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* XFS support
@ 2005-09-13 17:16 Marco Gerards
  2005-09-17 11:10 ` Marco Gerards
  0 siblings, 1 reply; 9+ messages in thread
From: Marco Gerards @ 2005-09-13 17:16 UTC (permalink / raw)
  To: grub-devel

Hi,

Today I finally had some time to work on XFS support for GRUB 2.
Because I don't have a XFS filesystem that is really used myself, I
only tested it with a small test filesystem.  If there are any
problems, I expect them to be in the aggregrate support and in support
of the larger files.

I still have to do more testing and cleaning up the code, but some
testing done by people who actually used XFS would be very useful to
me.  I just included xfs.c inline and not as a patch, making it a
patch only adds noise for someone who wants to read it.  Just replace
jfs.c or so with this file and recompile.

Soon I will do more testing and cleaning up before I commit all this.
No need to proofread this code, I know there are some ugly things so
you might do double work.

Thanks,
Marco



/* xfs.c - XFS.  */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2005  Free Software Foundation, Inc.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <grub/err.h>
#include <grub/file.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/disk.h>
#include <grub/dl.h>
#include <grub/types.h>
#include <grub/fshelp.h>

#define	XFS_INODE_EXTENTS	9

#define XFS_INODE_FORMAT_INO	1
#define XFS_INODE_FORMAT_EXT	2


struct grub_xfs_sblock
{
  grub_uint8_t magic[4];
  grub_uint32_t bsize;
  grub_uint8_t unused1[48];
  grub_uint64_t rootino;
  grub_uint8_t unused2[20];
  grub_uint32_t agsize; 
  grub_uint8_t unused3[20];
  grub_uint8_t label[12];
  grub_uint8_t log2_bsize;
} __attribute__ ((packed));

struct grub_xfs_dir_header
{
  grub_uint8_t entries;
  grub_uint8_t smallino;
  grub_uint32_t parent;
} __attribute__ ((packed));

struct grub_xfs_dir_entry
{
  grub_uint8_t len;
  grub_uint16_t offset;
  char name[1];
  /* Inode number follows, 32 bits.  */
} __attribute__ ((packed));

struct grub_xfs_dir2_entry
{
  grub_uint64_t inode;
  grub_uint8_t len;
} __attribute__ ((packed));

typedef grub_uint32_t grub_xfs_extent[4];

struct grub_xfs_inode
{
  grub_uint8_t magic[2];
  grub_uint16_t mode;
  grub_uint8_t version;
  grub_uint8_t format;
  grub_uint8_t unused2[50];
  grub_uint64_t size;
  grub_uint8_t unused3[36];
  union
  {
    char raw[156];
    struct dir
    {
      struct grub_xfs_dir_header dirhead;
      struct grub_xfs_dir_entry direntry[1];
    } dir;
    grub_xfs_extent extents[XFS_INODE_EXTENTS];
  } data __attribute__ ((packed));
} __attribute__ ((packed));

struct grub_fshelp_node
{
  struct grub_xfs_data *data;
  struct grub_xfs_inode inode;
  grub_uint64_t ino;
  int inode_read;
};

struct grub_xfs_data
{
  struct grub_xfs_sblock sblock;
  struct grub_xfs_inode *inode;
  grub_disk_t disk;
  int pos;
  int bsize;
  int agsize;
  struct grub_fshelp_node diropen;

};
\f

/* Filetype information as used in inodes.  */
#define FILETYPE_INO_MASK	0170000
#define FILETYPE_INO_REG	0100000
#define FILETYPE_INO_DIRECTORY	0040000
#define FILETYPE_INO_SYMLINK	0120000

#define GRUB_XFS_INO_INOINAG(ino) (grub_be_to_cpu64 (ino) & 0xFFFFFFFFUL)
#define GRUB_XFS_INO_AG(ino)	  (grub_be_to_cpu64 (ino) >> 32)

#define GRUB_XFS_EXTENT_OFFSET(inode,ex) \
	((grub_be_to_cpu32 ((inode)->data.extents[ex][0]) & ~(1 << 31)) << 23 \
	| grub_be_to_cpu32 ((inode)->data.extents[ex][1]) >> 9)

#define GRUB_XFS_EXTENT_BLOCK(inode,ex)  \
	((grub_uint64_t) (grub_be_to_cpu32 ((inode)->data.extents[ex][1]) \
		  	  & (~255)) << 43 \
	 | (grub_uint64_t) grub_be_to_cpu32 ((inode)->data.extents[ex][2]) << 11 \
	 | grub_be_to_cpu32 ((inode)->data.extents[ex][3]) >> 21)

#define GRUB_XFS_EXTENT_SIZE(inode,ex) \
	(grub_be_to_cpu32 ((inode)->data.extents[ex][3]) & ((1 << 20) - 1))

