В Mon, 14 Jul 2014 17:21:31 +0200
Jan Kara <j...@suse.cz> пишет:
> Add support for new XFS on disk format. We have to handle optional
> filetype fields in directory entries, additional CRC, LSN, UUID entries
> in some structures, etc.
>
> Signed-off-by: Jan Kara <j...@suse.cz>
> ---
> grub-core/fs/xfs.c | 249
> +++++++++++++++++++++++++++++++++++++----------------
> 1 file changed, 177 insertions(+), 72 deletions(-)
>
> diff --git a/grub-core/fs/xfs.c b/grub-core/fs/xfs.c
> index 7e247a32df5c..7f2582d33e02 100644
> --- a/grub-core/fs/xfs.c
> +++ b/grub-core/fs/xfs.c
> @@ -34,6 +34,15 @@ GRUB_MOD_LICENSE ("GPLv3+");
> #define XFS_INODE_FORMAT_EXT 2
> #define XFS_INODE_FORMAT_BTREE 3
>
> +/* Superblock version field flags */
> +#define XFS_SB_VERSION_NUMBITS 0x000f
> +#define XFS_SB_VERSION_MOREBITSBIT 0x8000
> +
> +/* features2 field flags */
> +#define XFS_SB_VERSION2_FTYPE 0x00000200 /* inode type in dir
> */
> +
> +/* incompat feature flags */
> +#define XFS_SB_FEAT_INCOMPAT_FTYPE (1 << 0) /* filetype in
> dirent */
>
> struct grub_xfs_sblock
> {
> @@ -45,7 +54,9 @@ struct grub_xfs_sblock
> grub_uint64_t rootino;
> grub_uint8_t unused3[20];
> grub_uint32_t agsize;
> - grub_uint8_t unused4[20];
> + grub_uint8_t unused4[12];
> + grub_uint16_t version;
> + grub_uint8_t unused5[6];
> grub_uint8_t label[12];
> grub_uint8_t log2_bsize;
> grub_uint8_t log2_sect;
> @@ -54,12 +65,19 @@ struct grub_xfs_sblock
> grub_uint8_t log2_agblk;
> grub_uint8_t unused6[67];
> grub_uint8_t log2_dirblk;
> + grub_uint8_t unused7[7];
> + grub_uint32_t features2;
> + grub_uint8_t unused8[4];
> + grub_uint32_t sb_features_compat;
> + grub_uint32_t sb_features_ro_compat;
> + grub_uint32_t sb_features_incompat;
> + grub_uint32_t sb_features_log_incompat;
> } GRUB_PACKED;
>
> struct grub_xfs_dir_header
> {
> grub_uint8_t count;
> - grub_uint8_t smallino;
> + grub_uint8_t largeino;
> union
> {
> grub_uint32_t i4;
> @@ -67,14 +85,16 @@ struct grub_xfs_dir_header
> } GRUB_PACKED parent;
> } GRUB_PACKED;
>
> +/* Structure for directory entry inlined in the inode */
> struct grub_xfs_dir_entry
> {
> grub_uint8_t len;
> grub_uint16_t offset;
> char name[1];
> - /* Inode number follows, 32 bits. */
> + /* Inode number follows, 32 / 64 bits. */
> } GRUB_PACKED;
>
> +/* Structure for directory entry in a block */
> struct grub_xfs_dir2_entry
> {
> grub_uint64_t inode;
> @@ -90,7 +110,8 @@ struct grub_xfs_btree_node
> grub_uint16_t numrecs;
> grub_uint64_t left;
> grub_uint64_t right;
> - grub_uint64_t keys[1];
> + /* In V5 here follow crc, uuid, etc. */
> + /* Then follow keys and block pointers */
> } GRUB_PACKED;
>
> struct grub_xfs_btree_root
> @@ -123,17 +144,6 @@ struct grub_xfs_inode
> grub_uint16_t unused3;
> grub_uint8_t fork_offset;
> grub_uint8_t unused4[17];
> - 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];
> - struct grub_xfs_btree_root btree;
> - } GRUB_PACKED data;
Can we make it grub_uint8_t xfs_v3_extra[76] or similar to avoid magic
numbers later when computing data offset?
