/*
* rw_verify_area doesn't like huge counts. We limit
* them to something that fits in "int" so that others
* won't have to do range checks all the time.
*/
int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count)
{
struct inode *inode;
loff_t pos;
int retval = -EINVAL;
inode = file_inode(file);
if (unlikely((ssize_t) count < 0))
return retval;
pos = *ppos;
if (unlikely(pos < 0)) {
if (!unsigned_offsets(file))
return retval;
if (count >= -pos) /* both values are in 0..LLONG_MAX */
return -EOVERFLOW;
} else if (unlikely((loff_t) (pos + count) < 0)) {
if (!unsigned_offsets(file))
return retval;
}
if (unlikely(inode->i_flock && mandatory_lock(inode))) {
retval = locks_mandatory_area(
read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE,
inode, file, pos, count);
if (retval < 0)
return retval;
}
retval = security_file_permission(file,
read_write == READ ? MAY_READ : MAY_WRITE);
if (retval)
return retval;
return count > MAX_RW_COUNT ? MAX_RW_COUNT : count;
}
int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count)
{
struct inode *inode;
loff_t pos;
int retval = -EINVAL;
inode = file->f_path.dentry->d_inode;
if (unlikely((ssize_t) count < 0))
return retval;
pos = *ppos;
if (unlikely((pos < 0) || (loff_t) (pos + count) < 0))
return retval;
if (unlikely(inode->i_flock && mandatory_lock(inode))) {
retval = locks_mandatory_area(
read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE,
inode, file, pos, count);
if (retval < 0)
return retval;
}
retval = security_file_permission(file,
read_write == READ ? MAY_READ : MAY_WRITE);
if (retval)
return retval;
return count > MAX_RW_COUNT ? MAX_RW_COUNT : count;
}
static int clone_verify_area(struct file *file, loff_t pos, u64 len, bool write)
{
struct inode *inode = file_inode(file);
if (unlikely(pos < 0))
return -EINVAL;
if (unlikely((loff_t) (pos + len) < 0))
return -EINVAL;
if (unlikely(inode->i_flctx && mandatory_lock(inode))) {
loff_t end = len ? pos + len - 1 : OFFSET_MAX;
int retval;
retval = locks_mandatory_area(inode, file, pos, end,
write ? F_WRLCK : F_RDLCK);
if (retval < 0)
return retval;
}
return security_file_permission(file, write ? MAY_WRITE : MAY_READ);
}
/*
* Free space in a file
*
* IN: zp - znode of file to free data in.
* off - start of range
* len - end of range (0 => EOF)
* flag - current file open mode flags.
* log - TRUE if this action should be logged
*
* RETURN: 0 on success, error code on failure
*/
int
zfs_freesp(znode_t *zp, uint64_t off, uint64_t len, int flag, boolean_t log)
{
struct inode *ip = ZTOI(zp);
dmu_tx_t *tx;
zfs_sb_t *zsb = ZTOZSB(zp);
zilog_t *zilog = zsb->z_log;
uint64_t mode;
uint64_t mtime[2], ctime[2];
sa_bulk_attr_t bulk[3];
int count = 0;
int error;
if ((error = sa_lookup(zp->z_sa_hdl, SA_ZPL_MODE(zsb), &mode,
sizeof (mode))) != 0)
return (error);
if (off > zp->z_size) {
error = zfs_extend(zp, off+len);
if (error == 0 && log)
goto log;
else
return (error);
}
/*
* Check for any locks in the region to be freed.
*/
if (ip->i_flock && mandatory_lock(ip)) {
uint64_t length = (len ? len : zp->z_size - off);
if (!lock_may_write(ip, off, length))
return (SET_ERROR(EAGAIN));
}
if (len == 0) {
error = zfs_trunc(zp, off);
} else {
if ((error = zfs_free_range(zp, off, len)) == 0 &&
off + len > zp->z_size)
error = zfs_extend(zp, off+len);
}
if (error || !log)
return (error);
log:
tx = dmu_tx_create(zsb->z_os);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
zfs_sa_upgrade_txholds(tx, zp);
error = dmu_tx_assign(tx, TXG_WAIT);
if (error) {
dmu_tx_abort(tx);
return (error);
}
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zsb), NULL, mtime, 16);
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zsb), NULL, ctime, 16);
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zsb),
NULL, &zp->z_pflags, 8);
zfs_tstamp_update_setup(zp, CONTENT_MODIFIED, mtime, ctime, B_TRUE);
error = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx);
ASSERT(error == 0);
zfs_log_truncate(zilog, tx, TX_TRUNCATE, zp, off, len);
dmu_tx_commit(tx);
zfs_inode_update(zp);
return (0);
}