\f
static inline int grub_xfs_inode_block (struct grub_xfs_data *data,
					grub_uint64_t ino)
{
  int inoag = GRUB_XFS_INO_INOINAG (ino);
  int ag = GRUB_XFS_INO_AG (ino);
  int block;

  block = (inoag >> 4) + ag * data->agsize;
  block <<= 3;
  return block;
}


static inline int grub_xfs_inode_offset (grub_uint64_t ino)
{
  int inoag = GRUB_XFS_INO_INOINAG (ino);
  return (inoag & ((1 << 4) - 1)) << 8;
}


static grub_err_t
grub_xfs_read_inode (struct grub_xfs_data *data, long ino,
		     struct grub_xfs_inode *inode)
{
  int block = grub_xfs_inode_block (data, ino);
  int offset = grub_xfs_inode_offset (ino);

  /* Read the inode.  */
  if (grub_disk_read (data->disk, block, offset,
		      sizeof (struct grub_xfs_inode), (char *) inode))
    return grub_errno;

  if (grub_strncmp (inode->magic, "IN", 2))
    return grub_error (GRUB_ERR_BAD_FS, "not a correct XFS inode.\n");

  return 0;
}


static int
grub_xfs_read_block (grub_fshelp_node_t node, int fileblock)
{
  int ex;

  if (node->inode.format != XFS_INODE_FORMAT_EXT)
    {
      grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
		  "xfs does not support inode format %d yet",
		  node->inode.format);
      return 0;
    }

  /* Iterate over each extent to figure out which extent has
     the block we are looking for.  */
  for (ex = 0; ex < XFS_INODE_EXTENTS; ex++)
    {
      int start = GRUB_XFS_EXTENT_BLOCK (&node->inode, ex);
      int offset = GRUB_XFS_EXTENT_OFFSET (&node->inode, ex);
      int size = GRUB_XFS_EXTENT_SIZE (&node->inode, ex);

      if (fileblock < offset + size)
	return (fileblock - offset + start);
    }

  grub_error (GRUB_ERR_FILE_READ_ERROR,
	      "xfs block %d for inode %d is not in an extent.\n",
	      fileblock, grub_be_to_cpu64 (node->ino));
  return 0;
}


/* Read LEN bytes from the file described by DATA starting with byte
   POS.  Return the amount of read bytes in READ.  */
static grub_ssize_t
grub_xfs_read_file (grub_fshelp_node_t node,
		     void (*read_hook) (unsigned long sector,
					unsigned offset, unsigned length),
		     int pos, unsigned int len, char *buf)
{
  return grub_fshelp_read_file (node->data->disk, node, read_hook,
				pos, len, buf, grub_xfs_read_block,
				grub_be_to_cpu64 (node->inode.size),
				3/* LOG2_EXT2_BLOCK_SIZE (node->data) */);
}


static char *
grub_xfs_read_symlink (grub_fshelp_node_t node)
{
  int size = grub_be_to_cpu64 (node->inode.size);

  switch (node->inode.format)
    {
    case XFS_INODE_FORMAT_INO:
      return grub_strndup (node->inode.data.raw, size);

    case XFS_INODE_FORMAT_EXT:
      {
	char *symlink;
	grub_ssize_t numread;

	symlink = grub_malloc (size + 1);
	if (!symlink)
	  return 0;

	numread = grub_xfs_read_file (node, 0, 0, size, symlink);
	if (numread != size)
	  {
	    grub_free (symlink);
	    return 0;
	  }
	symlink[size] = '\0';
	return symlink;
      }
    }
  return 0;
}


static enum grub_fshelp_filetype
grub_xfs_mode_to_filetype (grub_uint16_t mode)
{
  if ((grub_be_to_cpu16 (mode)
       & FILETYPE_INO_MASK) == FILETYPE_INO_DIRECTORY)
    return GRUB_FSHELP_DIR;
  else if ((grub_be_to_cpu16 (mode)
	    & FILETYPE_INO_MASK) == FILETYPE_INO_SYMLINK)
    return GRUB_FSHELP_SYMLINK;
  else if ((grub_be_to_cpu16 (mode)
	    & FILETYPE_INO_MASK) == FILETYPE_INO_REG)
    return GRUB_FSHELP_REG;
  return GRUB_FSHELP_UNKNOWN;
}


static int
grub_xfs_iterate_dir (grub_fshelp_node_t dir,
		       int NESTED_FUNC_ATTR
		       (*hook) (const char *filename,
				enum grub_fshelp_filetype filetype,
				grub_fshelp_node_t node))
{
  struct grub_fshelp_node *diro = (struct grub_fshelp_node *) dir;
    
  int call_hook (grub_uint64_t ino, char *filename)
    {
      struct grub_fshelp_node *fdiro;

      fdiro = grub_malloc (sizeof (struct grub_fshelp_node));
      if (!fdiro)
	return 0;
	      
