[PATCH v10] fs: imgdafs: Add IMG DAFS filesystem for metag
From: James Hogan
Date: Fri Dec 13 2013 - 08:16:49 EST
Add the IMG Debug Adapter File System (DAFS) for metag, which uses
SWITCH operations to communicate with a file server on a host computer
via a JTAG debug adapter.
Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Cc: linux-metag@xxxxxxxxxxxxxxx
---
I haven't received any feedback on this patch since v6 in March. If it's
acceptable, how should it find its way into mainline? I'm happy to take
it in the arch/metag tree if somebody on the fs side would be willing to
ACK it.
v10 (Dec 2013):
* add release() callback to write back file mappings (same problem as
fixed in hostfs by commit 65984ff9d217 um: hostfs: Fix writeback)
* implement basic fsync() to write back file mappings
* use simple_dentry_operations, like hostfs change in commit
b26d4cd385fc (consolidate simple ->d_delete() instances)
v9 (Jul 2013):
* updated dafs_readdir to use iterate() file operation and dir_emit()
to match changes in v3.11-rc1.
v8 (May 2013):
* enabled building as a module (commit e605ff8 merged during v3.10
merge window exports the necessary symbols)
v7 (Mar 2013):
* use explicit sized types in da_stat and da_finddata (Al Viro)
* move IMGDAFS_SUPER_MAGIC to <linux/magic.h> (Al Viro)
* use fmode_t instead of int in a couple of places (Al Viro)
* removed "will unlock" comment (Al Viro)
* use kmalloc and init hi->mode explicitly (Al Viro)
* kmalloc instead of using dynamic array for path (Al Viro)
* use file_inode() helper in dafs_readdir (Al Viro)
v6 (Mar 2013):
* use file_inode() helper introduced in v3.9-rc1
* remove dafs_iops as it only contained directory methods
* add MODULE_ALIAS_FS()
v5 (Mar 2013):
* removed arch/metag changes (the arch/metag patchset it was
previously part of is now mainline with those changes)
v4 (Jan 2013):
* clean up fscall similarly to chancall in tty/metag_da
v2 (Dec 2012):
* fixed fserrno problem (Al Viro)
* renamed to imgdafs
---
fs/Kconfig | 1 +
fs/Makefile | 1 +
fs/imgdafs/Kconfig | 6 +
fs/imgdafs/Makefile | 7 +
fs/imgdafs/imgdafs.h | 82 +++++
fs/imgdafs/inode.c | 843 +++++++++++++++++++++++++++++++++++++++++++++
include/uapi/linux/magic.h | 1 +
7 files changed, 941 insertions(+)
create mode 100644 fs/imgdafs/Kconfig
create mode 100644 fs/imgdafs/Makefile
create mode 100644 fs/imgdafs/imgdafs.h
create mode 100644 fs/imgdafs/inode.c
diff --git a/fs/Kconfig b/fs/Kconfig
index c229f828eb01..839ef10842eb 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -212,6 +212,7 @@ source "fs/ufs/Kconfig"
source "fs/exofs/Kconfig"
source "fs/f2fs/Kconfig"
source "fs/efivarfs/Kconfig"
+source "fs/imgdafs/Kconfig"
endif # MISC_FILESYSTEMS
diff --git a/fs/Makefile b/fs/Makefile
index 4fe6df3ec28f..25a93c793b74 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -126,3 +126,4 @@ obj-y += exofs/ # Multiple modules
obj-$(CONFIG_CEPH_FS) += ceph/
obj-$(CONFIG_PSTORE) += pstore/
obj-$(CONFIG_EFIVAR_FS) += efivarfs/
+obj-$(CONFIG_IMGDAFS_FS) += imgdafs/
diff --git a/fs/imgdafs/Kconfig b/fs/imgdafs/Kconfig
new file mode 100644
index 000000000000..844e6cf0e9ed
--- /dev/null
+++ b/fs/imgdafs/Kconfig
@@ -0,0 +1,6 @@
+config IMGDAFS_FS
+ tristate "Meta DA filesystem support"
+ depends on METAG_DA
+ help
+ This enables the DA filesystem, which allows Linux to
+ to access files on a system attached via a debug adapter.
diff --git a/fs/imgdafs/Makefile b/fs/imgdafs/Makefile
new file mode 100644
index 000000000000..169a3c6b5fa4
--- /dev/null
+++ b/fs/imgdafs/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for DAfs the Debug Adapter filesystem.
