[grub2.git] / fs / xfs.c

/* 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
#define XFS_INODE_FORMAT_BTREE	3


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;
  grub_uint8_t unused4[2];
  grub_uint8_t log2_inop;
  grub_uint8_t log2_agblk;
} __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_xfs_dirblock_tail
{
  grub_uint32_t leaf_count;
  grub_uint32_t leaf_stale;
} __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;

};

#ifndef GRUB_UTIL
static grub_dl_t my_mod;
#endif

\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_AGBITS(data)		\
  ((data)->sblock.log2_agblk + (data)->sblock.log2_inop)
#define GRUB_XFS_INO_INOINAG(data, ino)		\
  (grub_be_to_cpu64 (ino) & ((1 << GRUB_XFS_INO_AGBITS (data)) - 1))
#define GRUB_XFS_INO_AG(data,ino)		\
  (grub_be_to_cpu64 (ino) >> GRUB_XFS_INO_AGBITS (data))

#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))

#define GRUB_XFS_ROUND_TO_DIRENT(pos)	((((pos) + 8 - 1) / 8) * 8)
#define GRUB_XFS_NEXT_DIRENT(pos,len)		\
  (pos) + GRUB_XFS_ROUND_TO_DIRENT (8 + 1 + len + 2)
\f
static inline int
grub_xfs_inode_block (struct grub_xfs_data *data,
		      grub_uint64_t ino)
{
  long long int inoinag = GRUB_XFS_INO_INOINAG (data, ino);
  long long ag = GRUB_XFS_INO_AG (data, ino);
  long long block;

  block = (inoinag >> 4) + ag * data->agsize;
  block <<= (data->sblock.log2_bsize - GRUB_DISK_SECTOR_BITS);
  return block;
}


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


static grub_err_t
grub_xfs_read_inode (struct grub_xfs_data *data, grub_uint64_t ino,
		     struct grub_xfs_inode *inode)
{
  int block = grub_xfs_inode_block (data, ino);
  int offset = grub_xfs_inode_offset (data, 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++)
    {
      grub_uint64_t 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);

      unsigned int ag = start >> node->data->sblock.log2_agblk;
      unsigned int block = start & ((1 << node->data->sblock.log2_agblk) - 1);

      if (fileblock < offset + size)
	return (fileblock - offset + block) + ag * node->data->agsize;
    }

  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),
				node->data->sblock.log2_bsize
				- GRUB_DISK_SECTOR_BITS);
}


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;
  auto int call_hook (grub_uint64_t ino, char *filename);
    
  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_be_to_cpu32 (diro->inode.data.dir.dirhead.parent);
	    parent = grub_cpu_to_be64 (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);
	    char name[de->len + 1];
	    
	    if (smallino)
	      {
		ino = grub_be_to_cpu32 (*(grub_uint32_t *) inopos);
		ino = grub_cpu_to_be64 (ino);
	      }
	    else
	      ino = *(grub_uint64_t *) inopos;

	    grub_memcpy (name, de->name, de->len);
	    name[de->len] = '\0';
	    if (call_hook (ino, name))
	      return 1;

	    de = ((struct grub_xfs_dir_entry *) 
		  (((char *) de)+ sizeof (struct grub_xfs_dir_entry) + de->len
		   + ((smallino ? sizeof (grub_uint32_t)
		       : sizeof (grub_uint64_t))) - 1));
	  }
	break;
      }

    case XFS_INODE_FORMAT_BTREE:
    case XFS_INODE_FORMAT_EXT:
      {
	grub_ssize_t numread;
	char *dirblock;
	grub_uint64_t 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;
	    int entries;
	    int tail_start = (dir->data->bsize
			      - sizeof (struct grub_xfs_dirblock_tail));

	    struct grub_xfs_dirblock_tail *tail;
	    tail = (struct grub_xfs_dirblock_tail *) &dirblock[tail_start];

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

	    entries = (grub_be_to_cpu32 (tail->leaf_count)
		       - grub_be_to_cpu32 (tail->leaf_stale));

	    /* 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 += grub_be_to_cpu16 (*skip);

		    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;
		  }

		/* Check if last direntry in this block is
		   reached.  */
		entries--;
		if (!entries)
		  break;

