1 files changed, 193 insertions, 0 deletions
diff --git a/libglusterfs/src/glusterfs/iobuf.h b/libglusterfs/src/glusterfs/iobuf.h
new file mode 100644
index 00000000000..6de0f13ae36
--- /dev/null
+++ b/libglusterfs/src/glusterfs/iobuf.h
@@ -0,0 +1,193 @@
+/*
+  Copyright (c) 2008-2012 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 _IOBUF_H_
+#define _IOBUF_H_
+
+#include "glusterfs/list.h"
+#include "glusterfs/common-utils.h"
+#include <pthread.h>
+#include <sys/mman.h>
+#include <sys/uio.h>
+
+#define GF_VARIABLE_IOBUF_COUNT 32
+
+#define GF_RDMA_DEVICE_COUNT 8
+
+/* Lets try to define the new anonymous mapping
+ * flag, in case the system is still using the
+ * now deprecated MAP_ANON flag.
+ *
+ * Also, this should ideally be in a centralized/common
+ * header which can be used by other source files also.
+ */
+#ifndef MAP_ANONYMOUS
+#define MAP_ANONYMOUS MAP_ANON
+#endif
+
+#define GF_ALIGN_BUF(ptr, bound)                                               \
+    ((void *)((unsigned long)(ptr + bound - 1) & (unsigned long)(~(bound - 1))))
+
+#define GF_IOBUF_ALIGN_SIZE 512
+
+/* one allocatable unit for the consumers of the IOBUF API */
+/* each unit hosts @page_size bytes of memory */
+struct iobuf;
+
+/* one region of memory mapped from the operating system */
+/* each region MMAPs @arena_size bytes of memory */
+/* each arena hosts @arena_size / @page_size IOBUFs */
+struct iobuf_arena;
+
+/* expandable and contractable pool of memory, internally broken into arenas */
+struct iobuf_pool;
+
+struct iobuf_init_config {
+    size_t pagesize;
+    int32_t num_pages;
+};
+
+struct iobuf {
+    union {
+        struct list_head list;
+        struct {
+            struct iobuf *next;
+            struct iobuf *prev;
+        };
+    };
+    struct iobuf_arena *iobuf_arena;
+
+    gf_lock_t lock;  /* for ->ptr and ->ref */
+    gf_atomic_t ref; /* 0 == passive, >0 == active */
+
+    void *ptr; /* usable memory region by the consumer */
+
+    void *free_ptr; /* in case of stdalloc, this is the
+                       one to be freed */
+};
+
+struct iobuf_arena {
+    union {
+        struct list_head list;
+        struct {
+            struct iobuf_arena *next;
+            struct iobuf_arena *prev;
+        };
+    };
+
+    struct list_head all_list;
+    size_t page_size; /* size of all iobufs in this arena */
+    size_t arena_size;
+    /* this is equal to rounded_size * num_iobufs.
+       (rounded_size comes with gf_iobuf_get_pagesize().) */
+    size_t page_count;
+
+    struct iobuf_pool *iobuf_pool;
+
+    void *mem_base;
+    struct iobuf *iobufs; /* allocated iobufs list */
+
+    int active_cnt;
+    struct iobuf active; /* head node iobuf
+                            (unused by itself) */
+    int passive_cnt;
+    struct iobuf passive; /* head node iobuf
+                             (unused by itself) */
+    uint64_t alloc_cnt;   /* total allocs in this pool */
+    int max_active;       /* max active buffers at a given time */
+};
+
+struct iobuf_pool {
+    pthread_mutex_t mutex;
+    size_t arena_size;        /* size of memory region in
+                                 arena */
+    size_t default_page_size; /* default size of iobuf */
+
+    int arena_cnt;
+    struct list_head all_arenas;
+    struct list_head arenas[GF_VARIABLE_IOBUF_COUNT];
+    /* array of arenas. Each element of the array is a list of arenas
+       holding iobufs of particular page_size */
+
+    struct list_head filled[GF_VARIABLE_IOBUF_COUNT];
+    /* array of arenas without free iobufs */
+
+    struct list_head purge[GF_VARIABLE_IOBUF_COUNT];
+    /* array of of arenas which can be purged */
+
+    uint64_t request_misses; /* mostly the requests for higher
+                               value of iobufs */
+    int rdma_device_count;
+    struct list_head *mr_list[GF_RDMA_DEVICE_COUNT];
+    void *device[GF_RDMA_DEVICE_COUNT];
+    int (*rdma_registration)(void **, void *);
+    int (*rdma_deregistration)(struct list_head **, struct iobuf_arena *);
+};
+
+struct iobuf_pool *
+iobuf_pool_new(void);
+void
+iobuf_pool_destroy(struct iobuf_pool *iobuf_pool);
+struct iobuf *
+iobuf_get(struct iobuf_pool *iobuf_pool);
+void
+iobuf_unref(struct iobuf *iobuf);
+struct iobuf *
+iobuf_ref(struct iobuf *iobuf);
+void
+iobuf_pool_destroy(struct iobuf_pool *iobuf_pool);
+void
+iobuf_to_iovec(struct iobuf *iob, struct iovec *iov);
+
+#define iobuf_ptr(iob) ((iob)->ptr)
+#define iobpool_default_pagesize(iobpool) ((iobpool)->default_page_size)
+#define iobuf_pagesize(iob) (iob->iobuf_arena->page_size)
+
+struct iobref {
+    gf_lock_t lock;
+    gf_atomic_t ref;
+    struct iobuf **iobrefs;
+    int allocated;
+    int used;
+};
+
+struct iobref *
+iobref_new(void);
+struct iobref *
+iobref_ref(struct iobref *iobref);
+void
+iobref_unref(struct iobref *iobref);
+int
+iobref_add(struct iobref *iobref, struct iobuf *iobuf);
+int
+iobref_merge(struct iobref *to, struct iobref *from);
+void
+iobref_clear(struct iobref *iobref);
+
+size_t
+iobuf_size(struct iobuf *iobuf);
+size_t
+iobref_size(struct iobref *iobref);
+void
+iobuf_stats_dump(struct iobuf_pool *iobuf_pool);
+
+struct iobuf *
+iobuf_get2(struct iobuf_pool *iobuf_pool, size_t page_size);
+
+struct iobuf *
+iobuf_get_page_aligned(struct iobuf_pool *iobuf_pool, size_t page_size,
+                       size_t align_size);
+
+int
+iobuf_copy(struct iobuf_pool *iobuf_pool, const struct iovec *iovec_src,
+           int iovcnt, struct iobref **iobref, struct iobuf **iobuf,
+           struct iovec *iov_dst);
+
+#endif /* !_IOBUF_H_ */