> } GRUB_PACKED;
>
> struct grub_xfs_dirblock_tail
> @@ -157,6 +167,8 @@ struct grub_xfs_data
> int pos;
> int bsize;
> grub_uint32_t agsize;
> + unsigned int hasftype:1;
> + unsigned int hascrc:1;
> struct grub_fshelp_node diropen;
> };
>
> @@ -164,6 +176,24 @@ static grub_dl_t my_mod;
>
>
>
> +static int grub_xfs_sb_hascrc(struct grub_xfs_data *data)
> +{
> + return (grub_be_to_cpu16(data->sblock.version) & XFS_SB_VERSION_NUMBITS)
> == 5;
Could you define name for magic constant?
Also to avoid run-time computation:
data->sblock.version &
grub_cpu_to_b16_compile_time(XFS_SB_VERSION_NUMBITS) ==
grub_cpu_to_b16_compile_time(5)
> +}
> +
> +static int grub_xfs_sb_hasftype(struct grub_xfs_data *data)
> +{
> + grub_uint32_t version = grub_be_to_cpu16(data->sblock.version);
> +
> + if ((version & XFS_SB_VERSION_NUMBITS) == 5 &&
> + grub_be_to_cpu32(data->sblock.sb_features_incompat) &
> XFS_SB_FEAT_INCOMPAT_FTYPE)
> + return 1;
> + if (version & XFS_SB_VERSION_MOREBITSBIT &&
> + grub_be_to_cpu32(data->sblock.features2) & XFS_SB_VERSION2_FTYPE)
> + return 1;
> + return 0;
> +}
> +
Same. All are constants, so *_compile_time.
> /* Filetype information as used in inodes. */
> #define FILETYPE_INO_MASK 0170000
> #define FILETYPE_INO_REG 0100000
> @@ -219,18 +249,6 @@ GRUB_XFS_EXTENT_SIZE (grub_xfs_extent *exts, int ex)
> return (grub_be_to_cpu32 (exts[ex][3]) & ((1 << 21) - 1));
> }
>
> -static inline int
> -GRUB_XFS_ROUND_TO_DIRENT (int pos)
> -{
> - return ((((pos) + 8 - 1) / 8) * 8);
> -}
> -
> -static inline int
> -GRUB_XFS_NEXT_DIRENT (int pos, int len)
> -{
> - return (pos) + GRUB_XFS_ROUND_TO_DIRENT (8 + 1 + len + 2);
> -}
> -
>
> static inline grub_uint64_t
> grub_xfs_inode_block (struct grub_xfs_data *data,
> @@ -261,6 +279,96 @@ grub_xfs_inode_size(struct grub_xfs_data *data)
> return 1 << data->sblock.log2_inode;
> }
>
> +static void *
> +grub_xfs_inode_data(struct grub_xfs_inode *inode)
> +{
> + if (inode->version <= 2)
> + return ((char *)inode) + 100;
That is sizeof(struct grub_xfs_inode) in your patch, right?
> + return ((char *)inode) + 176;
Please avoid magic numbers. At least give it meaningful name, or as
suggested above just define structure to contain it.
> +}
> +
> +static struct grub_xfs_dir_entry *
> +grub_xfs_inline_de(struct grub_xfs_dir_header *head)
> +{
> + /*
> + * With small inode numbers the header is 4 bytes smaller because of
> + * smaller parent pointer
> + */
> + return (void *)(((char *)head) + sizeof(struct grub_xfs_dir_header) -
> + (head->largeino ? 0 : sizeof(grub_uint32_t)));
> +}
> +
> +static grub_uint8_t *
> +grub_xfs_inline_de_inopos(struct grub_xfs_data *data,
> + struct grub_xfs_dir_entry *de)
> +{
> + return ((grub_uint8_t *)(de + 1)) + de->len - 1 +
The outer parens are somehow confusing.