		/* Select the next directory entry.  */
		pos = GRUB_XFS_NEXT_DIRENT (pos, direntry->len);
		pos = GRUB_XFS_ROUND_TO_DIRENT (pos);
	      }
	  }
	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_be_to_cpu32 (data->sblock.bsize);
  data->agsize = grub_be_to_cpu32 (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
  };

GRUB_MOD_INIT(xfs)
{
  grub_fs_register (&grub_xfs_fs);
#ifndef GRUB_UTIL
  my_mod = mod;
#endif
}

GRUB_MOD_FINI(xfs)
{
  grub_fs_unregister (&grub_xfs_fs);
}
Commit	Line	Data
b2499b29	1	/* xfs.c - XFS. */
	2	/*
	3	* GRUB -- GRand Unified Bootloader
	4	* Copyright (C) 2005 Free Software Foundation, Inc.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	19	*/
	20
	21	#include <grub/err.h>
	22	#include <grub/file.h>
	23	#include <grub/mm.h>
	24	#include <grub/misc.h>
	25	#include <grub/disk.h>
	26	#include <grub/dl.h>
	27	#include <grub/types.h>
	28	#include <grub/fshelp.h>
	29
	30	#define XFS_INODE_EXTENTS 9
	31
	32	#define XFS_INODE_FORMAT_INO 1
	33	#define XFS_INODE_FORMAT_EXT 2
	34	#define XFS_INODE_FORMAT_BTREE 3
	35
	36
	37	struct grub_xfs_sblock
	38	{
	39	grub_uint8_t magic[4];
	40	grub_uint32_t bsize;
	41	grub_uint8_t unused1[48];
	42	grub_uint64_t rootino;
	43	grub_uint8_t unused2[20];
	44	grub_uint32_t agsize;
	45	grub_uint8_t unused3[20];
	46	grub_uint8_t label[12];
	47	grub_uint8_t log2_bsize;
	48	grub_uint8_t unused4[2];
	49	grub_uint8_t log2_inop;
	50	grub_uint8_t log2_agblk;
	51	} __attribute__ ((packed));
	52
	53	struct grub_xfs_dir_header
	54	{
	55	grub_uint8_t entries;
	56	grub_uint8_t smallino;
	57	grub_uint32_t parent;
	58	} __attribute__ ((packed));
	59
	60	struct grub_xfs_dir_entry
	61	{
	62	grub_uint8_t len;
	63	grub_uint16_t offset;
	64	char name[1];
65	/* Inode number follows, 32 bits. */
66	} __attribute__ ((packed));
67
68	struct grub_xfs_dir2_entry
69	{
70	grub_uint64_t inode;
71	grub_uint8_t len;
72	} __attribute__ ((packed));
73
74	typedef grub_uint32_t grub_xfs_extent[4];
75
76	struct grub_xfs_inode
77	{
78	grub_uint8_t magic[2];
79	grub_uint16_t mode;
80	grub_uint8_t version;
81	grub_uint8_t format;
82	grub_uint8_t unused2[50];
83	grub_uint64_t size;
84	grub_uint8_t unused3[36];
85	union
86	{
87	char raw[156];
88	struct dir
89	{
90	struct grub_xfs_dir_header dirhead;
91	struct grub_xfs_dir_entry direntry[1];
92	} dir;
93	grub_xfs_extent extents[XFS_INODE_EXTENTS];
94	} data __attribute__ ((packed));
95	} __attribute__ ((packed));
96
97	struct grub_xfs_dirblock_tail
98	{
99	grub_uint32_t leaf_count;
100	grub_uint32_t leaf_stale;
101	} __attribute__ ((packed));
102
103	struct grub_fshelp_node
104	{
105	struct grub_xfs_data *data;
106	struct grub_xfs_inode inode;
107	grub_uint64_t ino;
108	int inode_read;
109	};
110
111	struct grub_xfs_data
112	{
113	struct grub_xfs_sblock sblock;
114	struct grub_xfs_inode *inode;
115	grub_disk_t disk;
116	int pos;
117	int bsize;
118	int agsize;
119	struct grub_fshelp_node diropen;
120
121	};
b4093103	122
	123	#ifndef GRUB_UTIL
	124	static grub_dl_t my_mod;
	125	#endif
	126
b2499b29	127	\f
	128