      /* The inode should be read, otherwise the filetype can
	 not be determined.  */
      fdiro->ino = ino;
      fdiro->inode_read = 1;
      fdiro->data = diro->data;
      grub_xfs_read_inode (diro->data, ino, &fdiro->inode);

      return hook (filename,
		   grub_xfs_mode_to_filetype (fdiro->inode.mode),
		   fdiro);
    }
  
  switch (diro->inode.format)
    {
    case XFS_INODE_FORMAT_INO:
      {
	struct grub_xfs_dir_entry *de = &diro->inode.data.dir.direntry[0];
	int smallino = !diro->inode.data.dir.dirhead.smallino;
	int i;
	grub_uint64_t parent;

	/* If small inode numbers are used to pack the direntry, the
	   parent inode number is small too.  */
	if (smallino)
	  parent = grub_cpu_to_be64 (grub_be_to_cpu32 (diro->inode.data.dir.dirhead.parent));
	else
	  {
	    parent = *(grub_uint64_t *) &diro->inode.data.dir.dirhead.parent;
	    /* The header is a bit bigger than usual.  */
	    de = (struct grub_xfs_dir_entry *) ((char *) de + 4);
	  }

	/* Synthesize the direntries for `.' and `..'.  */
	if (call_hook (diro->ino, "."))
	  return 1;

	if (call_hook (parent, ".."))
	  return 1;

	for (i = 0; i < diro->inode.data.dir.dirhead.entries; i++)
	  {
	    grub_uint64_t ino;
	    void *inopos = (((char *) de)
			    + sizeof (struct grub_xfs_dir_entry) + de->len - 1);

	    if (smallino)
	      ino = grub_cpu_to_be64 (grub_be_to_cpu32 (*(grub_uint32_t *) inopos));
	    else
	      ino = *(grub_uint64_t *) inopos;

	    if (call_hook (ino, de->name))
	      return 1;

	    de = ((struct grub_xfs_dir_entry *) 
		  (((char *) de)+ sizeof (struct grub_xfs_dir_entry) + de->len
		   + (smallino ? 4 : 8) - 1));
	  }
	break;
      }
      
    case XFS_INODE_FORMAT_EXT:
      {
	grub_ssize_t numread;
	char *dirblock;
	unsigned int blk;

	dirblock = grub_malloc (dir->data->bsize);
	if (!dirblock)
	  return 0;

	/* Iterate over every block the directory has.  */
	for (blk = 0;
	     blk < (grub_be_to_cpu64 (dir->inode.size) 
		    >> dir->data->sblock.log2_bsize);
	     blk++)
	  {
	    /* The header is skipped, the first direntry is stored
	       from byte 16.  */
	    int pos = 16;

	    numread = grub_xfs_read_file (dir, 0,
					  blk << dir->data->sblock.log2_bsize,
					  dir->data->bsize, dirblock);

	    /* Iterate over all entries within this block.  */
	    while (pos < dir->data->bsize - (int) sizeof (struct grub_xfs_dir2_entry))
	      {
		struct grub_xfs_dir2_entry *direntry;
		grub_uint16_t *freetag;
		char *filename;

		direntry = (struct grub_xfs_dir2_entry *) &dirblock[pos];
		freetag = (grub_uint16_t *) direntry;

		if (*freetag == 0XFFFF)
		  {
		    grub_uint16_t *skip = (grub_uint16_t *) (freetag + 1);
		    /* This entry is not used, go to the next one.  */
		    pos += *skip;

		    /* Round to 8 bytes. */
		    pos = ((pos + 8 -1 ) / 8) * 8;

		    continue;
		  }
	    
		filename = &dirblock[pos + sizeof (*direntry)];
		/* The byte after the filename is for the tag, which
		   is not used by GRUB.  So it can be overwritten.  */
		filename[direntry->len] = '\0';

		if (call_hook (direntry->inode, filename))
		  {
		    grub_free (dirblock);
		    return 1;
		  }

		pos += 8 + 1 + direntry->len + 2;
	    
		/* Round to 8 bytes. */
		pos = ((pos + 8 - 1) / 8) * 8;
	      }
	  }
	grub_free (dirblock);
	break;
      }

    default:
      grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
		  "xfs does not support inode format %d yet",
		  diro->inode.format);
    }
  return 0;
}


static struct grub_xfs_data *
grub_xfs_mount (grub_disk_t disk)
{
  struct grub_xfs_data *data = 0;

  data = grub_malloc (sizeof (struct grub_xfs_data));
  if (!data)
    return 0;

