#include <linux/cpu.h>
#include <linux/mm.h>
-#include "../../wrapper/symbols.h" /* for wrapper_vmalloc_sync_all() */
+#include "../../wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
#include "../../wrapper/ringbuffer/config.h"
#include "../../wrapper/ringbuffer/backend.h"
#include "../../wrapper/ringbuffer/frontend.h"
return -EPERM;
/* Check that the subbuffer size is larger than a page. */
- CHAN_WARN_ON(chanb, subbuf_size < PAGE_SIZE);
+ if (subbuf_size < PAGE_SIZE)
+ return -EINVAL;
/*
* Make sure the number of subbuffers and subbuffer size are power of 2.
}
EXPORT_SYMBOL_GPL(_lib_ring_buffer_write);
+
+/**
+ * lib_ring_buffer_memset - write len bytes of c to a ring_buffer buffer.
+ * @bufb : buffer backend
+ * @offset : offset within the buffer
+ * @c : the byte to write
+ * @len : length to write
+ * @pagecpy : page size copied so far
+ */
+void _lib_ring_buffer_memset(struct lib_ring_buffer_backend *bufb,
+ size_t offset,
+ int c, size_t len, ssize_t pagecpy)
+{
+ struct channel_backend *chanb = &bufb->chan->backend;
+ const struct lib_ring_buffer_config *config = chanb->config;
+ size_t sbidx, index;
+ struct lib_ring_buffer_backend_pages *rpages;
+ unsigned long sb_bindex, id;
+
+ do {
+ len -= pagecpy;
+ offset += pagecpy;
+ sbidx = offset >> chanb->subbuf_size_order;
+ index = (offset & (chanb->subbuf_size - 1)) >> PAGE_SHIFT;
+
+ /*
+ * Underlying layer should never ask for writes across
+ * subbuffers.
+ */
+ CHAN_WARN_ON(chanb, offset >= chanb->buf_size);
+
+ pagecpy = min_t(size_t, len, PAGE_SIZE - (offset & ~PAGE_MASK));
+ id = bufb->buf_wsb[sbidx].id;
+ sb_bindex = subbuffer_id_get_index(config, id);
+ rpages = bufb->array[sb_bindex];
+ CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
+ && subbuffer_id_is_noref(config, id));
+ lib_ring_buffer_do_memset(rpages->p[index].virt
+ + (offset & ~PAGE_MASK),
+ c, pagecpy);
+ } while (unlikely(len != pagecpy));
+}
+EXPORT_SYMBOL_GPL(_lib_ring_buffer_memset);
+
+
+/**
+ * lib_ring_buffer_copy_from_user - write user data to a ring_buffer buffer.
+ * @bufb : buffer backend
+ * @offset : offset within the buffer
+ * @src : source address
+ * @len : length to write
+ * @pagecpy : page size copied so far
+ *
+ * This function deals with userspace pointers, it should never be called
+ * directly without having the src pointer checked with access_ok()
+ * previously.
+ */
+void _lib_ring_buffer_copy_from_user(struct lib_ring_buffer_backend *bufb,
+ size_t offset,
+ const void __user *src, size_t len,
+ ssize_t pagecpy)
+{
+ struct channel_backend *chanb = &bufb->chan->backend;
+ const struct lib_ring_buffer_config *config = chanb->config;
+ size_t sbidx, index;
+ struct lib_ring_buffer_backend_pages *rpages;
+ unsigned long sb_bindex, id;
+ int ret;
+
+ do {
+ len -= pagecpy;
+ src += pagecpy;
+ offset += pagecpy;
+ sbidx = offset >> chanb->subbuf_size_order;
+ index = (offset & (chanb->subbuf_size - 1)) >> PAGE_SHIFT;
+
+ /*
+ * Underlying layer should never ask for writes across
+ * subbuffers.
+ */
+ CHAN_WARN_ON(chanb, offset >= chanb->buf_size);
+
+ pagecpy = min_t(size_t, len, PAGE_SIZE - (offset & ~PAGE_MASK));
+ id = bufb->buf_wsb[sbidx].id;
+ sb_bindex = subbuffer_id_get_index(config, id);
+ rpages = bufb->array[sb_bindex];
+ CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
+ && subbuffer_id_is_noref(config, id));
+ ret = lib_ring_buffer_do_copy_from_user(rpages->p[index].virt
+ + (offset & ~PAGE_MASK),
+ src, pagecpy) != 0;
+ if (ret > 0) {
+ offset += (pagecpy - ret);
+ len -= (pagecpy - ret);
+ _lib_ring_buffer_memset(bufb, offset, 0, len, 0);
+ break; /* stop copy */
+ }
+ } while (unlikely(len != pagecpy));
+}
+EXPORT_SYMBOL_GPL(_lib_ring_buffer_copy_from_user);
+
/**
* lib_ring_buffer_read - read data from ring_buffer_buffer.
* @bufb : buffer backend
struct channel_backend *chanb = &bufb->chan->backend;
const struct lib_ring_buffer_config *config = chanb->config;
size_t index;
- ssize_t pagecpy, orig_len;
+ ssize_t pagecpy;
struct lib_ring_buffer_backend_pages *rpages;
unsigned long sb_bindex, id;
- orig_len = len;
offset &= chanb->buf_size - 1;
index = (offset & (chanb->subbuf_size - 1)) >> PAGE_SHIFT;
if (unlikely(!len))