+#
+
+obj-$(CONFIG_IMGDAFS_FS) += imgdafs.o
+
+imgdafs-objs := inode.o
diff --git a/fs/imgdafs/imgdafs.h b/fs/imgdafs/imgdafs.h
new file mode 100644
index 000000000000..0350220eb321
--- /dev/null
+++ b/fs/imgdafs/imgdafs.h
@@ -0,0 +1,82 @@
+#ifndef _IMGDAFS_H_
+#define _IMGDAFS_H_
+
+#include <linux/types.h>
+
+#define DA_OP_OPEN 0
+#define DA_OP_CREAT 1
+#define DA_OP_READ 2
+#define DA_OP_WRITE 3
+#define DA_OP_CLOSE 4
+#define DA_OP_LINK 5
+#define DA_OP_LSEEK 6
+#define DA_OP_UNLINK 7
+#define DA_OP_ISATTY 8
+#define DA_OP_FCNTL 9
+#define DA_OP_STAT 10
+#define DA_OP_FSTAT 11
+#define DA_OP_GETCWD 12
+#define DA_OP_CHDIR 13
+#define DA_OP_MKDIR 14
+#define DA_OP_RMDIR 15
+#define DA_OP_FINDFIRST 16
+#define DA_OP_FINDNEXT 17
+#define DA_OP_FINDCLOSE 18
+#define DA_OP_CHMOD 19
+#define DA_OP_PREAD 20
+#define DA_OP_PWRITE 21
+
+#define OS_TYPE_FILE 1
+#define OS_TYPE_DIR 2
+#define OS_TYPE_SYMLINK 3
+#define OS_TYPE_CHARDEV 4
+#define OS_TYPE_BLOCKDEV 5
+#define OS_TYPE_FIFO 6
+#define OS_TYPE_SOCK 7
+
+#define DA_O_RDONLY 0
+#define DA_O_WRONLY 1
+#define DA_O_RDWR 2
+#define DA_O_APPEND 8
+#define DA_O_CREAT 0x0200
+#define DA_O_TRUNC 0x0400
+#define DA_O_EXCL 0x0800
+
+#define DA_O_AFFINITY_THREAD_0 0x10000
+#define DA_O_AFFINITY_THREAD_1 0x20000
+#define DA_O_AFFINITY_THREAD_2 0x40000
+#define DA_O_AFFINITY_THREAD_3 0x80000
+#define DA_O_AFFINITY_SHIFT 16
+
+#define DA_S_IWUSR 0200 /* 0x80 */
+#define DA_S_IRUSR 0400 /* 0x100 */
+
+struct da_stat {
+ s16 st_dev;
+ u16 st_ino;
+ u32 st_mode;
+ u16 st_nlink;
+ u16 st_uid;
+ u16 st_gid;
+ s16 st_rdev;
+ s32 st_size;
+ s32 st_atime;
+ s32 st_spare1;
+ s32 st_mtime;
+ s32 st_spare2;
+ s32 st_ctime;
+ s32 st_spare3;
+ s32 st_blksize;
+ s32 st_blocks;
+ s32 st_spare4[2];
+};
+
+#define _A_SUBDIR 0x10
+
+struct da_finddata {
+ u32 size;
+ u32 attrib;
+ u8 name[260];
+};
+
+#endif
diff --git a/fs/imgdafs/inode.c b/fs/imgdafs/inode.c
new file mode 100644
index 000000000000..f444f67af0d8
--- /dev/null
+++ b/fs/imgdafs/inode.c
@@ -0,0 +1,843 @@
+/*
+ * Copyright (C) 2008-2013 Imagination Technologies Ltd.
+ * Licensed under the GPL
+ *
+ * Based on hostfs for UML.