  /* Read the superblock.  */
  if (grub_disk_read (disk, 0, 0,
		      sizeof (struct grub_xfs_sblock), (char *) &data->sblock))
    goto fail;
  
  if (grub_strncmp (data->sblock.magic, "XFSB", 4))
    {
      grub_error (GRUB_ERR_BAD_FS, "not a xfs filesystem");
      goto fail;
    }

  data->diropen.data = data;
  data->diropen.ino = data->sblock.rootino;
  data->diropen.inode_read = 1;
  data->bsize = grub_cpu_to_be32 (data->sblock.bsize);
  data->agsize = grub_cpu_to_be32 (data->sblock.agsize);

  data->disk = disk;
  data->inode = &data->diropen.inode;
  data->pos = 0;

  grub_xfs_read_inode (data, data->diropen.ino, data->inode);
  
  return data;
 fail:
  
  grub_free (data);
  
  return 0;
}

\f
static grub_err_t
grub_xfs_dir (grub_device_t device, const char *path, 
	      int (*hook) (const char *filename, int dir))
{
  struct grub_xfs_data *data = 0;;
  struct grub_fshelp_node *fdiro = 0;
  
  auto int NESTED_FUNC_ATTR iterate (const char *filename,
				     enum grub_fshelp_filetype filetype,
				     grub_fshelp_node_t node);

  int NESTED_FUNC_ATTR iterate (const char *filename,
				enum grub_fshelp_filetype filetype,
				grub_fshelp_node_t node)
    {
      grub_free (node);
      
      if (filetype == GRUB_FSHELP_DIR)
	return hook (filename, 1);
      else 
	return hook (filename, 0);
      
      return 0;
    }

#ifndef GRUB_UTIL
  grub_dl_ref (my_mod);
#endif
  
  data = grub_xfs_mount (device->disk);
  if (!data)
    goto fail;
  
  grub_fshelp_find_file (path, &data->diropen, &fdiro, grub_xfs_iterate_dir,
			 grub_xfs_read_symlink, GRUB_FSHELP_DIR);
  if (grub_errno)
    goto fail;

  grub_xfs_iterate_dir (fdiro, iterate);
  
 fail:
  if (fdiro != &data->diropen)
    grub_free (fdiro);
  grub_free (data);

#ifndef GRUB_UTIL
  grub_dl_unref (my_mod);
#endif

  return grub_errno;

  return 0;
}


/* Open a file named NAME and initialize FILE.  */
static grub_err_t
grub_xfs_open (struct grub_file *file, const char *name)
{
  struct grub_xfs_data *data;
  struct grub_fshelp_node *fdiro = 0;
  
#ifndef GRUB_UTIL
  grub_dl_ref (my_mod);
#endif
  
  data = grub_xfs_mount (file->device->disk);
  if (!data)
    goto fail;
  
  grub_fshelp_find_file (name, &data->diropen, &fdiro, grub_xfs_iterate_dir,
			 grub_xfs_read_symlink, GRUB_FSHELP_REG);
  if (grub_errno)
    goto fail;
  
  if (!fdiro->inode_read)
    {
      grub_xfs_read_inode (data, fdiro->ino, &fdiro->inode);
      if (grub_errno)
	goto fail;
    }
  
  grub_memcpy (data->inode,
	       &fdiro->inode,
	       sizeof (struct grub_xfs_inode));
  grub_free (fdiro);

  file->size = grub_be_to_cpu64 (data->inode->size);
  file->data = data;
  file->offset = 0;

  return 0;

 fail:
  if (fdiro != &data->diropen)
    grub_free (fdiro);
  grub_free (data);
  
#ifndef GRUB_UTIL
  grub_dl_unref (my_mod);
#endif

  return grub_errno;
}


static grub_ssize_t
grub_xfs_read (grub_file_t file, char *buf, grub_ssize_t len)
{
  struct grub_xfs_data *data = 
    (struct grub_xfs_data *) file->data;

  return grub_xfs_read_file (&data->diropen, file->read_hook,
			      file->offset, len, buf);
}


static grub_err_t
grub_xfs_close (grub_file_t file)
{
  grub_free (file->data);

#ifndef GRUB_UTIL
  grub_dl_unref (my_mod);
#endif

  return GRUB_ERR_NONE;
}


static grub_err_t
grub_xfs_label (grub_device_t device, char **label)
{
  struct grub_xfs_data *data;
  grub_disk_t disk = device->disk;

#ifndef GRUB_UTIL
  grub_dl_ref (my_mod);
#endif

  data = grub_xfs_mount (disk);
  if (data)
    *label = grub_strndup (data->sblock.label, 12);
  else
    *label = 0;