	129	/* Filetype information as used in inodes. */
	130	#define FILETYPE_INO_MASK 0170000
	131	#define FILETYPE_INO_REG 0100000
	132	#define FILETYPE_INO_DIRECTORY 0040000
	133	#define FILETYPE_INO_SYMLINK 0120000
	134
	135	#define GRUB_XFS_INO_AGBITS(data) \
	136	((data)->sblock.log2_agblk + (data)->sblock.log2_inop)
	137	#define GRUB_XFS_INO_INOINAG(data, ino) \
	138	(grub_be_to_cpu64 (ino) & ((1 << GRUB_XFS_INO_AGBITS (data)) - 1))
	139	#define GRUB_XFS_INO_AG(data,ino) \
	140	(grub_be_to_cpu64 (ino) >> GRUB_XFS_INO_AGBITS (data))
	141
	142	#define GRUB_XFS_EXTENT_OFFSET(inode,ex) \
	143	((grub_be_to_cpu32 ((inode)->data.extents[ex][0]) & ~(1 << 31)) << 23 \
	144	\| grub_be_to_cpu32 ((inode)->data.extents[ex][1]) >> 9)
	145
	146	#define GRUB_XFS_EXTENT_BLOCK(inode,ex) \
	147	((grub_uint64_t) (grub_be_to_cpu32 ((inode)->data.extents[ex][1]) \
	148	& (~255)) << 43 \
	149	\| (grub_uint64_t) grub_be_to_cpu32 ((inode)->data.extents[ex][2]) << 11 \
	150	\| grub_be_to_cpu32 ((inode)->data.extents[ex][3]) >> 21)
	151
	152	#define GRUB_XFS_EXTENT_SIZE(inode,ex) \
	153	(grub_be_to_cpu32 ((inode)->data.extents[ex][3]) & ((1 << 20) - 1))
	154
	155	#define GRUB_XFS_ROUND_TO_DIRENT(pos) ((((pos) + 8 - 1) / 8) * 8)
	156	#define GRUB_XFS_NEXT_DIRENT(pos,len) \
	157	(pos) + GRUB_XFS_ROUND_TO_DIRENT (8 + 1 + len + 2)
	158	\f
688e5699	159	static inline int
	160	grub_xfs_inode_block (struct grub_xfs_data *data,
	161	grub_uint64_t ino)
b2499b29	162	{
	163	long long int inoinag = GRUB_XFS_INO_INOINAG (data, ino);
	164	long long ag = GRUB_XFS_INO_AG (data, ino);
	165	long long block;
	166
	167	block = (inoinag >> 4) + ag * data->agsize;
	168	block <<= (data->sblock.log2_bsize - GRUB_DISK_SECTOR_BITS);
	169	return block;
	170	}
	171
	172
688e5699	173	static inline int
	174	grub_xfs_inode_offset (struct grub_xfs_data *data,
	175	grub_uint64_t ino)
b2499b29	176	{
	177	int inoag = GRUB_XFS_INO_INOINAG (data, ino);
	178	return (inoag & ((1 << 4) - 1)) << 8;
	179	}
	180
	181
	182	static grub_err_t
	183	grub_xfs_read_inode (struct grub_xfs_data *data, grub_uint64_t ino,
	184	struct grub_xfs_inode *inode)
	185	{
	186	int block = grub_xfs_inode_block (data, ino);
	187	int offset = grub_xfs_inode_offset (data, ino);
	188
	189	/* Read the inode. */
	190	if (grub_disk_read (data->disk, block, offset,
	191	sizeof (struct grub_xfs_inode), (char *) inode))
	192	return grub_errno;
	193
	194	if (grub_strncmp (inode->magic, "IN", 2))
	195	return grub_error (GRUB_ERR_BAD_FS, "not a correct XFS inode.\n");
	196
	197	return 0;
	198	}
	199
	200
	201	static int
	202	grub_xfs_read_block (grub_fshelp_node_t node, int fileblock)
	203	{
	204	int ex;
	205
	206	if (node->inode.format != XFS_INODE_FORMAT_EXT)
	207	{
	208	grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
	209	"xfs does not support inode format %d yet",
	210	node->inode.format);
	211	return 0;
	212	}
	213
	214	/* Iterate over each extent to figure out which extent has
	215	the block we are looking for. */
	216	for (ex = 0; ex < XFS_INODE_EXTENTS; ex++)
	217	{
	218	grub_uint64_t start = GRUB_XFS_EXTENT_BLOCK (&node->inode, ex);