+ *
+ */
+
+#include <linux/fs.h>
+#include <linux/magic.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/slab.h>
+
+#include <asm/da.h>
+#include <asm/hwthread.h>
+
+#include "imgdafs.h"
+
+static int fscall(int in_system_call, int in_arg1, int in_arg2, int in_arg3,
+ int in_arg4, int in_arg5, int *fserrno)
+{
+ register int arg1 asm("D1Ar1") = in_arg1;
+ register int arg2 asm("D0Ar2") = in_arg2;
+ register int arg3 asm("D1Ar3") = in_arg3;
+ register int arg4 asm("D0Ar4") = in_arg4;
+ register int arg5 asm("D1Ar5") = in_arg5;
+ register int system_call asm("D0Ar6") = in_system_call;
+ register int result asm("D0Re0");
+ register int errno asm("D1Re0");
+
+ asm volatile (
+ "MSETL [A0StP++], %7,%5,%3\n\t"
+ "ADD A0StP, A0StP, #8\n\t"
+ "SWITCH #0x0C00208\n\t"
+ "GETL %0, %1, [A0StP+#-8]\n\t"
+ "SUB A0StP, A0StP, #(4*6)+8\n\t"
+ : "=r" (result),
+ "=r" (errno)
+ : "r" (arg1),
+ "r" (arg2),
+ "r" (arg3),
+ "r" (arg4),
+ "r" (arg5),
+ "r" (system_call)
+ : "memory");
+
+ if (fserrno)
+ *fserrno = errno;
+
+ return result;
+}
+
+struct dafs_inode_info {
+ int fd;
+ fmode_t mode;
+ struct inode vfs_inode;
+};
+
+static inline struct dafs_inode_info *DAFS_I(struct inode *inode)
+{
+ return container_of(inode, struct dafs_inode_info, vfs_inode);
+}
+
+#define FILE_DAFS_I(file) DAFS_I(file_inode(file))
+
+static const struct inode_operations dafs_dir_iops;
+
+static char *__dentry_name(struct dentry *dentry, char *name)
+{
+ char *p = dentry_path_raw(dentry, name, PATH_MAX);
+ char *root;
+ size_t len;
+
+ root = dentry->d_sb->s_fs_info;
+ len = strlen(root);
+ if (IS_ERR(p)) {
+ __putname(name);
+ return NULL;
+ }
+
+ strlcpy(name, root, PATH_MAX);
+ if (len > p - name) {
+ __putname(name);
+ return NULL;
+ }
+ if (p > name + len) {
+ char *s = name + len;
+ while ((*s++ = *p++) != '\0')
+ ;
+ }
+ return name;
+}
+
+static char *dentry_name(struct dentry *dentry)
+{
+ char *name = __getname();
+ if (!name)
+ return NULL;
+
+ return __dentry_name(dentry, name);
+}
+
+static int stat_file(const char *path, struct da_stat *p, int fd)
+{
+ int ret;
+ int fserrno;
+ memset(p, 0, sizeof(*p));
+
+ if (fd >= 0) {
+ ret = fscall(DA_OP_FSTAT, fd, (int)p, 0, 0, 0, &fserrno);
+ if (ret < 0) {
+ /* Some versions of Codescape do not fill out errno. */
+ if (ret < 0 && fserrno == 0)
+ fserrno = ENOENT;
+ return -fserrno;
+ }
+ } else {
+ ret = fscall(DA_OP_STAT, (int)path, (int)p, strlen(path), 0, 0,
+ &fserrno);
+ if (ret < 0) {
+ /* Some versions of Codescape do not fill out errno. */
+ if (ret < 0 && fserrno == 0)
+ fserrno = ENOENT;
+ return -fserrno;
+ }
+ }
+
+ return 0;
+}
+
+static struct inode *dafs_iget(struct super_block *sb)
+{
+ struct inode *inode = new_inode(sb);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ return inode;
+}
+
+static struct inode *dafs_alloc_inode(struct super_block *sb)
+{
+ struct dafs_inode_info *hi;
+
+ hi = kmalloc(sizeof(*hi), GFP_KERNEL);
+ if (hi == NULL)
+ return NULL;
+
+ hi->fd = -1;
+ hi->mode = 0;
+ inode_init_once(&hi->vfs_inode);
+ return &hi->vfs_inode;
+}
+
+static void close_file(void *stream)
+{
+ int fd = *((int *) stream);
+
+ fscall(DA_OP_CLOSE, fd, 0, 0, 0, 0, NULL);
+}
+
+static void dafs_evict_inode(struct inode *inode)