#ifndef GRUB_UTIL
  grub_dl_unref (my_mod);
#endif

  grub_free (data);

  return grub_errno;
}

\f

static struct grub_fs grub_xfs_fs =
  {
    .name = "xfs",
    .dir = grub_xfs_dir,
    .open = grub_xfs_open,
    .read = grub_xfs_read,
    .close = grub_xfs_close,
    .label = grub_xfs_label,
    .next = 0
  };

#ifdef GRUB_UTIL
void
grub_xfs_init (void)
{
  grub_fs_register (&grub_xfs_fs);
}

void
grub_xfs_fini (void)
{
  grub_fs_unregister (&grub_xfs_fs);
}
#else /* ! GRUB_UTIL */
GRUB_MOD_INIT
{
  grub_fs_register (&grub_xfs_fs);
  my_mod = mod;
}

GRUB_MOD_FINI
{
  grub_fs_unregister (&grub_xfs_fs);
}
#endif /* ! GRUB_UTIL */




^ permalink raw reply	[flat|nested] 9+ messages in thread
* AFFS support
@ 2005-09-27 21:00 Marco Gerards
  2005-09-28 10:10 ` Marco Gerards
  0 siblings, 1 reply; 9+ messages in thread
From: Marco Gerards @ 2005-09-27 21:00 UTC (permalink / raw)
  To: grub-devel; +Cc: jaime.dias

Hi,

Because I didn't immediately want to continue working on XFS support
and because Jaime (he's CC'ed) asked me about AFFS support, I wrote
AFFS support.

It was only tested using an image I found on the internet, but I
expect it works for any AFFS filesystem.  OFS filesystems are not
supported (yet), but that should be really easy to change.  AFAIK I
just used features that are also available for OFS.

If no one sees a problem in this code and no bugs are reported this
week, I will apply AFFS support this weekend.

As I normally do with filesystems, I didn't send in a patch, but just
the code.  If you want to test it, the easiest way to do so is
replacing some filesystem (jfs.c or so) with this code.

Both the SFS (if it is just as easy to implement as AFFS, I need it
for my pegasos) and XFS filesystem are on my short term to do list.

Thanks,
Marco


/* affs.c - Amiga Fast FileSystem.  */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2005  Free Software Foundation, Inc.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <grub/err.h>
#include <grub/file.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/disk.h>
#include <grub/dl.h>
#include <grub/types.h>
#include <grub/fshelp.h>

/* The affs bootblock.  */
struct grub_affs_bblock
{
  grub_uint8_t type[3];
  grub_uint8_t flags;
  grub_uint32_t checksum;
  grub_uint32_t rootblock;
};

/* Set if the filesystem is a AFFS filesystem.  Otherwise this is an
   OFS filesystem.  */
#define GRUB_AFFS_FLAG_FFS	1

/* The affs rootblock.  */
struct grub_affs_rblock
{
  grub_uint8_t type[4];
  grub_uint8_t unused1[8];
  grub_uint32_t htsize;
  grub_uint32_t unused2;
  grub_uint32_t checksum;
  grub_uint32_t hashtable[1];
};

/* The second part of a file header block.  */
struct grub_affs_file
{
  grub_uint8_t unused1[12];
  grub_uint32_t size;
  grub_uint8_t unused2[104];
  grub_uint8_t namelen;
  grub_uint8_t name[30];
  grub_uint8_t unused3[33];
  grub_uint32_t next;
  grub_uint32_t parent;
  grub_uint32_t extension;
  grub_int32_t type;
};

/* The location of `struct grub_affs_file' relative to the end of a
   file header block.  */
#define	GRUB_AFFS_FILE_LOCATION		200

/* The offset in both the rootblock and the file header block for the
   hashtable, symlink and block pointers (all synonyms).  */
#define GRUB_AFFS_HASHTABLE_OFFSET	24
#define GRUB_AFFS_BLOCKPTR_OFFSET	24
#define GRUB_AFFS_SYMLINK_OFFSET	24

#define GRUB_AFFS_SYMLINK_SIZE(blocksize) ((blocksize) - 225)

#define GRUB_AFFS_FILETYPE_DIR		-3
#define GRUB_AFFS_FILETYPE_REG		2
#define GRUB_AFFS_FILETYPE_SYMLINK	3
\f

struct grub_fshelp_node
{
  struct grub_affs_data *data;
  int block;
  int size;
  int parent;
};

/* Information about a "mounted" affs filesystem.  */
struct grub_affs_data
{
  struct grub_affs_bblock bblock;
  struct grub_fshelp_node diropen;
  grub_disk_t disk;

  /* Blocksize in sectors.  */
  int blocksize;

  /* The number of entries in the hashtable.  */
  int htsize;
};

#ifndef GRUB_UTIL
static grub_dl_t my_mod;
#endif

\f
static int
grub_affs_read_block (grub_fshelp_node_t node, int fileblock)
{
  int links;
  grub_uint32_t pos;
  int block = node->block;
  struct grub_affs_file file;
  struct grub_affs_data *data = node->data;