	219	int offset = GRUB_XFS_EXTENT_OFFSET (&node->inode, ex);
	220	int size = GRUB_XFS_EXTENT_SIZE (&node->inode, ex);
	221
	222	unsigned int ag = start >> node->data->sblock.log2_agblk;
	223	unsigned int block = start & ((1 << node->data->sblock.log2_agblk) - 1);
	224
	225	if (fileblock < offset + size)
	226	return (fileblock - offset + block) + ag * node->data->agsize;
	227	}
	228
	229	grub_error (GRUB_ERR_FILE_READ_ERROR,
	230	"xfs block %d for inode %d is not in an extent.\n",
	231	fileblock, grub_be_to_cpu64 (node->ino));
	232	return 0;
	233	}
	234
	235
	236	/* Read LEN bytes from the file described by DATA starting with byte
	237	POS. Return the amount of read bytes in READ. */
	238	static grub_ssize_t
	239	grub_xfs_read_file (grub_fshelp_node_t node,
240	void (*read_hook) (unsigned long sector,
241	unsigned offset, unsigned length),
242	int pos, unsigned int len, char *buf)
243	{
244	return grub_fshelp_read_file (node->data->disk, node, read_hook,
245	pos, len, buf, grub_xfs_read_block,
246	grub_be_to_cpu64 (node->inode.size),
247	node->data->sblock.log2_bsize
248	- GRUB_DISK_SECTOR_BITS);
249	}
250
251
252	static char *
253	grub_xfs_read_symlink (grub_fshelp_node_t node)
254	{
255	int size = grub_be_to_cpu64 (node->inode.size);
256
257	switch (node->inode.format)
258	{
259	case XFS_INODE_FORMAT_INO:
260	return grub_strndup (node->inode.data.raw, size);
261
262	case XFS_INODE_FORMAT_EXT:
263	{
264	char *symlink;
265	grub_ssize_t numread;
266
267	symlink = grub_malloc (size + 1);
268	if (!symlink)
269	return 0;
270
271	numread = grub_xfs_read_file (node, 0, 0, size, symlink);
272	if (numread != size)
273	{
274	grub_free (symlink);
275	return 0;
276	}
277	symlink[size] = '\0';
278	return symlink;
279	}
280	}
281
282	return 0;
283	}
284
285
286	static enum grub_fshelp_filetype
287	grub_xfs_mode_to_filetype (grub_uint16_t mode)
288	{
289	if ((grub_be_to_cpu16 (mode)
290	& FILETYPE_INO_MASK) == FILETYPE_INO_DIRECTORY)
291	return GRUB_FSHELP_DIR;
292	else if ((grub_be_to_cpu16 (mode)
293	& FILETYPE_INO_MASK) == FILETYPE_INO_SYMLINK)
294	return GRUB_FSHELP_SYMLINK;
295	else if ((grub_be_to_cpu16 (mode)
296	& FILETYPE_INO_MASK) == FILETYPE_INO_REG)
297	return GRUB_FSHELP_REG;
298	return GRUB_FSHELP_UNKNOWN;
299	}
300
301
302	static int
303	grub_xfs_iterate_dir (grub_fshelp_node_t dir,
304	int NESTED_FUNC_ATTR
305	(hook) (const char filename,
306	enum grub_fshelp_filetype filetype,
307	grub_fshelp_node_t node))
308	{
309	struct grub_fshelp_node diro = (struct grub_fshelp_node ) dir;
b4093103	310	auto int call_hook (grub_uint64_t ino, char *filename);
b2499b29	311
	312	int call_hook (grub_uint64_t ino, char *filename)
	313	{
	314	struct grub_fshelp_node *fdiro;
	315
	316	fdiro = grub_malloc (sizeof (struct grub_fshelp_node));
	317	if (!fdiro)
	318	return 0;
	319
	320	/* The inode should be read, otherwise the filetype can
	321	not be determined. */
	322	fdiro->ino = ino;
	323	fdiro->inode_read = 1;
	324	fdiro->data = diro->data;
	325	grub_xfs_read_inode (diro->data, ino, &fdiro->inode);