+{
+ truncate_inode_pages(&inode->i_data, 0);
+ clear_inode(inode);
+ if (DAFS_I(inode)->fd != -1) {
+ close_file(&DAFS_I(inode)->fd);
+ DAFS_I(inode)->fd = -1;
+ }
+}
+
+static void dafs_i_callback(struct rcu_head *head)
+{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+ kfree(DAFS_I(inode));
+}
+
+static void dafs_destroy_inode(struct inode *inode)
+{
+ call_rcu(&inode->i_rcu, dafs_i_callback);
+}
+
+static const struct super_operations dafs_sbops = {
+ .alloc_inode = dafs_alloc_inode,
+ .drop_inode = generic_delete_inode,
+ .evict_inode = dafs_evict_inode,
+ .destroy_inode = dafs_destroy_inode,
+};
+
+static int open_dir(char *path, struct da_finddata *finddata, int *fserrno)
+{
+ int len = strlen(path);
+ char *buf;
+ int ret;
+
+ buf = kmalloc(len + 3, GFP_KERNEL);
+ if (!buf) {
+ *fserrno = ENOMEM;
+ return -1;
+ }
+
+ strcpy(buf, path);
+ if (buf[len - 1] != '/')
+ strcat(buf, "/*");
+ else
+ strcat(buf, "*");
+
+ ret = fscall(DA_OP_FINDFIRST, (int)buf, (int)finddata, 0, 0, 0,
+ fserrno);
+ kfree(buf);
+ return ret;
+}
+
+static void close_dir(int handle)
+{
+ fscall(DA_OP_FINDCLOSE, handle, 0, 0, 0, 0, NULL);
+}
+
+static int read_dir(int handle, struct da_finddata *finddata)
+{
+ return fscall(DA_OP_FINDNEXT, handle, (int)finddata, 0, 0, 0, NULL);
+}
+
+static int dafs_readdir(struct file *file, struct dir_context *ctx)
+{
+ struct inode *inode = file_inode(file);
+ struct super_block *sb = inode->i_sb;
+ char *name;
+ int handle;
+ int fserrno;
+ unsigned long long next, ino;
+ int error = 0;
+ struct da_finddata finddata;
+
+ name = dentry_name(file->f_path.dentry);
+ if (name == NULL)
+ return -ENOMEM;
+ handle = open_dir(name, &finddata, &fserrno);
+ __putname(name);
+ if (handle == -1)
+ return -fserrno;
+
+ next = 1;
+
+ if (ctx->pos == 0) {
+ if (!dir_emit(ctx, ".", ctx->pos + 1, inode->i_ino, DT_DIR))
+ goto out;
+ ctx->pos++;
+ }
+
+ while (1) {
+ error = read_dir(handle, &finddata);
+ if (error)
+ break;
+
+ if (next >= ctx->pos) {
+ size_t len = strlen(finddata.name);
+ ino = iunique(sb, 100);
+ if (!dir_emit(ctx, finddata.name, len, ino,
+ (finddata.attrib & _A_SUBDIR) ?
+ DT_DIR : DT_REG))
+ break;
+ ctx->pos++;
+ }
+ next++;
+ }
+out:
+ close_dir(handle);
+ return 0;
+}
+
+static int dafs_file_open(struct inode *ino, struct file *file)
+{
+ static DEFINE_MUTEX(open_mutex);
+ char *name;
+ fmode_t mode, fmode;
+ int flags = 0, r = 0, w = 0, fd;
+ int cpu;
+
+ fmode = file->f_mode & (FMODE_READ | FMODE_WRITE);
+ if ((fmode & DAFS_I(ino)->mode) == fmode)
+ return 0;
+
+ mode = ino->i_mode & (DA_S_IWUSR | DA_S_IRUSR);
+
+ mode |= DAFS_I(ino)->mode;
+
+ DAFS_I(ino)->mode |= fmode;
+ if (DAFS_I(ino)->mode & FMODE_READ)
+ r = 1;
+ if (DAFS_I(ino)->mode & FMODE_WRITE) {
+ w = 1;
+ r = 1;
+ }
+
+retry:
+ if (r && !w)
+ flags |= DA_O_RDONLY;
+ else if (!r && w)
+ flags |= DA_O_WRONLY;
+ else if (r && w)
+ flags |= DA_O_RDWR;
+
+ if (file->f_flags & O_CREAT)
+ flags |= DA_O_CREAT;
+
+ if (file->f_flags & O_TRUNC)
+ flags |= DA_O_TRUNC;
+
+ /*
+ * Set the affinity for this file handle to all CPUs. If we
+ * don't do this then, if the process that opened the file
+ * migrates to a different cpu, the FileServer will not accept
+ * the file handle.
