Added missing tegra files.HEADmaster

3 files changed, 1111 insertions, 0 deletions

diff --git a/mm/ashmem.c b/mm/ashmem.c
new file mode 100644
index 00000000000..66e3f23ee33
--- /dev/null
+++ b/mm/ashmem.c
@@ -0,0 +1,748 @@
+/* mm/ashmem.c
+**
+** Anonymous Shared Memory Subsystem, ashmem
+**
+** Copyright (C) 2008 Google, Inc.
+**
+** Robert Love <rlove@google.com>
+**
+** This software is licensed under the terms of the GNU General Public
+** License version 2, as published by the Free Software Foundation, and
+** may be copied, distributed, and modified under those terms.
+**
+** This program 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 General Public License for more details.
+*/
+
+#include <linux/module.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/security.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/uaccess.h>
+#include <linux/personality.h>
+#include <linux/bitops.h>
+#include <linux/mutex.h>
+#include <linux/shmem_fs.h>
+#include <linux/ashmem.h>
+
+#define ASHMEM_NAME_PREFIX "dev/ashmem/"
+#define ASHMEM_NAME_PREFIX_LEN (sizeof(ASHMEM_NAME_PREFIX) - 1)
+#define ASHMEM_FULL_NAME_LEN (ASHMEM_NAME_LEN + ASHMEM_NAME_PREFIX_LEN)
+
+/*
+ * ashmem_area - anonymous shared memory area
+ * Lifecycle: From our parent file's open() until its release()
+ * Locking: Protected by `ashmem_mutex'
+ * Big Note: Mappings do NOT pin this structure; it dies on close()
+ */
+struct ashmem_area {
+        char name[ASHMEM_FULL_NAME_LEN];/* optional name for /proc/pid/maps */
+        struct list_head unpinned_list; /* list of all ashmem areas */
+        struct file *file;              /* the shmem-based backing file */
+        size_t size;                    /* size of the mapping, in bytes */
+        unsigned long prot_mask;        /* allowed prot bits, as vm_flags */
+};
+
+/*
+ * ashmem_range - represents an interval of unpinned (evictable) pages
+ * Lifecycle: From unpin to pin
+ * Locking: Protected by `ashmem_mutex'
+ */
+struct ashmem_range {
+        struct list_head lru;           /* entry in LRU list */
+        struct list_head unpinned;      /* entry in its area's unpinned list */
+        struct ashmem_area *asma;       /* associated area */
+        size_t pgstart;                 /* starting page, inclusive */
+        size_t pgend;                   /* ending page, inclusive */
+        unsigned int purged;            /* ASHMEM_NOT or ASHMEM_WAS_PURGED */
+};
+
+/* LRU list of unpinned pages, protected by ashmem_mutex */
+static LIST_HEAD(ashmem_lru_list);
+
+/* Count of pages on our LRU list, protected by ashmem_mutex */
+static unsigned long lru_count;
+
+/*
+ * ashmem_mutex - protects the list of and each individual ashmem_area
+ *
+ * Lock Ordering: ashmex_mutex -> i_mutex -> i_alloc_sem
+ */
+static DEFINE_MUTEX(ashmem_mutex);
+
+static struct kmem_cache *ashmem_area_cachep __read_mostly;
+static struct kmem_cache *ashmem_range_cachep __read_mostly;
+
+#define range_size(range) \
+  ((range)->pgend - (range)->pgstart + 1)
+
+#define range_on_lru(range) \
+  ((range)->purged == ASHMEM_NOT_PURGED)
+
+#define page_range_subsumes_range(range, start, end) \
+  (((range)->pgstart >= (start)) && ((range)->pgend <= (end)))
+
+#define page_range_subsumed_by_range(range, start, end) \
+  (((range)->pgstart <= (start)) && ((range)->pgend >= (end)))
+
+#define page_in_range(range, page) \
+ (((range)->pgstart <= (page)) && ((range)->pgend >= (page)))
+
+#define page_range_in_range(range, start, end) \
+  (page_in_range(range, start) || page_in_range(range, end) || \
+   page_range_subsumes_range(range, start, end))
+
+#define range_before_page(range, page) \
+  ((range)->pgend < (page))
+
+#define PROT_MASK               (PROT_EXEC | PROT_READ | PROT_WRITE)
+
+static inline void lru_add(struct ashmem_range *range)
+{
+        list_add_tail(&range->lru, &ashmem_lru_list);
+        lru_count += range_size(range);
+}
+
+static inline void lru_del(struct ashmem_range *range)
+{
+        list_del(&range->lru);
+        lru_count -= range_size(range);
+}
+
+/*
+ * range_alloc - allocate and initialize a new ashmem_range structure
+ *
+ * 'asma' - associated ashmem_area
+ * 'prev_range' - the previous ashmem_range in the sorted asma->unpinned list
+ * 'purged' - initial purge value (ASMEM_NOT_PURGED or ASHMEM_WAS_PURGED)
+ * 'start' - starting page, inclusive
+ * 'end' - ending page, inclusive
+ *
+ * Caller must hold ashmem_mutex.
