Move to kernel style SPDX license identifiers
[lttng-ust.git] / libringbuffer / ring_buffer_backend.c
index b65105f3a92afdfc8eceab615b73708bb045307e..b50c2f3c406405000d8a830af1d19bfe48622e7d 100644 (file)
@@ -1,27 +1,17 @@
 /*
- * ring_buffer_backend.c
+ * SPDX-License-Identifier: LGPL-2.1-only
  *
  * Copyright (C) 2005-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; only
- * version 2.1 of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#define _GNU_SOURCE
+#define _LGPL_SOURCE
+#include <stddef.h>
+#include <stdint.h>
+#include <unistd.h>
 #include <urcu/arch.h>
 #include <limits.h>
 
+#include <lttng/align.h>
 #include <lttng/ringbuffer-config.h>
 #include "vatomic.h"
 #include "backend.h"
@@ -45,10 +35,15 @@ int lib_ring_buffer_backend_allocate(const struct lttng_ust_lib_ring_buffer_conf
                                     struct lttng_ust_shm_handle *handle,
                                     struct shm_object *shmobj)
 {
-       struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
+       struct channel_backend *chanb;
        unsigned long subbuf_size, mmap_offset = 0;
        unsigned long num_subbuf_alloc;
        unsigned long i;
+       long page_size;
+
+       chanb = &shmp(handle, bufb->chan)->backend;
+       if (!chanb)
+               return -EINVAL;
 
        subbuf_size = chanb->subbuf_size;
        num_subbuf_alloc = num_subbuf;
@@ -56,6 +51,11 @@ int lib_ring_buffer_backend_allocate(const struct lttng_ust_lib_ring_buffer_conf
        if (extra_reader_sb)
                num_subbuf_alloc++;
 
+       page_size = LTTNG_UST_PAGE_SIZE;
+       if (page_size <= 0) {
+               goto page_size_error;
+       }
+
        align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer_backend_pages_shmp));
        set_shmp(bufb->array, zalloc_shm(shmobj,
                        sizeof(struct lttng_ust_lib_ring_buffer_backend_pages_shmp) * num_subbuf_alloc));
@@ -64,9 +64,9 @@ int lib_ring_buffer_backend_allocate(const struct lttng_ust_lib_ring_buffer_conf
 
        /*
         * This is the largest element (the buffer pages) which needs to
-        * be aligned on PAGE_SIZE.
+        * be aligned on page size.
         */
-       align_shm(shmobj, PAGE_SIZE);
+       align_shm(shmobj, page_size);
        set_shmp(bufb->memory_map, zalloc_shm(shmobj,
                        subbuf_size * num_subbuf_alloc));
        if (caa_unlikely(!shmp(handle, bufb->memory_map)))
@@ -90,8 +90,14 @@ int lib_ring_buffer_backend_allocate(const struct lttng_ust_lib_ring_buffer_conf
        if (caa_unlikely(!shmp(handle, bufb->buf_wsb)))
                goto free_array;
 
-       for (i = 0; i < num_subbuf; i++)
-               shmp_index(handle, bufb->buf_wsb, i)->id = subbuffer_id(config, 0, 1, i);
+       for (i = 0; i < num_subbuf; i++) {
+               struct lttng_ust_lib_ring_buffer_backend_subbuffer *sb;
+
+               sb = shmp_index(handle, bufb->buf_wsb, i);
+               if (!sb)
+                       goto free_array;
+               sb->id = subbuffer_id(config, 0, 1, i);
+       }
 
        /* Assign read-side subbuffer table */
        if (extra_reader_sb)
@@ -100,28 +106,46 @@ int lib_ring_buffer_backend_allocate(const struct lttng_ust_lib_ring_buffer_conf
        else
                bufb->buf_rsb.id = subbuffer_id(config, 0, 1, 0);
 
