Method _write

src/client/Client.cc:12671–12983

}

int64_t Client::_write(Fh *f, int64_t offset, uint64_t size, bufferlist bl,
	               Context *onfinish, bool do_fsync, bool syncdataonly)
{
  ceph_assert(ceph_mutex_is_locked_by_me(client_lock));

  uint64_t fpos = 0;
  Inode *in = f->inode.get();
  std::unique_ptr<C_SaferCond> onuninline = nullptr;
  CWF_iofinish *cwf_iofinish = NULL;
  C_SaferCond *cond_iofinish = NULL;

  if (size < 1) { // zero bytes write is not supported by osd
    return -EINVAL;
  }

  if ( (uint64_t)(offset+size) > mdsmap->get_max_filesize() && //exceeds config
       (uint64_t)(offset+size) > in->size ) { //exceeds filesize 
      return -EFBIG;              
	}
  ldout(cct, 7) << "_write fh " << f << " size " << size << " offset " << offset << dendl;

  if (objecter->osdmap_pool_full(in->layout.pool_id)) {
    return -ENOSPC;
  }

  ceph_assert(in->snapid == CEPH_NOSNAP);

  // was Fh opened as writeable?
  if ((f->mode & CEPH_FILE_MODE_WR) == 0)
    return -EBADF;

  // use/adjust fd pos?
  if (offset < 0) {
    lock_fh_pos(f);
    /*
     * FIXME: this is racy in that we may block _after_ this point waiting for caps, and size may
     * change out from under us.
     */
    if (f->flags & O_APPEND) {
      auto r = _lseek(f, 0, SEEK_END);
      if (r < 0) {
        unlock_fh_pos(f);
        return r;
      }
    }
    offset = f->pos;
    fpos = offset+size;
    unlock_fh_pos(f);
  }

  // check quota
  uint64_t endoff = offset + size;
  if (endoff > in->size && is_quota_bytes_exceeded(in, endoff - in->size,
						   f->actor_perms)) {
    return -EDQUOT;
  }

  //bool lazy = f->mode == CEPH_FILE_MODE_LAZY;