linux/fs/ceph/ioctl.c
Sage Weil 8c6e9229fc ceph: add LAZYIO ioctl to mark a file description for lazy consistency
Allow an application to mark a file descriptor for lazy file consistency
semantics, allowing buffered reads and writes when multiple clients are
accessing the same file.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-08-01 20:11:39 -07:00

185 lines
5.0 KiB
C

#include <linux/in.h>
#include "ioctl.h"
#include "super.h"
#include "ceph_debug.h"
/*
* ioctls
*/
/*
* get and set the file layout
*/
static long ceph_ioctl_get_layout(struct file *file, void __user *arg)
{
struct ceph_inode_info *ci = ceph_inode(file->f_dentry->d_inode);
struct ceph_ioctl_layout l;
int err;
err = ceph_do_getattr(file->f_dentry->d_inode, CEPH_STAT_CAP_LAYOUT);
if (!err) {
l.stripe_unit = ceph_file_layout_su(ci->i_layout);
l.stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
l.object_size = ceph_file_layout_object_size(ci->i_layout);
l.data_pool = le32_to_cpu(ci->i_layout.fl_pg_pool);
l.preferred_osd =
(s32)le32_to_cpu(ci->i_layout.fl_pg_preferred);
if (copy_to_user(arg, &l, sizeof(l)))
return -EFAULT;
}
return err;
}
static long ceph_ioctl_set_layout(struct file *file, void __user *arg)
{
struct inode *inode = file->f_dentry->d_inode;
struct inode *parent_inode = file->f_dentry->d_parent->d_inode;
struct ceph_mds_client *mdsc = &ceph_sb_to_client(inode->i_sb)->mdsc;
struct ceph_mds_request *req;
struct ceph_ioctl_layout l;
int err, i;
/* copy and validate */
if (copy_from_user(&l, arg, sizeof(l)))
return -EFAULT;
if ((l.object_size & ~PAGE_MASK) ||
(l.stripe_unit & ~PAGE_MASK) ||
!l.stripe_unit ||
(l.object_size &&
(unsigned)l.object_size % (unsigned)l.stripe_unit))
return -EINVAL;
/* make sure it's a valid data pool */
if (l.data_pool > 0) {
mutex_lock(&mdsc->mutex);
err = -EINVAL;
for (i = 0; i < mdsc->mdsmap->m_num_data_pg_pools; i++)
if (mdsc->mdsmap->m_data_pg_pools[i] == l.data_pool) {
err = 0;
break;
}
mutex_unlock(&mdsc->mutex);
if (err)
return err;
}
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETLAYOUT,
USE_AUTH_MDS);
if (IS_ERR(req))
return PTR_ERR(req);
req->r_inode = igrab(inode);
req->r_inode_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_EXCL;
req->r_args.setlayout.layout.fl_stripe_unit =
cpu_to_le32(l.stripe_unit);
req->r_args.setlayout.layout.fl_stripe_count =
cpu_to_le32(l.stripe_count);
req->r_args.setlayout.layout.fl_object_size =
cpu_to_le32(l.object_size);
req->r_args.setlayout.layout.fl_pg_pool = cpu_to_le32(l.data_pool);
req->r_args.setlayout.layout.fl_pg_preferred =
cpu_to_le32(l.preferred_osd);
err = ceph_mdsc_do_request(mdsc, parent_inode, req);
ceph_mdsc_put_request(req);
return err;
}
/*
* 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->f_dentry->d_inode;
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_osd_client *osdc = &ceph_sb_to_client(inode->i_sb)->osdc;
u64 len = 1, olen;
u64 tmp;
struct ceph_object_layout ol;
struct ceph_pg pgid;
/* copy and validate */
if (copy_from_user(&dl, arg, sizeof(dl)))
return -EFAULT;
down_read(&osdc->map_sem);
ceph_calc_file_object_mapping(&ci->i_layout, dl.file_offset, &len,
&dl.object_no, &dl.object_offset, &olen);
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;
}
static long ceph_ioctl_lazyio(struct file *file)
{
struct ceph_file_info *fi = file->private_data;
struct inode *inode = file->f_dentry->d_inode;
struct ceph_inode_info *ci = ceph_inode(inode);
if ((fi->fmode & CEPH_FILE_MODE_LAZY) == 0) {
spin_lock(&inode->i_lock);
ci->i_nr_by_mode[fi->fmode]--;
fi->fmode |= CEPH_FILE_MODE_LAZY;
ci->i_nr_by_mode[fi->fmode]++;
spin_unlock(&inode->i_lock);
dout("ioctl_layzio: file %p marked lazy\n", file);
ceph_check_caps(ci, 0, NULL);
} else {
dout("ioctl_layzio: file %p already lazy\n", file);
}
return 0;
}
long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
dout("ioctl file %p cmd %u arg %lu\n", file, cmd, arg);
switch (cmd) {
case CEPH_IOC_GET_LAYOUT:
return ceph_ioctl_get_layout(file, (void __user *)arg);
case CEPH_IOC_SET_LAYOUT:
return ceph_ioctl_set_layout(file, (void __user *)arg);
case CEPH_IOC_GET_DATALOC:
return ceph_ioctl_get_dataloc(file, (void __user *)arg);
case CEPH_IOC_LAZYIO:
return ceph_ioctl_lazyio(file);
}
return -ENOTTY;
}