+       /* Allocate subbuffer packet counter table */
+       align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer_backend_counts));
+       set_shmp(bufb->buf_cnt, zalloc_shm(shmobj,
+                               sizeof(struct lttng_ust_lib_ring_buffer_backend_counts)
+                               * num_subbuf));
+       if (caa_unlikely(!shmp(handle, bufb->buf_cnt)))
+               goto free_wsb;
+
        /* Assign pages to page index */
        for (i = 0; i < num_subbuf_alloc; i++) {
+               struct lttng_ust_lib_ring_buffer_backend_pages_shmp *sbp;
+               struct lttng_ust_lib_ring_buffer_backend_pages *pages;
                struct shm_ref ref;
 
                ref.index = bufb->memory_map._ref.index;
                ref.offset = bufb->memory_map._ref.offset;
                ref.offset += i * subbuf_size;
 
-               set_shmp(shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->p,
-                        ref);
+               sbp = shmp_index(handle, bufb->array, i);
+               if (!sbp)
+                       goto free_array;
+               pages = shmp(handle, sbp->shmp);
+               if (!pages)
+                       goto free_array;
+               set_shmp(pages->p, ref);
                if (config->output == RING_BUFFER_MMAP) {
-                       shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->mmap_offset = mmap_offset;
+                       pages->mmap_offset = mmap_offset;
                        mmap_offset += subbuf_size;
                }
        }
        return 0;
 
+free_wsb:
+       /* bufb->buf_wsb will be freed by shm teardown */
 free_array:
        /* bufb->array[i] will be freed by shm teardown */
 memory_map_error:
        /* bufb->array will be freed by shm teardown */
 array_error:
+page_size_error:
        return -ENOMEM;
 }
 
@@ -144,17 +168,28 @@ int lib_ring_buffer_backend_create(struct lttng_ust_lib_ring_buffer_backend *buf
 void lib_ring_buffer_backend_reset(struct lttng_ust_lib_ring_buffer_backend *bufb,
                                   struct lttng_ust_shm_handle *handle)
 {
-       struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
-       const struct lttng_ust_lib_ring_buffer_config *config = &chanb->config;
+       struct channel_backend *chanb;
+       const struct lttng_ust_lib_ring_buffer_config *config;
        unsigned long num_subbuf_alloc;
        unsigned int i;
 
+       chanb = &shmp(handle, bufb->chan)->backend;
+       if (!chanb)
+               return;
+       config = &chanb->config;
+
        num_subbuf_alloc = chanb->num_subbuf;
        if (chanb->extra_reader_sb)
                num_subbuf_alloc++;
 
-       for (i = 0; i < chanb->num_subbuf; i++)
-               shmp_index(handle, bufb->buf_wsb, i)->id = subbuffer_id(config, 0, 1, i);
+       for (i = 0; i < chanb->num_subbuf; i++) {
+               struct lttng_ust_lib_ring_buffer_backend_subbuffer *sb;
+
+               sb = shmp_index(handle, bufb->buf_wsb, i);
+               if (!sb)
+                       return;
+               sb->id = subbuffer_id(config, 0, 1, i);
+       }
        if (chanb->extra_reader_sb)
                bufb->buf_rsb.id = subbuffer_id(config, 0, 1,
                                                num_subbuf_alloc - 1);
@@ -162,10 +197,19 @@ void lib_ring_buffer_backend_reset(struct lttng_ust_lib_ring_buffer_backend *buf
                bufb->buf_rsb.id = subbuffer_id(config, 0, 1, 0);
 