	326
	327	return hook (filename,
	328	grub_xfs_mode_to_filetype (fdiro->inode.mode),
	329	fdiro);
	330	}
	331
	332	switch (diro->inode.format)
	333	{
	334	case XFS_INODE_FORMAT_INO:
	335	{
	336	struct grub_xfs_dir_entry *de = &diro->inode.data.dir.direntry[0];
	337	int smallino = !diro->inode.data.dir.dirhead.smallino;
	338	int i;
	339	grub_uint64_t parent;
	340
	341	/* If small inode numbers are used to pack the direntry, the
	342	parent inode number is small too. */
	343	if (smallino)
	344	{
	345	parent = grub_be_to_cpu32 (diro->inode.data.dir.dirhead.parent);
	346	parent = grub_cpu_to_be64 (parent);
	347	}
	348	else
	349	{
	350	parent = (grub_uint64_t ) &diro->inode.data.dir.dirhead.parent;
	351	/* The header is a bit bigger than usual. */
	352	de = (struct grub_xfs_dir_entry ) ((char ) de + 4);
	353	}
	354
	355	/* Synthesize the direntries for `.' and `..'. */
	356	if (call_hook (diro->ino, "."))
	357	return 1;
	358
	359	if (call_hook (parent, ".."))
	360	return 1;
	361
	362	for (i = 0; i < diro->inode.data.dir.dirhead.entries; i++)
	363	{
	364	grub_uint64_t ino;
	365	void inopos = (((char ) de)
688e5699	366	+ sizeof (struct grub_xfs_dir_entry)
	367	+ de->len - 1);
	368	char name[de->len + 1];
	369
b2499b29	370	if (smallino)
	371	{
	372	ino = grub_be_to_cpu32 ((grub_uint32_t ) inopos);
	373	ino = grub_cpu_to_be64 (ino);
	374	}
	375	else
	376	ino = (grub_uint64_t ) inopos;
	377
688e5699	378	grub_memcpy (name, de->name, de->len);
	379	name[de->len] = '\0';
	380	if (call_hook (ino, name))
b2499b29	381	return 1;
	382
	383	de = ((struct grub_xfs_dir_entry *)
	384	(((char *) de)+ sizeof (struct grub_xfs_dir_entry) + de->len
047b67e0	385	+ ((smallino ? sizeof (grub_uint32_t)
047b67e0	386	: sizeof (grub_uint64_t))) - 1));
b2499b29	387	}
	388	break;
	389	}
	390
	391	case XFS_INODE_FORMAT_BTREE:
	392	case XFS_INODE_FORMAT_EXT:
	393	{
	394	grub_ssize_t numread;
	395	char *dirblock;
688e5699	396	grub_uint64_t blk;
b2499b29	397
b2499b29	398	dirblock = grub_malloc (dir->data->bsize);
688e5699	399	if (! dirblock)
b2499b29	400	return 0;
	401
	402	/* Iterate over every block the directory has. */
	403	for (blk = 0;
	404	blk < (grub_be_to_cpu64 (dir->inode.size)
	405	>> dir->data->sblock.log2_bsize);
	406	blk++)
	407	{
	408	/* The header is skipped, the first direntry is stored
	409	from byte 16. */
	410	int pos = 16;
	411	int entries;
	412	int tail_start = (dir->data->bsize
	413	- sizeof (struct grub_xfs_dirblock_tail));
	414
	415	struct grub_xfs_dirblock_tail *tail;
	416	tail = (struct grub_xfs_dirblock_tail *) &dirblock[tail_start];
	417
	418	numread = grub_xfs_read_file (dir, 0,
	419	blk << dir->data->sblock.log2_bsize,
	420	dir->data->bsize, dirblock);
6fa1251a	421	if (numread != dir->data->bsize)
6fa1251a	422	return 0;
b2499b29	423
	424	entries = (grub_be_to_cpu32 (tail->leaf_count)
	425	- grub_be_to_cpu32 (tail->leaf_stale));
	426
	427	/* Iterate over all entries within this block. */
	428	while (pos < (dir->data->bsize
	429	- (int) sizeof (struct grub_xfs_dir2_entry)))
	430	{