  /* Find the block that points to the fileblock we are looking up by
     following the chain until the right table is reached.  */
  for (links = fileblock / (data->htsize); links; links--)
    {
      grub_disk_read (data->disk, block + data->blocksize - 1,
		      data->blocksize * (GRUB_DISK_SECTOR_SIZE
					 - GRUB_AFFS_FILE_LOCATION),
		      sizeof (file), (char *) &file);
      if (grub_errno)
	return 0;
	  
      block = grub_be_to_cpu32 (file.extension);
    }

  /* Translate the fileblock to the block within the right table.  */
  fileblock = fileblock % (data->htsize);
  grub_disk_read (data->disk, block,
		  GRUB_AFFS_BLOCKPTR_OFFSET
		  + (data->htsize - fileblock - 1) * sizeof (pos),
		  sizeof (pos), (char *) &pos);
  if (grub_errno)
    return 0;
  
  return grub_be_to_cpu32 (pos);
}


/* Read LEN bytes from the file described by DATA starting with byte
   POS.  Return the amount of read bytes in READ.  */
static grub_ssize_t
grub_affs_read_file (grub_fshelp_node_t node,
		     void (*read_hook) (unsigned long sector,
					unsigned offset, unsigned length),
		     int pos, unsigned int len, char *buf)
{
  return grub_fshelp_read_file (node->data->disk, node, read_hook,
				pos, len, buf, grub_affs_read_block,
				node->size, 0);
}


static struct grub_affs_data *
grub_affs_mount (grub_disk_t disk)
{
  struct grub_affs_data *data;
  grub_uint32_t *rootblock = 0;
  struct grub_affs_rblock *rblock;

  int checksum = 0;
  int checksumr = 0;
  int blocksize = 0;

  data = grub_malloc (sizeof (struct grub_affs_data));
  if (!data)
    return 0;

  /* Read the bootblock.  */
  grub_disk_read (disk, 0, 0, sizeof (struct grub_affs_bblock),
		  (char *) &data->bblock);
  if (grub_errno)
    goto fail;

  /* Make sure this is an affs filesystem.  */
  if (grub_strncmp (data->bblock.type, "DOS", 3))
    {
      grub_error (GRUB_ERR_BAD_FS, "not an affs filesystem");
      goto fail;
    }

  /* Test if the filesystem is a OFS filesystem.  */
  if (! (data->bblock.flags & GRUB_AFFS_FLAG_FFS))
    {
      grub_error (GRUB_ERR_BAD_FS, "ofs not yet supported");
      goto fail;
    }

  /* Read the bootblock.  */
  grub_disk_read (disk, 0, 0, sizeof (struct grub_affs_bblock),
		  (char *) &data->bblock);
  if (grub_errno)
    goto fail;

  /* No sane person uses more than 8KB for a block.  At least I hope
     for that person because in that case this won't work.  */
  rootblock = grub_malloc (GRUB_DISK_SECTOR_SIZE * 16);
  if (!rootblock)
    goto fail;

  rblock = (struct grub_affs_rblock *) rootblock;

  /* Read the rootblock.  */
  grub_disk_read (disk, (disk->total_sectors >> 1) + blocksize, 0,
		  GRUB_DISK_SECTOR_SIZE * 16, (char *) rootblock);
  if (grub_errno)
    goto fail;

  /* The filesystem blocksize is not stored anywhere in the filesystem
     itself.  One way to determine it is reading blocks for the
     rootblock until the checksum is correct.  */
  checksumr = grub_be_to_cpu32 (rblock->checksum);
  rblock->checksum = 0;
  for (blocksize = 0; blocksize < 8; blocksize++)
    {
      grub_uint32_t *currblock = rootblock + GRUB_DISK_SECTOR_SIZE * blocksize;
      unsigned int i;

      for (i = 0; i < GRUB_DISK_SECTOR_SIZE / sizeof (*currblock); i++)
	checksum += grub_be_to_cpu32 (currblock[i]);

      if (checksumr == -checksum)
	break;
    }
  if (-checksum != checksumr)
    {
      grub_error (GRUB_ERR_BAD_FS, "affs blocksize could not be determined");
      goto fail;
    }
  blocksize++;

  data->blocksize = blocksize;
  data->disk = disk;
  data->htsize = grub_be_to_cpu32 (rblock->htsize);
  data->diropen.data = data;
  data->diropen.block = (disk->total_sectors >> 1);

  grub_free (rootblock);

  return data;

 fail:
  grub_free (data);
  grub_free (rootblock);
  return 0;
}


static char *
grub_affs_read_symlink (grub_fshelp_node_t node)
{
  struct grub_affs_data *data = node->data;
  char *symlink;

