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libs/ck-libs/ampi/romio/adio/ad_xfs/ad_xfs_write.c

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/* -*- Mode: C; c-basic-offset:4 ; -*- */
/* 
 *
 *   Copyright (C) 1997 University of Chicago. 
 *   See COPYRIGHT notice in top-level directory.
 */

#include "ad_xfs.h"

#ifdef HAVE_MALLOC_H
#include <malloc.h>
#endif

/* style: allow:free:2 sig:0 */

static int ADIOI_XFS_Aligned_Mem_File_Write(ADIO_File fd, void *buf,
                          ADIO_Offset len, ADIO_Offset offset);

void ADIOI_XFS_WriteContig(ADIO_File fd, void *buf, int count, 
                     MPI_Datatype datatype, int file_ptr_type,
             ADIO_Offset offset, ADIO_Status *status, int *error_code)
{
    int err=-1, datatype_size, diff, size;
    ssize_t len;
    void *newbuf;
    static char myname[] = "ADIOI_XFS_WRITECONTIG";

    MPI_Type_size(datatype, &datatype_size);
    len = datatype_size * count;

    fd->fp_sys_posn = -1; /* set it to null, since we are using pwrite */

    if (file_ptr_type == ADIO_INDIVIDUAL) offset = fd->fp_ind;

    if (!(fd->direct_write)) {    /* direct I/O not enabled */
    err = pwrite(fd->fd_sys, buf, len, offset);
    if (err < 0) {goto leaving;}
    } else {       /* direct I/O enabled */

    /* (1) if mem_aligned && file_aligned 
                    use direct I/O to write up to correct io_size
                    use buffered I/O for remaining  */

    if (!(((long) buf) % fd->d_mem) && !(offset % fd->d_miniosz)) {
        err = ADIOI_XFS_Aligned_Mem_File_Write(fd, buf, len, offset);
        if (err < 0) {goto leaving;}

        /* (2) if !file_aligned
                    use buffered I/O to write up to file_aligned
                    At that point, if still mem_aligned, use (1)
                else copy into aligned buf and then use (1) */
    } else if (offset % fd->d_miniosz) {
        diff = fd->d_miniosz - (offset % fd->d_miniosz);
        diff = ADIOI_MIN(diff, len);
        err = pwrite(fd->fd_sys, buf, diff, offset);
        if (err < 0) {goto leaving;}

        buf = ((char *) buf) + diff;
        offset += diff;
        size = len - diff;
        if (!(((long) buf) % fd->d_mem)) {
        err = ADIOI_XFS_Aligned_Mem_File_Write(fd, buf, size, offset);
        if (err < 0) {goto leaving;}
        }
        else {
        newbuf = (void *) memalign(XFS_MEMALIGN, size);
        if (newbuf) {
            memcpy(newbuf, buf, size);
            err = ADIOI_XFS_Aligned_Mem_File_Write(fd, newbuf, size, offset);
            ADIOI_Free(newbuf);
            if (err < 0) {goto leaving;}
        } else {
            err = pwrite(fd->fd_sys, buf, size, offset);
            if (err < 0) {goto leaving;}
        }
        }
    }

        /* (3) if !mem_aligned && file_aligned
                    copy into aligned buf, then use (1)  */
    else {
        newbuf = (void *) memalign(XFS_MEMALIGN, len);
        if (newbuf) {
        memcpy(newbuf, buf, len);
        err = ADIOI_XFS_Aligned_Mem_File_Write(fd, newbuf, len, offset);
        ADIOI_Free(newbuf);
        } else {
         err = pwrite(fd->fd_sys, buf, len, offset);
        }

        if (err < 0) {goto leaving;}
    }
    }

    if (file_ptr_type == ADIO_INDIVIDUAL) fd->fp_ind += len;

#ifdef HAVE_STATUS_SET_BYTES
    if (err != -1) MPIR_Status_set_bytes(status, datatype, len);
#endif
leaving:
    if (err == -1) {
    *error_code = MPIO_Err_create_code(MPI_SUCCESS, MPIR_ERR_RECOVERABLE,
                       myname, __LINE__, MPI_ERR_IO, "**io",
                       "**io %s", strerror(errno));
    }
    else *error_code = MPI_SUCCESS;
}


static int
ADIOI_XFS_Aligned_Mem_File_Write(ADIO_File fd, void *buf, ADIO_Offset len, 
              ADIO_Offset offset)
{
    unsigned write_chunk_sz = fd->hints->fs_hints.xfs.write_chunk_sz;
    ADIO_Offset nbytes, rem, newrem, size;
    int ntimes, i;

    /* memory buffer is aligned, offset in file is aligned,
       io_size may or may not be of the right size.
       use direct I/O to write up to correct io_size,
       use buffered I/O for remaining. */

    if (!(len % fd->d_miniosz) && 
     (len >= fd->d_miniosz) && (len <= write_chunk_sz)) {
    nbytes = pwrite(fd->fd_direct, buf, len, offset);
    if (nbytes < 0) {return -1;}
    } else if (len < fd->d_miniosz) {
    nbytes = pwrite(fd->fd_sys, buf, len, offset);
    if (nbytes < 0) {return -1;}
    } else if (len > write_chunk_sz) {
    ntimes = len/(write_chunk_sz);
    rem = len - ntimes * write_chunk_sz;
    nbytes = 0;
    for (i=0; i<ntimes; i++) {
        nbytes = pwrite(fd->fd_direct, ((char *)buf) + i * write_chunk_sz,
             write_chunk_sz, offset);
        offset += write_chunk_sz;
        if (nbytes < 0) {return -1;}
    }
    if (rem) {
        if (!(rem % fd->d_miniosz)) {
        nbytes = pwrite(fd->fd_direct, 
                     ((char *)buf) + ntimes * write_chunk_sz, rem, offset);
        if (nbytes < 0) {return -1;}
        } else {
        newrem = rem % fd->d_miniosz;
        size = rem - newrem;
        if (size) {
            nbytes = pwrite(fd->fd_direct, 
                    ((char *)buf) + ntimes * write_chunk_sz, size, offset);
            offset += size;
            if (nbytes < 0) {return -1;}
        }
        nbytes = pwrite(fd->fd_sys, 
                  ((char *)buf) + ntimes * write_chunk_sz + size, newrem, offset);
        if (nbytes < 0) {return -1;}
        }
    }
    }
    else {
    rem = len % fd->d_miniosz;
    size = len - rem;
    nbytes = pwrite(fd->fd_direct, buf, size, offset);
    if (nbytes < 0) {return -1;}
    nbytes = pwrite(fd->fd_sys, (char *)buf + size, rem, offset+size);
    if (nbytes < 0) {return -1;}
    }

    return 0;
}

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