+ */
+ for_each_possible_cpu(cpu) {
+ u8 hwthread = cpu_2_hwthread_id[cpu];
+ flags |= (1 << (DA_O_AFFINITY_SHIFT + hwthread));
+ }
+
+ name = dentry_name(file->f_path.dentry);
+ if (name == NULL)
+ return -ENOMEM;
+
+ fd = fscall(DA_OP_OPEN, (int)name, flags, mode, strlen(name), 0, NULL);
+ __putname(name);
+ if (fd < 0)
+ return fd;
+
+ mutex_lock(&open_mutex);
+ /* somebody else had handled it first? */
+ if ((mode & DAFS_I(ino)->mode) == mode) {
+ mutex_unlock(&open_mutex);
+ return 0;
+ }
+ if ((mode | DAFS_I(ino)->mode) != mode) {
+ mode |= DAFS_I(ino)->mode;
+ mutex_unlock(&open_mutex);
+ close_file(&fd);
+ goto retry;
+ }
+ DAFS_I(ino)->fd = fd;
+ DAFS_I(ino)->mode = mode;
+ mutex_unlock(&open_mutex);
+
+ return 0;
+}
+
+static int dafs_file_release(struct inode *inode, struct file *file)
+{
+ filemap_write_and_wait(inode->i_mapping);
+
+ return 0;
+}
+
+static int dafs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+ struct inode *inode = file->f_mapping->host;
+
+ return filemap_write_and_wait_range(inode->i_mapping, start, end);
+}
+
+static const struct file_operations dafs_file_fops = {
+ .llseek = generic_file_llseek,
+ .read = do_sync_read,
+ .splice_read = generic_file_splice_read,
+ .aio_read = generic_file_aio_read,
+ .aio_write = generic_file_aio_write,
+ .write = do_sync_write,
+ .mmap = generic_file_mmap,
+ .open = dafs_file_open,
+ .release = dafs_file_release,
+ .fsync = dafs_fsync,
+};
+
+static const struct file_operations dafs_dir_fops = {
+ .llseek = generic_file_llseek,
+ .iterate = dafs_readdir,
+ .read = generic_read_dir,
+};
+
+static int read_file(int fd, unsigned long long *offset, const char *buf,
+ int len)
+{
+ int n;
+ int fserrno;
+
+ n = fscall(DA_OP_PREAD, fd, (int)buf, len, (int)*offset, 0, &fserrno);
+
+ if (n < 0)
+ return -fserrno;
+
+ return n;
+}
+
+static int write_file(int fd, unsigned long long *offset, const char *buf,
+ int len)
+{
+ int n;
+ int fserrno;
+
+ n = fscall(DA_OP_PWRITE, fd, (int)buf, len, (int)*offset, 0, &fserrno);
+
+ if (n < 0)
+ return -fserrno;
+
+ return n;
+}
+
+static int dafs_writepage(struct page *page, struct writeback_control *wbc)
+{
+ struct address_space *mapping = page->mapping;
+ struct inode *inode = mapping->host;
+ char *buffer;
+ unsigned long long base;
+ int count = PAGE_CACHE_SIZE;
+ int end_index = inode->i_size >> PAGE_CACHE_SHIFT;
+ int err;
+
+ if (page->index >= end_index)
+ count = inode->i_size & (PAGE_CACHE_SIZE-1);
+
+ buffer = kmap(page);
+ base = ((unsigned long long) page->index) << PAGE_CACHE_SHIFT;
+
+ err = write_file(DAFS_I(inode)->fd, &base, buffer, count);
+ if (err != count) {
+ ClearPageUptodate(page);
+ goto out;
+ }
+
+ if (base > inode->i_size)
+ inode->i_size = base;
+
+ if (PageError(page))
+ ClearPageError(page);
+ err = 0;
+
+ out:
+ kunmap(page);
+
+ unlock_page(page);
+ return err;
+}
+
+static int dafs_readpage(struct file *file, struct page *page)
+{
+ char *buffer;
+ long long start;
+ int err = 0;
+
+ start = (long long) page->index << PAGE_CACHE_SHIFT;
+ buffer = kmap(page);
+ err = read_file(FILE_DAFS_I(file)->fd, &start, buffer,