  symlink = grub_malloc (GRUB_AFFS_SYMLINK_SIZE (data->blocksize));
  if (!symlink)
    return 0;

  grub_disk_read (data->disk, node->block, GRUB_AFFS_SYMLINK_OFFSET,
		  GRUB_AFFS_SYMLINK_SIZE (data->blocksize), symlink);
  if (grub_errno)
    {
      grub_free (symlink);
      return 0;
    }
  grub_printf ("Symlink: `%s'\n", symlink);
  return symlink;
}


static int
grub_affs_iterate_dir (grub_fshelp_node_t dir,
		       int NESTED_FUNC_ATTR
		       (*hook) (const char *filename,
				enum grub_fshelp_filetype filetype,
				grub_fshelp_node_t node))
{
  int i;
  struct grub_affs_file file;
  struct grub_fshelp_node *node = 0;
  struct grub_affs_data *data = dir->data;
  grub_uint32_t *hashtable;

  auto int NESTED_FUNC_ATTR grub_affs_create_node (const char *name, int block,
						   int size, int type);

  int NESTED_FUNC_ATTR grub_affs_create_node (const char *name, int block,
					      int size, int type)
    {
      node = grub_malloc (sizeof (*node));
      if (!node)
	{
	  grub_free (hashtable);
	  return 1;
	}

      node->data = data;
      node->size = size;
      node->block = block;
      node->parent = grub_be_to_cpu32 (file.parent);

      if (hook (name, type, node))
	{
	  grub_free (hashtable);
	  return 1;
	}
      return 0;
    }

  hashtable = grub_malloc (data->htsize * sizeof (*hashtable));
  if (!hashtable)
    return 1;

  grub_disk_read (data->disk, dir->block, GRUB_AFFS_HASHTABLE_OFFSET,
		  data->htsize * sizeof (*hashtable), (char *) hashtable);
  if (grub_errno)
    goto fail;

  /* Create the directory entries for `.' and `..'.  */
  if (grub_affs_create_node (".", dir->block, dir->size, GRUB_FSHELP_DIR))
    return 1;
  if (grub_affs_create_node ("..", dir->parent ? dir->parent : dir->block,
			     dir->size, GRUB_FSHELP_DIR))
    return 1;

  for (i = 0; i < data->htsize; i++)
    {
      enum grub_fshelp_filetype type;
      grub_uint64_t next;

      if (!hashtable[i])
	continue;

      /* Every entry in the hashtable can be chained.  Read the entire
	 chain.  */
      next = grub_be_to_cpu32 (hashtable[i]);

      while (next)
	{
	  grub_disk_read (data->disk, next + data->blocksize - 1,
			  data->blocksize * GRUB_DISK_SECTOR_SIZE
			  - GRUB_AFFS_FILE_LOCATION,
			  sizeof (file), (char *) &file);
	  if (grub_errno)
	    goto fail;
	  
	  file.name[file.namelen] = '\0';

	  if ((int) grub_be_to_cpu32 (file.type) == GRUB_AFFS_FILETYPE_DIR)
	    type = GRUB_FSHELP_REG;
	  else if (grub_be_to_cpu32 (file.type) == GRUB_AFFS_FILETYPE_REG)
	    type = GRUB_FSHELP_DIR;
	  else if (grub_be_to_cpu32 (file.type) == GRUB_AFFS_FILETYPE_SYMLINK)
	    type = GRUB_FSHELP_SYMLINK;
	  else
	    type = GRUB_FSHELP_UNKNOWN;

	  if (grub_affs_create_node (file.name, next,
				     grub_be_to_cpu32 (file.size), type))
	    return 1;

	  next = grub_be_to_cpu32 (file.next);
	}      
    }

  grub_free (hashtable);
  return 0;

 fail:
  grub_free (node);
  grub_free (hashtable);
  return 1;
}


/* Open a file named NAME and initialize FILE.  */
static grub_err_t
grub_affs_open (struct grub_file *file, const char *name)
{
  struct grub_affs_data *data;
  struct grub_fshelp_node *fdiro = 0;
  
#ifndef GRUB_UTIL
  grub_dl_ref (my_mod);
#endif
  
  data = grub_affs_mount (file->device->disk);
  if (!data)
    goto fail;
  
  grub_fshelp_find_file (name, &data->diropen, &fdiro, grub_affs_iterate_dir,
			 grub_affs_read_symlink, GRUB_FSHELP_REG);
  if (grub_errno)
    goto fail;
  
  file->size = fdiro->size;
  data->diropen = *fdiro;
  grub_free (fdiro);

  file->data = data;
  file->offset = 0;

  return 0;

 fail:
  if (data && fdiro != &data->diropen)
    grub_free (fdiro);
  grub_free (data);
  
