fs.c

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#include "local.h"

#include <linux/fs.h>
#include <linux/backing-dev.h>
#include <linux/mount.h>

/*
 * Some subsystems, such as the blockdev layer, implement their data
 * hierarchy as a pseudo file system. To not incorporate the complete
 * Linux VFS implementation, we cut this down to an own one only for
 * pseudo file systems.
 */
static LIST_HEAD(dde_vfs_mounts);

#define MAX_RA_PAGES 1

void default_unplug_io_fn(struct backing_dev_info *bdi, struct page* p)
{
}

struct backing_dev_info default_backing_dev_info = {
        .ra_pages     = MAX_RA_PAGES,
        .state        = 0,
        .capabilities = BDI_CAP_MAP_COPY,
        .unplug_io_fn = default_unplug_io_fn,
};

int seq_printf(struct seq_file *m, const char *f, ...)
{
        WARN_UNIMPL;
        return 0;
}

int generic_writepages(struct address_space *mapping,
                       struct writeback_control *wbc)
{
        WARN_UNIMPL;
        return 0;
}


/**************************************
 * Filemap stuff                      *
 **************************************/
struct page * find_get_page(struct address_space *mapping, unsigned long offset)
{
        WARN_UNIMPL;
        return NULL;
}

void unlock_page(struct page *page)
{
        WARN_UNIMPL;
}

int test_set_page_writeback(struct page *page)
{
        WARN_UNIMPL;
        return 0;
}

void end_page_writeback(struct page *page)
{
        WARN_UNIMPL;
}

void do_invalidatepage(struct page *page, unsigned long offset)
{
        WARN_UNIMPL;
}

int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page)
{
        WARN_UNIMPL;
        return 0;
}

static struct vfsmount *dde_kern_mount(struct file_system_type *type,
                                                                           int flags, const char *name,
                                                                           void *data)
{
        struct list_head *pos, *head;
        int error;

        head = &dde_vfs_mounts;
        __list_for_each(pos, head) {
                struct vfsmount *mnt = list_entry(pos, struct vfsmount, next);
                if (strcmp(name, mnt->name) == 0) {
                        printk("FS type %s already mounted!?\n", name);
                        BUG();
                        return NULL;
                }
        }

        struct vfsmount *m = kzalloc(sizeof(*m), GFP_KERNEL);
        m->fs_type = type;
        m->name = kmalloc(strlen(name) + 1, GFP_KERNEL);
        memcpy(m->name, name, strlen(name) + 1);

        error = type->get_sb(type, flags, name, data, m);
        BUG_ON(error);

        list_add_tail(&m->next, &dde_vfs_mounts);

        return m;
}

struct vfsmount *kern_mount_data(struct file_system_type *type, void *data)
{
        return dde_kern_mount(type, 0, type->name, NULL);
}

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