+ PAGE_CACHE_SIZE);
+ if (err < 0)
+ goto out;
+
+ memset(&buffer[err], 0, PAGE_CACHE_SIZE - err);
+
+ flush_dcache_page(page);
+ SetPageUptodate(page);
+ if (PageError(page))
+ ClearPageError(page);
+ err = 0;
+ out:
+ kunmap(page);
+ unlock_page(page);
+ return err;
+}
+
+static int dafs_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
+{
+ pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+
+ *pagep = grab_cache_page_write_begin(mapping, index, flags);
+ if (!*pagep)
+ return -ENOMEM;
+ return 0;
+}
+
+static int dafs_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
+{
+ struct inode *inode = mapping->host;
+ void *buffer;
+ unsigned from = pos & (PAGE_CACHE_SIZE - 1);
+ int err;
+
+ buffer = kmap(page);
+ err = write_file(FILE_DAFS_I(file)->fd, &pos, buffer + from, copied);
+ kunmap(page);
+
+ if (!PageUptodate(page) && err == PAGE_CACHE_SIZE)
+ SetPageUptodate(page);
+
+ /*
+ * If err > 0, write_file has added err to pos, so we are comparing
+ * i_size against the last byte written.
+ */
+ if (err > 0 && (pos > inode->i_size))
+ inode->i_size = pos;
+ unlock_page(page);
+ page_cache_release(page);
+
+ return err;
+}
+
+static const struct address_space_operations dafs_aops = {
+ .writepage = dafs_writepage,
+ .readpage = dafs_readpage,
+ .set_page_dirty = __set_page_dirty_nobuffers,
+ .write_begin = dafs_write_begin,
+ .write_end = dafs_write_end,
+};
+
+static int read_name(struct inode *ino, char *name)
+{
+ dev_t rdev;
+ struct da_stat st;
+ int err = stat_file(name, &st, -1);
+ if (err)
+ return err;
+
+ /* No valid maj and min from DA.*/
+ rdev = MKDEV(0, 0);
+
+ switch (st.st_mode & S_IFMT) {
+ case S_IFDIR:
+ ino->i_op = &dafs_dir_iops;
+ ino->i_fop = &dafs_dir_fops;
+ break;
+ case S_IFCHR:
+ case S_IFBLK:
+ case S_IFIFO:
+ case S_IFSOCK:
+ init_special_inode(ino, st.st_mode & S_IFMT, rdev);
+ break;
+
+ case S_IFLNK:
+ default:
+ ino->i_fop = &dafs_file_fops;
+ ino->i_mapping->a_ops = &dafs_aops;
+ }
+
+ ino->i_ino = st.st_ino;
+ ino->i_mode = st.st_mode;
+ set_nlink(ino, st.st_nlink);
+
+ i_uid_write(ino, st.st_uid);
+ i_gid_write(ino, st.st_gid);
+ ino->i_atime.tv_sec = st.st_atime;
+ ino->i_atime.tv_nsec = 0;
+ ino->i_mtime.tv_sec = st.st_mtime;
+ ino->i_mtime.tv_nsec = 0;
+ ino->i_ctime.tv_sec = st.st_ctime;
+ ino->i_ctime.tv_nsec = 0;
+ ino->i_size = st.st_size;
+ ino->i_blocks = st.st_blocks;
+ return 0;
+}
+
+static int dafs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
+ bool excl)
+{
+ struct inode *inode;
+ char *name;
+ int error, fd;
+ int damode;
+ int creat_flags = DA_O_TRUNC | DA_O_CREAT | DA_O_WRONLY;
+ int cpu;
+
+ inode = dafs_iget(dir->i_sb);
+ if (IS_ERR(inode)) {
+ error = PTR_ERR(inode);
+ goto out;
+ }
+
+ damode = mode & (DA_S_IWUSR | DA_S_IRUSR);
+
+ error = -ENOMEM;
+ name = dentry_name(dentry);
+ if (name == NULL)
+ goto out_put;
+
+ /*
+ * creat() will only create text mode files on a Windows host
+ * at present. Replicate the creat() functionality with an
+ * open() call, which always creates binary files. Set the
+ * affinity to all hardware threads.
