/*
   Copyright (c) 2015 Red Hat, Inc. <http://www.redhat.com>
   This file is part of GlusterFS.

   This file is licensed to you under your choice of the GNU Lesser
   General Public License, version 3 or any later version (LGPLv3 or
   later), or the GNU General Public License, version 2 (GPLv2), in all
   cases as published by the Free Software Foundation.
*/
#ifndef __UPCALL_H__
#define __UPCALL_H__

#include "compat-errno.h"
#include "upcall-mem-types.h"
#include "client_t.h"
#include "upcall-messages.h"
#include "upcall-cache-invalidation.h"
#include "upcall-utils.h"

#define EXIT_IF_UPCALL_OFF(this, label) do {                       \
        if (!is_upcall_enabled(this))                              \
                goto label;                                        \
} while (0)

#define UPCALL_STACK_UNWIND(fop, frame, params ...) do {        \
        upcall_local_t *__local = NULL;                         \
        xlator_t *__xl          = NULL;                         \
        if (frame) {                                            \
                        __xl         = frame->this;             \
                        __local      = frame->local;            \
                        frame->local = NULL;                    \
        }                                                       \
        STACK_UNWIND_STRICT (fop, frame, params);               \
        upcall_local_wipe (__xl, __local);                      \
} while (0)

#define UPCALL_STACK_DESTROY(frame) do {                   \
                upcall_local_t *__local = NULL;            \
                xlator_t    *__xl    = NULL;               \
                __xl                 = frame->this;        \
                __local              = frame->local;       \
                frame->local         = NULL;               \
                STACK_DESTROY (frame->root);               \
                upcall_local_wipe (__xl, __local);         \
} while (0)

struct _upcall_private_t {
        gf_boolean_t     cache_invalidation_enabled;
        int32_t          cache_invalidation_timeout;
        struct list_head inode_ctx_list;
        gf_lock_t        inode_ctx_lk;
        gf_boolean_t     reaper_init_done;
        pthread_t        reaper_thr;
        int32_t          fini;
        dict_t          *xattrs; /* list of xattrs registered by clients
                                    for receiving invalidation */
};
typedef struct _upcall_private_t upcall_private_t;

struct _upcall_client_t {
        struct list_head client_list;
        /* strdup to store client_uid, strdup. Free it explicitly */
        char *client_uid;
        time_t access_time; /* time last accessed */
        /* the amount of time which client can cache this entry */
        uint32_t expire_time_attr;
};
typedef struct _upcall_client_t upcall_client_t;

/* Upcall entries are maintained in inode_ctx */
struct _upcall_inode_ctx_t {
        struct list_head inode_ctx_list;
        struct list_head client_list;
        pthread_mutex_t client_list_lock; /* mutex for clients list
                                             of this upcall entry */
        int destroy;
        uuid_t   gfid; /* gfid of the entry */
};
typedef struct _upcall_inode_ctx_t upcall_inode_ctx_t;

struct upcall_local {
        /* XXX: need to check if we can store
         * pointers in 'local' which may get freed
         * in future by other thread
         */
        upcall_inode_ctx_t *upcall_inode_ctx;
        inode_t   *inode;
        loc_t     rename_oldloc;
        loc_t     loc;  /* required for stat in *xattr_cbk */
        fd_t      *fd;  /* required for fstat in *xattr_cbk */
        dict_t    *xattr;
};
typedef struct upcall_local upcall_local_t;

void upcall_local_wipe (xlator_t *this, upcall_local_t *local);
upcall_local_t *upcall_local_init (call_frame_t *frame, xlator_t *this,
                                   loc_t *loc, fd_t *fd, inode_t *inode,
                                   dict_t *xattr);

upcall_client_t *add_upcall_client (call_frame_t *frame, client_t *client,
                                    upcall_inode_ctx_t *up_inode_ctx);
upcall_client_t *__add_upcall_client (call_frame_t *frame, client_t *client,
                                      upcall_inode_ctx_t *up_inode_ctx);
upcall_client_t *__get_upcall_client (call_frame_t *frame, client_t *client,
                                      upcall_inode_ctx_t *up_inode_ctx);
int __upcall_cleanup_client_entry (upcall_client_t *up_client);
int upcall_cleanup_expired_clients (xlator_t *this,
                                    upcall_inode_ctx_t *up_inode_ctx);

int __upcall_inode_ctx_set (inode_t *inode, xlator_t *this);
upcall_inode_ctx_t *__upcall_inode_ctx_get (inode_t *inode, xlator_t *this);
upcall_inode_ctx_t *upcall_inode_ctx_get (inode_t *inode, xlator_t *this);
int upcall_cleanup_inode_ctx (xlator_t *this, inode_t *inode);
void upcall_cache_forget (xlator_t *this, inode_t *inode,
                          upcall_inode_ctx_t *up_inode_ctx);

void *upcall_reaper_thread (void *data);
int upcall_reaper_thread_init (xlator_t *this);

/* Xlator options */
gf_boolean_t is_upcall_enabled (xlator_t *this);

/* Cache invalidation specific */
void upcall_cache_invalidate (call_frame_t *frame, xlator_t *this,
                              client_t *client, inode_t *inode,
                              uint32_t flags, struct iatt *stbuf,
                              struct iatt *p_stbuf,
                              struct iatt *oldp_stbuf, dict_t *xattr);
void upcall_client_cache_invalidate (xlator_t *xl, uuid_t gfid,
                                     upcall_client_t *up_client_entry,
                                     uint32_t flags, struct iatt *stbuf,
                                     struct iatt *p_stbuf,
                                     struct iatt *oldp_stbuf, dict_t *xattr);

int up_filter_unregd_xattr (dict_t *xattrs, char *xattr, data_t *v,
                            void *regd_xattrs);
#endif /* __UPCALL_H__ */