#ifndef GRUB_UTIL
  grub_dl_unref (my_mod);
#endif

  return grub_errno;
}


static grub_err_t
grub_affs_close (grub_file_t file)
{
  grub_free (file->data);

#ifndef GRUB_UTIL
  grub_dl_unref (my_mod);
#endif

  return GRUB_ERR_NONE;
}


/* Read LEN bytes data from FILE into BUF.  */
static grub_ssize_t
grub_affs_read (grub_file_t file, char *buf, grub_ssize_t len)
{
  struct grub_affs_data *data = 
    (struct grub_affs_data *) file->data;

  int size = grub_affs_read_file (&data->diropen, file->read_hook,
			      file->offset, len, buf);

  return size;
}


static grub_err_t
grub_affs_dir (grub_device_t device, const char *path, 
	       int (*hook) (const char *filename, int dir))
{
  struct grub_affs_data *data = 0;
  struct grub_fshelp_node *fdiro = 0;
  
  auto int NESTED_FUNC_ATTR iterate (const char *filename,
				     enum grub_fshelp_filetype filetype,
				     grub_fshelp_node_t node);

  int NESTED_FUNC_ATTR iterate (const char *filename,
				enum grub_fshelp_filetype filetype,
				grub_fshelp_node_t node)
    {
      grub_free (node);
      
      if (filetype == GRUB_FSHELP_DIR)
	return hook (filename, 1);
      else 
	return hook (filename, 0);
      
      return 0;
    }

#ifndef GRUB_UTIL
  grub_dl_ref (my_mod);
#endif
  
  data = grub_affs_mount (device->disk);
  if (!data)
    goto fail;
  
  grub_fshelp_find_file (path, &data->diropen, &fdiro, grub_affs_iterate_dir,
			 grub_affs_read_symlink, GRUB_FSHELP_DIR);
  if (grub_errno)
    goto fail;

  grub_affs_iterate_dir (fdiro, iterate);
  
 fail:
  if (data && fdiro != &data->diropen)
    grub_free (fdiro);
  grub_free (data);

#ifndef GRUB_UTIL
  grub_dl_unref (my_mod);
#endif

  return grub_errno;
}


static grub_err_t
grub_affs_label (grub_device_t device, char **label)
{
  struct grub_affs_data *data;
  struct grub_affs_file file;
  grub_disk_t disk = device->disk;

#ifndef GRUB_UTIL
  grub_dl_ref (my_mod);
#endif

  data = grub_affs_mount (disk);
  if (data)
    {
      /* The rootblock maps quite well on a file header block, it's
	 something we can use here.  */
      grub_disk_read (data->disk, disk->total_sectors >> 1,
		      data->blocksize * (GRUB_DISK_SECTOR_SIZE
					 - GRUB_AFFS_FILE_LOCATION),
		      sizeof (file), (char *) &file);
      if (grub_errno)
	return 0;

      *label = grub_strndup (file.name, file.namelen);
    }
  else
    *label = 0;

#ifndef GRUB_UTIL
  grub_dl_unref (my_mod);
#endif

  grub_free (data);

  return grub_errno;
}

\f
static struct grub_fs grub_affs_fs =
  {
    .name = "affs",
    .dir = grub_affs_dir,
    .open = grub_affs_open,
    .read = grub_affs_read,
    .close = grub_affs_close,
    .label = grub_affs_label,
    .next = 0
  };

#ifdef GRUB_UTIL
void
grub_affs_init (void)
{
  grub_fs_register (&grub_affs_fs);
}

void
grub_affs_fini (void)
{
  grub_fs_unregister (&grub_affs_fs);
}
#else /* ! GRUB_UTIL */
GRUB_MOD_INIT
{
  grub_fs_register (&grub_affs_fs);
  my_mod = mod;
}

GRUB_MOD_FINI
{
  grub_fs_unregister (&grub_affs_fs);
}
#endif /* ! GRUB_UTIL */




^ permalink raw reply	[flat|nested] 9+ messages in thread
end of thread, other threads:[~2005-10-15 17:30 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2005-09-13 17:16 XFS support Marco Gerards
2005-09-17 11:10 ` Marco Gerards
2005-09-18 17:17   ` Yoshinori K. Okuji
2005-09-18 18:03     ` Marco Gerards
2005-09-19 18:55       ` Yoshinori K. Okuji
  -- strict thread matches above, loose matches on Subject: below --
2005-09-27 21:00 AFFS support Marco Gerards
2005-09-28 10:10 ` Marco Gerards
2005-09-28 23:12   ` Yoshinori K. Okuji
2005-10-15  9:28     ` XFS support Yoshinori K. Okuji
2005-10-15 11:11       ` Marco Gerards
2005-10-15 11:41         ` Yoshinori K. Okuji
2005-10-15 17:30       ` Yoshinori K. Okuji

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