/*
* calculate the mapping of a file extent onto an object, and fill out the
* request accordingly. shorten extent as necessary if it crosses an
* object boundary.
*
* fill osd op in request message.
*/
static void calc_layout(struct ceph_osd_client *osdc,
struct ceph_vino vino, struct ceph_file_layout *layout,
u64 off, u64 *plen,
struct ceph_osd_request *req)
{
struct ceph_osd_request_head *reqhead = req->r_request->front.iov_base;
struct ceph_osd_op *op = (void *)(reqhead + 1);
u64 orig_len = *plen;
u64 objoff, objlen; /* extent in object */
u64 bno;
reqhead->snapid = cpu_to_le64(vino.snap);
/* object extent? */
ceph_calc_file_object_mapping(layout, off, plen, &bno,
&objoff, &objlen);
if (*plen < orig_len)
dout(" skipping last %llu, final file extent %llu~%llu\n",
orig_len - *plen, off, *plen);
sprintf(req->r_oid, "%llx.%08llx", vino.ino, bno);
req->r_oid_len = strlen(req->r_oid);
op->extent.offset = cpu_to_le64(objoff);
op->extent.length = cpu_to_le64(objlen);
req->r_num_pages = calc_pages_for(off, *plen);
dout("calc_layout %s (%d) %llu~%llu (%d pages)\n",
req->r_oid, req->r_oid_len, objoff, objlen, req->r_num_pages);
}
void ceph_calc_raw_layout(struct ceph_osd_client *osdc,
struct ceph_file_layout *layout,
u64 snapid,
u64 off, u64 *plen, u64 *bno,
struct ceph_osd_request *req,
struct ceph_osd_req_op *op)
{
struct ceph_osd_request_head *reqhead = req->r_request->front.iov_base;
u64 orig_len = *plen;
u64 objoff, objlen; /* extent in object */
reqhead->snapid = cpu_to_le64(snapid);
/* object extent? */
ceph_calc_file_object_mapping(layout, off, plen, bno,
&objoff, &objlen);
if (*plen < orig_len)
dout(" skipping last %llu, final file extent %llu~%llu\n",
orig_len - *plen, off, *plen);
if (op_has_extent(op->op)) {
op->extent.offset = objoff;
op->extent.length = objlen;
}
req->r_num_pages = calc_pages_for(off, *plen);
req->r_page_alignment = off & ~PAGE_MASK;
if (op->op == CEPH_OSD_OP_WRITE)
op->payload_len = *plen;
dout("calc_layout bno=%llx %llu~%llu (%d pages)\n",
*bno, objoff, objlen, req->r_num_pages);
}
/*
* Return object name, size/offset information, and location (OSD
* number, network address) for a given file offset.
*/
static long ceph_ioctl_get_dataloc(struct file *file, void __user *arg)
{
struct ceph_ioctl_dataloc dl;
struct inode *inode = file_inode(file);
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_osd_client *osdc =
&ceph_sb_to_client(inode->i_sb)->client->osdc;
u64 len = 1, olen;
u64 tmp;
struct ceph_object_layout ol;
struct ceph_pg pgid;
int r;
/* copy and validate */
if (copy_from_user(&dl, arg, sizeof(dl)))
return -EFAULT;
down_read(&osdc->map_sem);
r = ceph_calc_file_object_mapping(&ci->i_layout, dl.file_offset, &len,
&dl.object_no, &dl.object_offset,
&olen);
if (r < 0)
return -EIO;
dl.file_offset -= dl.object_offset;
dl.object_size = ceph_file_layout_object_size(ci->i_layout);
dl.block_size = ceph_file_layout_su(ci->i_layout);
/* block_offset = object_offset % block_size */
tmp = dl.object_offset;
dl.block_offset = do_div(tmp, dl.block_size);
snprintf(dl.object_name, sizeof(dl.object_name), "%llx.%08llx",
ceph_ino(inode), dl.object_no);
ceph_calc_object_layout(&ol, dl.object_name, &ci->i_layout,
osdc->osdmap);
pgid = ol.ol_pgid;
dl.osd = ceph_calc_pg_primary(osdc->osdmap, pgid);
if (dl.osd >= 0) {
struct ceph_entity_addr *a =
ceph_osd_addr(osdc->osdmap, dl.osd);
if (a)
memcpy(&dl.osd_addr, &a->in_addr, sizeof(dl.osd_addr));
} else {
memset(&dl.osd_addr, 0, sizeof(dl.osd_addr));
}
up_read(&osdc->map_sem);
/* send result back to user */
if (copy_to_user(arg, &dl, sizeof(dl)))
return -EFAULT;
return 0;
}
