/*
* Public API and common code for kernel->userspace relay file support.
*
- * See Documentation/filesystems/relayfs.txt for an overview of relayfs.
+ * See Documentation/filesystems/relay.txt for an overview.
*
* Copyright (C) 2002-2005 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp
* Copyright (C) 1999-2005 - Karim Yaghmour (karim@opersys.com)
}
/*
- * nopage() vm_op implementation for relay file mapping.
+ * fault() vm_op implementation for relay file mapping.
*/
-static struct page *relay_buf_nopage(struct vm_area_struct *vma,
- unsigned long address,
- int *type)
+static int relay_buf_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct page *page;
struct rchan_buf *buf = vma->vm_private_data;
- unsigned long offset = address - vma->vm_start;
+ pgoff_t pgoff = vmf->pgoff;
- if (address > vma->vm_end)
- return NOPAGE_SIGBUS; /* Disallow mremap */
if (!buf)
- return NOPAGE_OOM;
+ return VM_FAULT_OOM;
- page = vmalloc_to_page(buf->start + offset);
+ page = vmalloc_to_page(buf->start + (pgoff << PAGE_SHIFT));
if (!page)
- return NOPAGE_OOM;
+ return VM_FAULT_SIGBUS;
get_page(page);
+ vmf->page = page;
- if (type)
- *type = VM_FAULT_MINOR;
-
- return page;
+ return 0;
}
/*
* vm_ops for relay file mappings.
*/
static struct vm_operations_struct relay_file_mmap_ops = {
- .nopage = relay_buf_nopage,
+ .fault = relay_buf_fault,
.close = relay_file_mmap_close,
};
+/*
+ * allocate an array of pointers of struct page
+ */
+static struct page **relay_alloc_page_array(unsigned int n_pages)
+{
+ struct page **array;
+ size_t pa_size = n_pages * sizeof(struct page *);
+
+ if (pa_size > PAGE_SIZE) {
+ array = vmalloc(pa_size);
+ if (array)
+ memset(array, 0, pa_size);
+ } else {
+ array = kzalloc(pa_size, GFP_KERNEL);
+ }
+ return array;
+}
+
+/*
+ * free an array of pointers of struct page
+ */
+static void relay_free_page_array(struct page **array)
+{
+ if (is_vmalloc_addr(array))
+ vfree(array);
+ else
+ kfree(array);
+}
+
/**
* relay_mmap_buf: - mmap channel buffer to process address space
* @buf: relay channel buffer
*
* Caller should already have grabbed mmap_sem.
*/
-int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma)
+static int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma)
{
unsigned long length = vma->vm_end - vma->vm_start;
struct file *filp = vma->vm_file;
return -EINVAL;
vma->vm_ops = &relay_file_mmap_ops;
+ vma->vm_flags |= VM_DONTEXPAND;
vma->vm_private_data = buf;
buf->chan->cb->buf_mapped(buf, filp);
*size = PAGE_ALIGN(*size);
n_pages = *size >> PAGE_SHIFT;
- buf->page_array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL);
+ buf->page_array = relay_alloc_page_array(n_pages);
if (!buf->page_array)
return NULL;
depopulate:
for (j = 0; j < i; j++)
__free_page(buf->page_array[j]);
- kfree(buf->page_array);
+ relay_free_page_array(buf->page_array);
return NULL;
}
*
* Returns channel buffer if successful, %NULL otherwise.
*/
-struct rchan_buf *relay_create_buf(struct rchan *chan)
+static struct rchan_buf *relay_create_buf(struct rchan *chan)
{
struct rchan_buf *buf = kzalloc(sizeof(struct rchan_buf), GFP_KERNEL);
if (!buf)
*
* Should only be called from kref_put().