        for (i = 0; i < num_subbuf_alloc; i++) {
+               struct lttng_ust_lib_ring_buffer_backend_pages_shmp *sbp;
+               struct lttng_ust_lib_ring_buffer_backend_pages *pages;
+
+               sbp = shmp_index(handle, bufb->array, i);
+               if (!sbp)
+                       return;
+               pages = shmp(handle, sbp->shmp);
+               if (!pages)
+                       return;
                /* Don't reset mmap_offset */
-               v_set(config, &shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->records_commit, 0);
-               v_set(config, &shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->records_unread, 0);
-               shmp(handle, shmp_index(handle, bufb->array, i)->shmp)->data_size = 0;
+               v_set(config, &pages->records_commit, 0);
+               v_set(config, &pages->records_unread, 0);
+               pages->data_size = 0;
                /* Don't reset backend page and virt addresses */
        }
        /* Don't reset num_pages_per_subbuf, cpu, allocated */
@@ -195,7 +239,7 @@ void channel_backend_reset(struct channel_backend *chanb)
  * @name: channel name
  * @config: client ring buffer configuration
  * @parent: dentry of parent directory, %NULL for root directory
- * @subbuf_size: size of sub-buffers (> PAGE_SIZE, power of 2)
+ * @subbuf_size: size of sub-buffers (> page size, power of 2)
  * @num_subbuf: number of sub-buffers (power of 2)
  * @lttng_ust_shm_handle: shared memory handle
  * @stream_fds: stream file descriptors.
@@ -219,12 +263,17 @@ int channel_backend_init(struct channel_backend *chanb,
        unsigned int i;
        int ret;
        size_t shmsize = 0, num_subbuf_alloc;
+       long page_size;
 
        if (!name)
                return -EPERM;
 
+       page_size = LTTNG_UST_PAGE_SIZE;
+       if (page_size <= 0) {
+               return -ENOMEM;
+       }
        /* Check that the subbuffer size is larger than a page. */
-       if (subbuf_size < PAGE_SIZE)
+       if (subbuf_size < page_size)
                return -EINVAL;
 
        /*
@@ -259,25 +308,29 @@ int channel_backend_init(struct channel_backend *chanb,
        memcpy(&chanb->config, config, sizeof(*config));
 
        /* Per-cpu buffer size: control (prior to backend) */
-       shmsize = offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer));
+       shmsize = lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer));
        shmsize += sizeof(struct lttng_ust_lib_ring_buffer);
+       shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct commit_counters_hot));
+       shmsize += sizeof(struct commit_counters_hot) * num_subbuf;
+       shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct commit_counters_cold));
+       shmsize += sizeof(struct commit_counters_cold) * num_subbuf;
+       /* Sampled timestamp end */
+       shmsize += lttng_ust_offset_align(shmsize, __alignof__(uint64_t));
+       shmsize += sizeof(uint64_t) * num_subbuf;
 
        /* Per-cpu buffer size: backend */
        /* num_subbuf + 1 is the worse case */
        num_subbuf_alloc = num_subbuf + 1;
-       shmsize += offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_pages_shmp));
+       shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_pages_shmp));
        shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_pages_shmp) * num_subbuf_alloc;
-       shmsize += offset_align(shmsize, PAGE_SIZE);
+       shmsize += lttng_ust_offset_align(shmsize, page_size);
        shmsize += subbuf_size * num_subbuf_alloc;
-       shmsize += offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_pages));
+       shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_pages));
        shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_pages) * num_subbuf_alloc;
-       shmsize += offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_subbuffer));
+       shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_subbuffer));
        shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_subbuffer) * num_subbuf;
-       /* Per-cpu buffer size: control (after backend) */
-       shmsize += offset_align(shmsize, __alignof__(struct commit_counters_hot));
-       shmsize += sizeof(struct commit_counters_hot) * num_subbuf;
-       shmsize += offset_align(shmsize, __alignof__(struct commit_counters_cold));
-       shmsize += sizeof(struct commit_counters_cold) * num_subbuf;
+       shmsize += lttng_ust_offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_counts));
+       shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_counts) * num_subbuf;
 
        if (config->alloc == RING_BUFFER_ALLOC_PER_CPU) {
                struct lttng_ust_lib_ring_buffer *buf;
@@ -288,7 +341,7 @@ int channel_backend_init(struct channel_backend *chanb,
                        struct shm_object *shmobj;
 