+ */
+ for_each_possible_cpu(cpu) {
+ u8 hwthread = cpu_2_hwthread_id[cpu];
+ creat_flags |= (1 << (DA_O_AFFINITY_SHIFT + hwthread));
+ }
+
+ fd = fscall(DA_OP_OPEN, (int)name, creat_flags, damode, strlen(name),
+ 0, NULL);
+ if (fd < 0)
+ error = fd;
+ else
+ error = read_name(inode, name);
+
+ kfree(name);
+ if (error)
+ goto out_put;
+
+ DAFS_I(inode)->fd = fd;
+ DAFS_I(inode)->mode = FMODE_READ | FMODE_WRITE;
+ d_instantiate(dentry, inode);
+ return 0;
+
+ out_put:
+ iput(inode);
+ out:
+ return error;
+}
+
+static struct dentry *dafs_lookup(struct inode *ino, struct dentry *dentry,
+ unsigned int flags)
+{
+ struct inode *inode;
+ char *name;
+ int err;
+
+ inode = dafs_iget(ino->i_sb);
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ goto out;
+ }
+
+ err = -ENOMEM;
+ name = dentry_name(dentry);
+ if (name == NULL)
+ goto out_put;
+
+ err = read_name(inode, name);
+
+ __putname(name);
+ if (err == -ENOENT) {
+ iput(inode);
+ inode = NULL;
+ } else if (err)
+ goto out_put;
+
+ d_add(dentry, inode);
+ return NULL;
+
+ out_put:
+ iput(inode);
+ out:
+ return ERR_PTR(err);
+}
+
+static int dafs_link(struct dentry *to, struct inode *ino, struct dentry *from)
+{
+ char *from_name, *to_name;
+ int err;
+
+ from_name = dentry_name(from);
+ if (from_name == NULL)
+ return -ENOMEM;
+ to_name = dentry_name(to);
+ if (to_name == NULL) {
+ __putname(from_name);
+ return -ENOMEM;
+ }
+ err = -EINVAL;
+ __putname(from_name);
+ __putname(to_name);
+ return err;
+}
+
+static int dafs_unlink(struct inode *ino, struct dentry *dentry)
+{
+ char *file;
+ int err;
+ int fserrno;
+
+ file = dentry_name(dentry);
+ if (file == NULL)
+ return -ENOMEM;
+
+ err = fscall(DA_OP_UNLINK, (int)file, 0, 0, 0, 0, &fserrno);
+ __putname(file);
+ if (err)
+ return -fserrno;
+ return 0;
+}
+
+static int do_mkdir(const char *file, int mode)
+{
+ int err;
+ int fserrno;
+
+ err = fscall(DA_OP_MKDIR, (int)file, mode, strlen(file), 0, 0,
+ &fserrno);
+ if (err)
+ return -fserrno;
+ return 0;
+}
+
+static int dafs_mkdir(struct inode *ino, struct dentry *dentry, umode_t mode)
+{
+ char *file;
+ int err;
+
+ file = dentry_name(dentry);
+ if (file == NULL)
+ return -ENOMEM;
+ err = do_mkdir(file, mode);
+ __putname(file);
+ return err;
+}
+
+static int do_rmdir(const char *file)
+{
+ int err;
+ int fserrno;
+
+ err = fscall(DA_OP_RMDIR, (int)file, strlen(file), 0, 0, 0, &fserrno);
+ if (err)
+ return -fserrno;
+ return 0;
+}
+
+static int dafs_rmdir(struct inode *ino, struct dentry *dentry)
+{
+ char *file;
+ int err;
+
+ file = dentry_name(dentry);
+ if (file == NULL)
+ return -ENOMEM;
+ err = do_rmdir(file);
