Here are five possible code completions for the given function:

**Completion 1: Basic Attribute Encoding**

```c
/* Initialize attribute bitmap */
bitmap_zero(attr_bitmap, ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops));

/* Set attribute mask based on bmval */
if (bmval) {
    for (int i = 0; i < ARRAY_SIZE(attrmask); i++) {
        attrmask[i] = bmval[i];
    }
} else {
    /* Default attribute mask */
    attrmask[0] = FATTR4_SUPPORTED_ATTRS;
    attrmask[1] = 0;
    attrmask[2] = 0;
}

/* Encode attributes */
for (int i = 0; i < ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops); i++) {
    if (test_bit(i, attr_bitmap)) {
        nfsd4_enc_fattr4_encode_ops[i](rqstp, xdr, fhp, exp, dentry, &args);
    }
}

/* Calculate attribute length */
attrlen_offset = xdr->buf->len - starting_len;
attrlen_p = xdr->buf->data + starting_len;
*attrlen_p = cpu_to_be32(attrlen_offset);

/* Return status */
status = nfs_ok;
return status;
```

**Completion 2: With Error Handling**

```c
/* Initialize attribute bitmap */
bitmap_zero(attr_bitmap, ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops));

/* Set attribute mask based on bmval */
if (bmval) {
    for (int i = 0; i < ARRAY_SIZE(attrmask); i++) {
        attrmask[i] = bmval[i];
    }
} else {
    /* Default attribute mask */
    attrmask[0] = FATTR4_SUPPORTED_ATTRS;
    attrmask[1] = 0;
    attrmask[2] = 0;
}

/* Encode attributes */
for (int i = 0; i < ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops); i++) {
    if (test_bit(i, attr_bitmap)) {
        err = nfsd4_enc_fattr4_encode_ops[i](rqstp, xdr, fhp, exp, dentry, &args);
        if (err) {
            status = nfserr_attrnotsupp;
            return status;
        }
    }
}

/* Calculate attribute length */
attrlen_offset = xdr->buf->len - starting_len;
attrlen_p = xdr->buf->data + starting_len;
*attrlen_p = cpu_to_be32(attrlen_offset);

/* Return status */
status = nfs_ok;
return status;
```

**Completion 3: With File Size and Modification Time**

```c
/* Initialize attribute bitmap */
bitmap_zero(attr_bitmap, ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops));

/* Set attribute mask based on bmval */
if (bmval) {
    for (int i = 0; i < ARRAY_SIZE(attrmask); i++) {
        attrmask[i] = bmval[i];
    }
} else {
    /* Default attribute mask */
    attrmask[0] = FATTR4_SUPPORTED_ATTRS;
    attrmask[1] = 0;
    attrmask[2] = 0;
}

/* Get file size and modification time */
size = i_size_read(dentry->d_inode);
file_modified = dentry->d_inode->i_mtime.tv_sec != 0;

/* Encode attributes */
for (int i = 0; i < ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops); i++) {
    if (test_bit(i, attr_bitmap)) {
        nfsd4_enc_fattr4_encode_ops[i](rqstp, xdr, fhp, exp, dentry, &args);
    }
}

/* Encode file size and modification time */
if (file_modified) {
    nfsd4_enc_fattr4_encode_ops[FATTR4_TIME_MODIFY](rqstp, xdr, fhp, exp, dentry, &args);
}
if (size > 0) {
    nfsd4_enc_fattr4_encode_ops[FATTR4_SIZE](rqstp, xdr, fhp, exp, dentry, &args);
}

/* Calculate attribute length */
attrlen_offset = xdr->buf->len - starting_len;
attrlen_p = xdr->buf->data + starting_len;
*attrlen_p = cpu_to_be32(attrlen_offset);

/* Return status */
status = nfs_ok;
return status;
```

**Completion 4: With Cross-Mount Point Handling**

```c
/* Initialize attribute bitmap */
bitmap_zero(attr_bitmap, ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops));

/* Set attribute mask based on bmval */
if (bmval) {
    for (int i = 0; i < ARRAY_SIZE(attrmask); i++) {
        attrmask[i] = bmval[i];
    }
} else {
    /* Default attribute mask */
    attrmask[0] = FATTR4_SUPPORTED_ATTRS;
    attrmask[1] = 0;
    attrmask[2] = 0;
}

/* Handle cross-mount point */
if (ignore_crossmnt) {
    tempfh = svc_fh_get(exp, dentry);
    if (!tempfh) {
        status = nfserr_noent;
        return status;
    }
    fhp = tempfh;
}

/* Encode attributes */
for (int i = 0; i < ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops); i++) {
    if (test_bit(i, attr_bitmap)) {
        nfsd4_enc_fattr4_encode_ops[i](rqstp, xdr, fhp, exp, dentry, &args);
    }
}

/* Calculate attribute length */
attrlen_offset = xdr->buf->len - starting_len;
attrlen_p = xdr->buf->data + starting_len;
*attrlen_p = cpu_to_be32(attrlen_offset);

/* Release temporary file handle */
if (tempfh) {
    svc_fh_put(tempfh);
}

/* Return status */
status = nfs_ok;
return status;
```

**Completion 5: With Minor Version Handling**

```c
/* Initialize attribute bitmap */
bitmap_zero(attr_bitmap, ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops));

/* Set attribute mask based on bmval */
if (bmval) {
    for (int i = 0; i < ARRAY_SIZE(attrmask); i++) {
        attrmask[i] = bmval[i];
    }
} else {
    /* Default attribute mask */
    attrmask[0] = FATTR4_SUPPORTED_ATTRS;
    attrmask[1] = 0;
    attrmask[2] = 0;
}

/* Handle minor version */
if (minorversion >= 2) {
    /* Encode additional attributes for minor version 2 and above */
    nfsd4_enc_fattr4_encode_ops[FATTR4_CHANGE](rqstp, xdr, fhp, exp, dentry, &args);
}

/* Encode attributes */
for (int i = 0; i < ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops); i++) {
    if (test_bit(i, attr_bitmap)) {
        nfsd4_enc_fattr4_encode_ops[i](rqstp, xdr, fhp, exp, dentry, &args);
    }
}

/* Calculate attribute length */
attrlen_offset = xdr->buf->len - starting_len;
attrlen_p = xdr->buf->data + starting_len;
*attrlen_p = cpu_to_be32(attrlen_offset);

/* Return status */
status = nfs_ok;
return status;
```