                        shmobj = shm_object_table_alloc(handle->table, shmsize,
-                                       SHM_OBJECT_SHM, stream_fds[i]);
+                                       SHM_OBJECT_SHM, stream_fds[i], i);
                        if (!shmobj)
                                goto end;
                        align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer));
@@ -307,7 +360,7 @@ int channel_backend_init(struct channel_backend *chanb,
                struct lttng_ust_lib_ring_buffer *buf;
 
                shmobj = shm_object_table_alloc(handle->table, shmsize,
-                                       SHM_OBJECT_SHM, stream_fds[0]);
+                                       SHM_OBJECT_SHM, stream_fds[0], -1);
                if (!shmobj)
                        goto end;
                align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer));
@@ -356,12 +409,18 @@ void channel_backend_free(struct channel_backend *chanb,
 size_t lib_ring_buffer_read(struct lttng_ust_lib_ring_buffer_backend *bufb, size_t offset,
                            void *dest, size_t len, struct lttng_ust_shm_handle *handle)
 {
-       struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
-       const struct lttng_ust_lib_ring_buffer_config *config = &chanb->config;
+       struct channel_backend *chanb;
+       const struct lttng_ust_lib_ring_buffer_config *config;
        ssize_t orig_len;
        struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
+       struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
        unsigned long sb_bindex, id;
+       void *src;
 
+       chanb = &shmp(handle, bufb->chan)->backend;
+       if (!chanb)
+               return 0;
+       config = &chanb->config;
        orig_len = len;
        offset &= chanb->buf_size - 1;
 
@@ -370,6 +429,8 @@ size_t lib_ring_buffer_read(struct lttng_ust_lib_ring_buffer_backend *bufb, size
        id = bufb->buf_rsb.id;
        sb_bindex = subbuffer_id_get_index(config, id);
        rpages = shmp_index(handle, bufb->array, sb_bindex);
+       if (!rpages)
+               return 0;
        /*
         * Underlying layer should never ask for reads across
         * subbuffers.
@@ -377,7 +438,13 @@ size_t lib_ring_buffer_read(struct lttng_ust_lib_ring_buffer_backend *bufb, size
        CHAN_WARN_ON(chanb, offset >= chanb->buf_size);
        CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
                     && subbuffer_id_is_noref(config, id));
-       memcpy(dest, shmp_index(handle, shmp(handle, rpages->shmp)->p, offset & (chanb->subbuf_size - 1)), len);
+       backend_pages = shmp(handle, rpages->shmp);
+       if (!backend_pages)
+               return 0;
+       src = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+       if (caa_unlikely(!src))
+               return 0;
+       memcpy(dest, src, len);
        return orig_len;
 }
 
@@ -395,13 +462,18 @@ size_t lib_ring_buffer_read(struct lttng_ust_lib_ring_buffer_backend *bufb, size
 int lib_ring_buffer_read_cstr(struct lttng_ust_lib_ring_buffer_backend *bufb, size_t offset,
                              void *dest, size_t len, struct lttng_ust_shm_handle *handle)
 {
-       struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
-       const struct lttng_ust_lib_ring_buffer_config *config = &chanb->config;
+       struct channel_backend *chanb;
+       const struct lttng_ust_lib_ring_buffer_config *config;
        ssize_t string_len, orig_offset;
        char *str;
        struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
+       struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
        unsigned long sb_bindex, id;
 