	431	struct grub_xfs_dir2_entry *direntry;
	432	grub_uint16_t *freetag;
	433	char *filename;
	434
	435	direntry = (struct grub_xfs_dir2_entry *) &dirblock[pos];
	436	freetag = (grub_uint16_t *) direntry;
	437
	438	if (*freetag == 0XFFFF)
	439	{
	440	grub_uint16_t skip = (grub_uint16_t ) (freetag + 1);
	441
	442	/* This entry is not used, go to the next one. */
	443	pos += grub_be_to_cpu16 (*skip);
	444
	445	continue;
	446	}
	447
	448	filename = &dirblock[pos + sizeof (*direntry)];
	449	/* The byte after the filename is for the tag, which
	450	is not used by GRUB. So it can be overwritten. */
	451	filename[direntry->len] = '\0';
	452
	453	if (call_hook (direntry->inode, filename))
	454	{
	455	grub_free (dirblock);
	456	return 1;
	457	}
	458
	459	/* Check if last direntry in this block is
	460	reached. */
	461	entries--;
	462	if (!entries)
	463	break;
	464
	465	/* Select the next directory entry. */
	466	pos = GRUB_XFS_NEXT_DIRENT (pos, direntry->len);
	467	pos = GRUB_XFS_ROUND_TO_DIRENT (pos);
	468	}
	469	}
	470	grub_free (dirblock);
	471	break;
	472	}
	473
	474	default:
	475	grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
	476	"xfs does not support inode format %d yet",
	477	diro->inode.format);
	478	}
	479	return 0;
	480	}
	481
	482
	483	static struct grub_xfs_data *
	484	grub_xfs_mount (grub_disk_t disk)
	485	{
	486	struct grub_xfs_data *data = 0;
487
488	data = grub_malloc (sizeof (struct grub_xfs_data));
489	if (!data)
490	return 0;
491
492	/* Read the superblock. */
493	if (grub_disk_read (disk, 0, 0,
494	sizeof (struct grub_xfs_sblock), (char *) &data->sblock))
495	goto fail;
496
497	if (grub_strncmp (data->sblock.magic, "XFSB", 4))
498	{
499	grub_error (GRUB_ERR_BAD_FS, "not a xfs filesystem");
500	goto fail;
501	}
502
503	data->diropen.data = data;
504	data->diropen.ino = data->sblock.rootino;
505	data->diropen.inode_read = 1;
688e5699	506	data->bsize = grub_be_to_cpu32 (data->sblock.bsize);
688e5699	507	data->agsize = grub_be_to_cpu32 (data->sblock.agsize);
b2499b29	508
	509	data->disk = disk;
	510	data->inode = &data->diropen.inode;
	511	data->pos = 0;
	512
	513	grub_xfs_read_inode (data, data->diropen.ino, data->inode);
	514
	515	return data;
	516	fail:
	517
	518	grub_free (data);
	519
	520	return 0;
	521	}
	522
	523	\f
	524	static grub_err_t
	525	grub_xfs_dir (grub_device_t device, const char *path,
	526	int (hook) (const char filename, int dir))
	527	{
	528	struct grub_xfs_data *data = 0;;
	529	struct grub_fshelp_node *fdiro = 0;
	530
	531	auto int NESTED_FUNC_ATTR iterate (const char *filename,
	532	enum grub_fshelp_filetype filetype,
	533	grub_fshelp_node_t node);
	534
	535	int NESTED_FUNC_ATTR iterate (const char *filename,
	536	enum grub_fshelp_filetype filetype,
	537	grub_fshelp_node_t node)
	538	{
	539	grub_free (node);
	540
	541	if (filetype == GRUB_FSHELP_DIR)
	542	return hook (filename, 1);
	543	else
	544	return hook (filename, 0);
	545
	546	return 0;
	547	}
	548
	549	#ifndef GRUB_UTIL
	550	grub_dl_ref (my_mod);
	551	#endif
	552
	553	data = grub_xfs_mount (device->disk);
	554	if (!data)