+ */
+static int range_alloc(struct ashmem_area *asma,
+                       struct ashmem_range *prev_range, unsigned int purged,
+                       size_t start, size_t end)
+{
+        struct ashmem_range *range;
+
+        range = kmem_cache_zalloc(ashmem_range_cachep, GFP_KERNEL);
+        if (unlikely(!range))
+                return -ENOMEM;
+
+        range->asma = asma;
+        range->pgstart = start;
+        range->pgend = end;
+        range->purged = purged;
+
+        list_add_tail(&range->unpinned, &prev_range->unpinned);
+
+        if (range_on_lru(range))
+                lru_add(range);
+
+        return 0;
+}
+
+static void range_del(struct ashmem_range *range)
+{
+        list_del(&range->unpinned);
+        if (range_on_lru(range))
+                lru_del(range);
+        kmem_cache_free(ashmem_range_cachep, range);
+}
+
+/*
+ * range_shrink - shrinks a range
+ *
+ * Caller must hold ashmem_mutex.
+ */
+static inline void range_shrink(struct ashmem_range *range,
+                                size_t start, size_t end)
+{
+        size_t pre = range_size(range);
+
+        range->pgstart = start;
+        range->pgend = end;
+
+        if (range_on_lru(range))
+                lru_count -= pre - range_size(range);
+}
+
+static int ashmem_open(struct inode *inode, struct file *file)
+{
+        struct ashmem_area *asma;
+        int ret;
+
+        ret = generic_file_open(inode, file);
+        if (unlikely(ret))
+                return ret;
+
+        asma = kmem_cache_zalloc(ashmem_area_cachep, GFP_KERNEL);
+        if (unlikely(!asma))
+                return -ENOMEM;
+
+        INIT_LIST_HEAD(&asma->unpinned_list);
+        memcpy(asma->name, ASHMEM_NAME_PREFIX, ASHMEM_NAME_PREFIX_LEN);
+        asma->prot_mask = PROT_MASK;
+        file->private_data = asma;
+
+        return 0;
+}
+
+static int ashmem_release(struct inode *ignored, struct file *file)
+{
+        struct ashmem_area *asma = file->private_data;
+        struct ashmem_range *range, *next;
+
+        mutex_lock(&ashmem_mutex);
+        list_for_each_entry_safe(range, next, &asma->unpinned_list, unpinned)
+                range_del(range);
+        mutex_unlock(&ashmem_mutex);
+
+        if (asma->file)
+                fput(asma->file);
+        kmem_cache_free(ashmem_area_cachep, asma);
+
+        return 0;
+}
+
+static ssize_t ashmem_read(struct file *file, char __user *buf,
+                           size_t len, loff_t *pos)
+{
+        struct ashmem_area *asma = file->private_data;
+        int ret = 0;
+
+        mutex_lock(&ashmem_mutex);
+
+        /* If size is not set, or set to 0, always return EOF. */
+        if (asma->size == 0) {
+                goto out;
+        }
+
+        if (!asma->file) {
+                ret = -EBADF;
+