*/
-void relay_destroy_channel(struct kref *kref)
+static void relay_destroy_channel(struct kref *kref)
{
struct rchan *chan = container_of(kref, struct rchan, kref);
kfree(chan);
* relay_destroy_buf - destroy an rchan_buf struct and associated buffer
* @buf: the buffer struct
*/
-void relay_destroy_buf(struct rchan_buf *buf)
+static void relay_destroy_buf(struct rchan_buf *buf)
{
struct rchan *chan = buf->chan;
unsigned int i;
vunmap(buf->start);
for (i = 0; i < buf->page_count; i++)
__free_page(buf->page_array[i]);
- kfree(buf->page_array);
+ relay_free_page_array(buf->page_array);
}
chan->buf[buf->cpu] = NULL;
kfree(buf->padding);
* rchan_buf_struct and the channel buffer. Should only be called from
* kref_put().
*/
-void relay_remove_buf(struct kref *kref)
+static void relay_remove_buf(struct kref *kref)
{
struct rchan_buf *buf = container_of(kref, struct rchan_buf, kref);
buf->chan->cb->remove_buf_file(buf->dentry);
*
* Returns 1 if the buffer is empty, 0 otherwise.
*/
-int relay_buf_empty(struct rchan_buf *buf)
+static int relay_buf_empty(struct rchan_buf *buf)
{
return (buf->subbufs_produced - buf->subbufs_consumed) ? 0 : 1;
}
-EXPORT_SYMBOL_GPL(relay_buf_empty);
/**
* relay_buf_full - boolean, is the channel buffer full?
if (!chan)
return;
- if (chan->is_global && chan->buf[0]) {
+ if (chan->is_global && chan->buf[0]) {
__relay_reset(chan->buf[0], 0);
return;
}
free_buf:
relay_destroy_buf(buf);
+ buf = NULL;
free_name:
kfree(tmpname);
end:
kref_get(&buf->kref);
filp->private_data = buf;
- return 0;
+ return nonseekable_open(inode, filp);
}
/**
buf->subbufs_consumed = consumed;
buf->bytes_consumed = 0;
}
-
+
produced = (produced % n_subbufs) * subbuf_size + buf->offset;
consumed = (consumed % n_subbufs) * subbuf_size + buf->bytes_consumed;
if (consumed > produced)
produced += n_subbufs * subbuf_size;
-
+
if (consumed == produced)
return 0;
.get = generic_pipe_buf_get,
};
+static void relay_page_release(struct splice_pipe_desc *spd, unsigned int i)
+{
+}
+
/*
* subbuf_splice_actor - splice up to one subbuf's worth of data
*/
unsigned int flags,
int *nonpad_ret)
{
- unsigned int pidx, poff, total_len, subbuf_pages, ret;
+ unsigned int pidx, poff, total_len, subbuf_pages, nr_pages, ret;
struct rchan_buf *rbuf = in->private_data;
unsigned int subbuf_size = rbuf->chan->subbuf_size;
uint64_t pos = (uint64_t) *ppos;
.partial = partial,
.flags = flags,
.ops = &relay_pipe_buf_ops,
+ .spd_release = relay_page_release,
};
if (rbuf->subbufs_produced == rbuf->subbufs_consumed)
subbuf_pages = rbuf->chan->alloc_size >> PAGE_SHIFT;
pidx = (read_start / PAGE_SIZE) % subbuf_pages;
poff = read_start & ~PAGE_MASK;
+ nr_pages = min_t(unsigned int, subbuf_pages, PIPE_BUFFERS);
- for (total_len = 0; spd.nr_pages < subbuf_pages; spd.nr_pages++) {
+ for (total_len = 0; spd.nr_pages < nr_pages; spd.nr_pages++) {
unsigned int this_len, this_end, private;
unsigned int cur_pos = read_start + total_len;
ret = 0;
spliced = 0;
- while (len) {
+ while (len && !spliced) {
ret = subbuf_splice_actor(in, ppos, pipe, len, flags, &nonpad_ret);
if (ret < 0)
break;
projects / linux-2.6-omap-h63xx.git / blobdiff