+ __putname(file);
+ return err;
+}
+
+static int dafs_rename(struct inode *from_ino, struct dentry *from,
+ struct inode *to_ino, struct dentry *to)
+{
+ char *from_name, *to_name;
+ int err;
+
+ from_name = dentry_name(from);
+ if (from_name == NULL)
+ return -ENOMEM;
+ to_name = dentry_name(to);
+ if (to_name == NULL) {
+ __putname(from_name);
+ return -ENOMEM;
+ }
+ err = -EINVAL;
+ __putname(from_name);
+ __putname(to_name);
+ return err;
+}
+
+static const struct inode_operations dafs_dir_iops = {
+ .create = dafs_create,
+ .lookup = dafs_lookup,
+ .link = dafs_link,
+ .unlink = dafs_unlink,
+ .mkdir = dafs_mkdir,
+ .rmdir = dafs_rmdir,
+ .rename = dafs_rename,
+};
+
+static char *host_root_path = ".";
+
+static int dafs_fill_sb_common(struct super_block *sb, void *d, int silent)
+{
+ struct inode *root_inode;
+ int err;
+
+ sb->s_blocksize = 1024;
+ sb->s_blocksize_bits = 10;
+ sb->s_magic = IMGDAFS_SUPER_MAGIC;
+ sb->s_op = &dafs_sbops;
+ sb->s_d_op = &simple_dentry_operations;
+ sb->s_maxbytes = MAX_LFS_FILESIZE;
+
+ err = -ENOMEM;
+
+ root_inode = new_inode(sb);
+ if (!root_inode)
+ goto out;
+
+ err = read_name(root_inode, host_root_path);
+ if (err)
+ goto out_put;
+
+ err = -ENOMEM;
+ sb->s_fs_info = host_root_path;
+ sb->s_root = d_make_root(root_inode);
+ if (sb->s_root == NULL)
+ goto out;
+
+ return 0;
+
+out_put:
+ iput(root_inode);
+out:
+ return err;
+}
+
+static struct dentry *dafs_read_sb(struct file_system_type *type,
+ int flags, const char *dev_name,
+ void *data)
+{
+ if (!metag_da_enabled())
+ return ERR_PTR(-ENODEV);
+ return mount_nodev(type, flags, data, dafs_fill_sb_common);
+}
+
+static struct file_system_type dafs_type = {
+ .owner = THIS_MODULE,
+ .name = "imgdafs",
+ .mount = dafs_read_sb,
+ .kill_sb = kill_anon_super,
+ .fs_flags = 0,
+};
+MODULE_ALIAS_FS("imgdafs");
+
+static int __init init_dafs(void)
+{
+ return register_filesystem(&dafs_type);
+}
+
+static void __exit exit_dafs(void)
+{
+ unregister_filesystem(&dafs_type);
+}
+
+module_init(init_dafs)
+module_exit(exit_dafs)
+MODULE_LICENSE("GPL");
diff --git a/include/uapi/linux/magic.h b/include/uapi/linux/magic.h
index 77c60311a6c6..2487967f5e96 100644
--- a/include/uapi/linux/magic.h
+++ b/include/uapi/linux/magic.h
@@ -31,6 +31,7 @@
#define PSTOREFS_MAGIC 0x6165676C
#define EFIVARFS_MAGIC 0xde5e81e4
#define HOSTFS_SUPER_MAGIC 0x00c0ffee
+#define IMGDAFS_SUPER_MAGIC 0xdadadaf5
#define MINIX_SUPER_MAGIC 0x137F /* minix v1 fs, 14 char names */
#define MINIX_SUPER_MAGIC2 0x138F /* minix v1 fs, 30 char names */
--
1.8.1.2
--
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