data);
diff --git a/ompi/mca/fbtl/posix/fbtl_posix_ipwritev.c b/ompi/mca/fbtl/posix/fbtl_posix_ipwritev.c
index 1d869c2a75..2bd04ff747 100644
--- a/ompi/mca/fbtl/posix/fbtl_posix_ipwritev.c
+++ b/ompi/mca/fbtl/posix/fbtl_posix_ipwritev.c
@@ -39,6 +39,7 @@ ssize_t  mca_fbtl_posix_ipwritev (mca_io_ompio_file_t *fh,
     mca_fbtl_posix_request_data_t *data;
     mca_ompio_request_t *req = (mca_ompio_request_t *) request;
     int i=0;
+    off_t start_offset, end_offset, total_length;
 
     data = (mca_fbtl_posix_request_data_t *) malloc ( sizeof (mca_fbtl_posix_request_data_t));
     if ( NULL == data ) {
@@ -66,6 +67,7 @@ ssize_t  mca_fbtl_posix_ipwritev (mca_io_ompio_file_t *fh,
         free(data);
         return 0;
     }
+    data->aio_fh = fh;
 
     for ( i=0; i<fh->f_num_of_io_entries; i++ ) {
         data->aio_reqs[i].aio_offset  = (OMPI_MPI_OFFSET_TYPE)(intptr_t)
@@ -85,10 +87,16 @@ ssize_t  mca_fbtl_posix_ipwritev (mca_io_ompio_file_t *fh,
     else {
 	data->aio_last_active_req = data->aio_req_count;
     }
+    
+    start_offset = data->aio_reqs[data->aio_first_active_req].aio_offset;
+    end_offset   = data->aio_reqs[data->aio_last_active_req-1].aio_offset + data->aio_reqs[data->aio_last_active_req-1].aio_nbytes;
+    total_length = (end_offset - start_offset);
+    mca_fbtl_posix_lock( &data->aio_lock, data->aio_fh, F_WRLCK, start_offset, total_length, OMPIO_LOCK_ENTIRE_REGION );
 
     for (i=0; i < data->aio_last_active_req; i++) {
         if (-1 == aio_write(&data->aio_reqs[i])) {
             opal_output(1, "aio_write() error: %s", strerror(errno));
+            mca_fbtl_posix_unlock ( &data->aio_lock, data->aio_fh );                    
             free(data->aio_req_status);
             free(data->aio_reqs);
             free(data);
diff --git a/ompi/mca/fbtl/posix/fbtl_posix_preadv.c b/ompi/mca/fbtl/posix/fbtl_posix_preadv.c
index cbf9d34fb9..b6360b3d97 100644
--- a/ompi/mca/fbtl/posix/fbtl_posix_preadv.c
+++ b/ompi/mca/fbtl/posix/fbtl_posix_preadv.c
@@ -55,7 +55,6 @@ ssize_t mca_fbtl_posix_preadv (mca_io_ompio_file_t *fh )
 	    iov[iov_count].iov_base = fh->f_io_array[i].memory_address;
 	    iov[iov_count].iov_len = fh->f_io_array[i].length;
 	    iov_offset = (OMPI_MPI_OFFSET_TYPE)(intptr_t)fh->f_io_array[i].offset;
-            total_length = iov[iov_count].iov_len;
 	    iov_count ++;
 	}
 
@@ -78,11 +77,12 @@ ssize_t mca_fbtl_posix_preadv (mca_io_ompio_file_t *fh )
                     iov[iov_count].iov_base =
                         fh->f_io_array[i+1].memory_address;
                     iov[iov_count].iov_len = fh->f_io_array[i+1].length;
-                    total_length += iov[iov_count].iov_len;
                     iov_count ++;
                     continue;
 	    }
 	}
+
+        total_length = ((off_t)iov[iov_count-1].iov_base + iov[iov_count-1].iov_len - (off_t)iov_offset );
         mca_fbtl_posix_lock ( &lock, fh, F_RDLCK, iov_offset, total_length, OMPIO_LOCK_SELECTIVE ); 
 #if defined(HAVE_PREADV)
 	ret_code = preadv (fh->fd, iov, iov_count, iov_offset);
diff --git a/ompi/mca/fbtl/posix/fbtl_posix_pwritev.c b/ompi/mca/fbtl/posix/fbtl_posix_pwritev.c
index da7c31e959..61d8008355 100644
--- a/ompi/mca/fbtl/posix/fbtl_posix_pwritev.c
+++ b/ompi/mca/fbtl/posix/fbtl_posix_pwritev.c
@@ -57,7 +57,6 @@ ssize_t  mca_fbtl_posix_pwritev(mca_io_ompio_file_t *fh )
 	    iov[iov_count].iov_base = fh->f_io_array[i].memory_address;
 	    iov[iov_count].iov_len = fh->f_io_array[i].length;
 	    iov_offset = (OMPI_MPI_OFFSET_TYPE)(intptr_t)fh->f_io_array[i].offset;
-            total_length = iov[iov_count].iov_len;
 	    iov_count ++;
 	}
 
@@ -79,7 +78,6 @@ ssize_t  mca_fbtl_posix_pwritev(mca_io_ompio_file_t *fh )
 		 (iov_count < IOV_MAX )) {
 		iov[iov_count].iov_base = fh->f_io_array[i+1].memory_address;
 		iov[iov_count].iov_len  = fh->f_io_array[i+1].length;
-                total_length += iov[iov_count].iov_len;
                 iov_count ++;
 		continue;
 	    }
@@ -97,6 +95,7 @@ ssize_t  mca_fbtl_posix_pwritev(mca_io_ompio_file_t *fh )
 
 	*/
 
+        total_length = ((off_t)iov[iov_count-1].iov_base + iov[iov_count-1].iov_len - (off_t)iov_offset);
         mca_fbtl_posix_lock ( &lock, fh, F_WRLCK, iov_offset, total_length, OMPIO_LOCK_SELECTIVE ); 
 #if defined (HAVE_PWRITEV) 
 	ret_code = pwritev (fh->fd, iov, iov_count, iov_offset);