+       chanb = &shmp(handle, bufb->chan)->backend;
+       if (!chanb)
+               return -EINVAL;
+       config = &chanb->config;
        if (caa_unlikely(!len))
                return -EINVAL;
        offset &= chanb->buf_size - 1;
@@ -409,6 +481,8 @@ int lib_ring_buffer_read_cstr(struct lttng_ust_lib_ring_buffer_backend *bufb, si
        id = bufb->buf_rsb.id;
        sb_bindex = subbuffer_id_get_index(config, id);
        rpages = shmp_index(handle, bufb->array, sb_bindex);
+       if (!rpages)
+               return -EINVAL;
        /*
         * Underlying layer should never ask for reads across
         * subbuffers.
@@ -416,7 +490,12 @@ int lib_ring_buffer_read_cstr(struct lttng_ust_lib_ring_buffer_backend *bufb, si
        CHAN_WARN_ON(chanb, offset >= chanb->buf_size);
        CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
                     && subbuffer_id_is_noref(config, id));
-       str = shmp_index(handle, shmp(handle, rpages->shmp)->p, offset & (chanb->subbuf_size - 1));
+       backend_pages = shmp(handle, rpages->shmp);
+       if (!backend_pages)
+               return -EINVAL;
+       str = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+       if (caa_unlikely(!str))
+               return -EINVAL;
        string_len = strnlen(str, len);
        if (dest && len) {
                memcpy(dest, str, string_len);
@@ -441,17 +520,27 @@ void *lib_ring_buffer_read_offset_address(struct lttng_ust_lib_ring_buffer_backe
                                          struct lttng_ust_shm_handle *handle)
 {
        struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
-       struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
-       const struct lttng_ust_lib_ring_buffer_config *config = &chanb->config;
+       struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+       struct channel_backend *chanb;
+       const struct lttng_ust_lib_ring_buffer_config *config;
        unsigned long sb_bindex, id;
 
+       chanb = &shmp(handle, bufb->chan)->backend;
+       if (!chanb)
+               return NULL;
+       config = &chanb->config;
        offset &= chanb->buf_size - 1;
        id = bufb->buf_rsb.id;
        sb_bindex = subbuffer_id_get_index(config, id);
        rpages = shmp_index(handle, bufb->array, sb_bindex);
+       if (!rpages)
+               return NULL;
        CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
                     && subbuffer_id_is_noref(config, id));
-       return shmp_index(handle, shmp(handle, rpages->shmp)->p, offset & (chanb->subbuf_size - 1));
+       backend_pages = shmp(handle, rpages->shmp);
+       if (!backend_pages)
+               return NULL;
+       return shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
 }
 
 /**
@@ -470,16 +559,30 @@ void *lib_ring_buffer_offset_address(struct lttng_ust_lib_ring_buffer_backend *b
 {
        size_t sbidx;
        struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
-       struct channel_backend *chanb = &shmp(handle, bufb->chan)->backend;
-       const struct lttng_ust_lib_ring_buffer_config *config = &chanb->config;
+       struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+       struct channel_backend *chanb;
+       const struct lttng_ust_lib_ring_buffer_config *config;
        unsigned long sb_bindex, id;
+       struct lttng_ust_lib_ring_buffer_backend_subbuffer *sb;
 
+       chanb = &shmp(handle, bufb->chan)->backend;
+       if (!chanb)
+               return NULL;
+       config = &chanb->config;
        offset &= chanb->buf_size - 1;
        sbidx = offset >> chanb->subbuf_size_order;
-       id = shmp_index(handle, bufb->buf_wsb, sbidx)->id;
+       sb = shmp_index(handle, bufb->buf_wsb, sbidx);
+       if (!sb)
+               return NULL;
+       id = sb->id;
        sb_bindex = subbuffer_id_get_index(config, id);
        rpages = shmp_index(handle, bufb->array, sb_bindex);
+       if (!rpages)
+               return NULL;
        CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
                     && subbuffer_id_is_noref(config, id));
-       return shmp_index(handle, shmp(handle, rpages->shmp)->p, offset & (chanb->subbuf_size - 1));
+       backend_pages = shmp(handle, rpages->shmp);
+       if (!backend_pages)
+               return NULL;
+       return shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
 }
This page took 0.03027 seconds and 4 git commands to generate.