	555	goto fail;
	556
	557	grub_fshelp_find_file (path, &data->diropen, &fdiro, grub_xfs_iterate_dir,
	558	grub_xfs_read_symlink, GRUB_FSHELP_DIR);
	559	if (grub_errno)
	560	goto fail;
	561
	562	grub_xfs_iterate_dir (fdiro, iterate);
	563
	564	fail:
	565	if (fdiro != &data->diropen)
	566	grub_free (fdiro);
	567	grub_free (data);
	568
	569	#ifndef GRUB_UTIL
	570	grub_dl_unref (my_mod);
	571	#endif
572
573	return grub_errno;
574
575	return 0;
576	}
577
578
579	/* Open a file named NAME and initialize FILE. */
580	static grub_err_t
581	grub_xfs_open (struct grub_file file, const char name)
582	{
583	struct grub_xfs_data *data;
584	struct grub_fshelp_node *fdiro = 0;
585
586	#ifndef GRUB_UTIL
587	grub_dl_ref (my_mod);
588	#endif
589
590	data = grub_xfs_mount (file->device->disk);
591	if (!data)
592	goto fail;
593
594	grub_fshelp_find_file (name, &data->diropen, &fdiro, grub_xfs_iterate_dir,
595	grub_xfs_read_symlink, GRUB_FSHELP_REG);
596	if (grub_errno)
597	goto fail;
598
599	if (!fdiro->inode_read)
600	{
601	grub_xfs_read_inode (data, fdiro->ino, &fdiro->inode);
602	if (grub_errno)
603	goto fail;
604	}
605
606	grub_memcpy (data->inode,
607	&fdiro->inode,
608	sizeof (struct grub_xfs_inode));
609	grub_free (fdiro);
610
611	file->size = grub_be_to_cpu64 (data->inode->size);
612	file->data = data;
613	file->offset = 0;
614
615	return 0;
616
617	fail:
618	if (fdiro != &data->diropen)
619	grub_free (fdiro);
620	grub_free (data);
621
622	#ifndef GRUB_UTIL
623	grub_dl_unref (my_mod);
624	#endif
625
626	return grub_errno;
627	}
628
629
630	static grub_ssize_t
631	grub_xfs_read (grub_file_t file, char *buf, grub_ssize_t len)
632	{
633	struct grub_xfs_data *data =
634	(struct grub_xfs_data *) file->data;
635
636	return grub_xfs_read_file (&data->diropen, file->read_hook,
637	file->offset, len, buf);
638	}
639
640
641	static grub_err_t
642	grub_xfs_close (grub_file_t file)
643	{
644	grub_free (file->data);
645
646	#ifndef GRUB_UTIL
647	grub_dl_unref (my_mod);
648	#endif
649
650	return GRUB_ERR_NONE;
651	}
652
653
654	static grub_err_t
655	grub_xfs_label (grub_device_t device, char **label)
656	{
657	struct grub_xfs_data *data;
658	grub_disk_t disk = device->disk;
659
660	#ifndef GRUB_UTIL
661	grub_dl_ref (my_mod);
662	#endif
663
664	data = grub_xfs_mount (disk);
665	if (data)
666	*label = grub_strndup (data->sblock.label, 12);
667	else
668	*label = 0;
669
670	#ifndef GRUB_UTIL
671	grub_dl_unref (my_mod);
672	#endif
673
674	grub_free (data);
675
676	return grub_errno;
677	}
678
679	\f
680
681	static struct grub_fs grub_xfs_fs =
682	{
683	.name = "xfs",
684	.dir = grub_xfs_dir,
685	.open = grub_xfs_open,
686	.read = grub_xfs_read,
687	.close = grub_xfs_close,
688	.label = grub_xfs_label,
689	.next = 0
690	};
691
6d099807	692	GRUB_MOD_INIT(xfs)
b2499b29	693	{
b2499b29	694	grub_fs_register (&grub_xfs_fs);
6d099807	695	#ifndef GRUB_UTIL
b2499b29	696	my_mod = mod;
6d099807	697	#endif
b2499b29	698	}
b2499b29	699
6d099807	700	GRUB_MOD_FINI(xfs)
b2499b29	701	{
	702	grub_fs_unregister (&grub_xfs_fs);
	703	}
6d099807	704