> + (data->hasftype ? 1 : 0);
> +}
> +
> +static struct grub_xfs_dir_entry *
> +grub_xfs_inline_next_de(struct grub_xfs_data *data,
> + struct grub_xfs_dir_header *head,
> + struct grub_xfs_dir_entry *de)
> +{
> + char *p = (char *)de + sizeof(struct grub_xfs_dir_entry) - 1 + de->len;
> +
> + p += head->largeino ? sizeof(grub_uint64_t) : sizeof(grub_uint32_t);
> + if (data->hasftype)
> + p++;
> +
> + return (struct grub_xfs_dir_entry *)p;
> +}
> +
> +static struct grub_xfs_dirblock_tail *
> +grub_xfs_dir_tail(struct grub_xfs_data *data, void *dirblock)
> +{
> + int dirblksize = 1 << (data->sblock.log2_bsize + data->sblock.log2_dirblk);
> +
> + return (struct grub_xfs_dirblock_tail *)
> + ((char *)dirblock + dirblksize - sizeof (struct grub_xfs_dirblock_tail));
> +}
> +
> +static struct grub_xfs_dir2_entry *
> +grub_xfs_first_de(struct grub_xfs_data *data, void *dirblock)
> +{
> + if (data->hascrc)
> + return (struct grub_xfs_dir2_entry *)((char *)dirblock + 64);
> + return (struct grub_xfs_dir2_entry *)((char *)dirblock + 16);
> +}
> +
> +static inline int
> +grub_xfs_round_dirent_size (int len)
> +{
> + return (len + 7) & ~7;
> +}
ALIGN_UP?
> +
> +static struct grub_xfs_dir2_entry *
> +grub_xfs_next_de(struct grub_xfs_data *data, struct grub_xfs_dir2_entry *de)
> +{
> + int size = sizeof (struct grub_xfs_dir2_entry) + de->len + 2 /* Tag */;
> +
> + if (data->hasftype)
> + size++; /* File type */
> + return (struct grub_xfs_dir2_entry *)
> + (((char *)de) + grub_xfs_round_dirent_size (size));
What's wrong with ALIGN_UP (size, 8)?
> +}
> +
> +static grub_uint64_t *
> +grub_xfs_btree_keys(struct grub_xfs_data *data,
> + struct grub_xfs_btree_node *leaf)
> +{
> + char *p = (char *)(leaf + 1);
> +
> + if (data->hascrc)
> + p += 48; /* crc, uuid, ... */
> + /*
> + * We have to first type to void * to avoid complaints about possible
> + * alignment issues on some architectures
> + */
> + return (grub_uint64_t *)(void *)p;
Leaving it as grub_uint64_t keys and using &keys[6] would avoid this
warning as well, not? Also having keys[0] will likely simplify other
places as well (we do require GCC in any case).
> +}
> +
> static grub_err_t
> grub_xfs_read_inode (struct grub_xfs_data *data, grub_uint64_t ino,
> struct grub_xfs_inode *inode)
> @@ -268,6 +376,9 @@ grub_xfs_read_inode (struct grub_xfs_data *data,
> grub_uint64_t ino,
> grub_uint64_t block = grub_xfs_inode_block (data, ino);
> int offset = grub_xfs_inode_offset (data, ino);
>
> + grub_dprintf("xfs", "Reading inode (%llu) - %llu, %d\n",
> + (unsigned long long) ino,
> + (unsigned long long) block, offset);
> /* Read the inode. */
> if (grub_disk_read (data->disk, block, offset, grub_xfs_inode_size(data),
> inode))
> @@ -290,6 +401,7 @@ grub_xfs_read_block (grub_fshelp_node_t node,
> grub_disk_addr_t fileblock)
>
> if (node->inode.format == XFS_INODE_FORMAT_BTREE)
> {
> + struct grub_xfs_btree_root *root;
> const grub_uint64_t *keys;
> int recoffset;
>
> @@ -297,15 +409,15 @@ grub_xfs_read_block (grub_fshelp_node_t node,
> grub_disk_addr_t fileblock)
> if (leaf == 0)
> return 0;
>
> - nrec = grub_be_to_cpu16 (node->inode.data.btree.numrecs);
> - keys = &node->inode.data.btree.keys[0];
> + root = grub_xfs_inode_data(&node->inode);
> + nrec = grub_be_to_cpu16 (root->numrecs);
> + keys = &root->keys[0];
> if (node->inode.fork_offset)
> recoffset = (node->inode.fork_offset - 1) / 2;
> else
> recoffset = (grub_xfs_inode_size(node->data)
> - - ((char *) &node->inode.data.btree.keys
> - - (char *) &node->inode))
> - / (2 * sizeof (grub_uint64_t));
> + - ((char *) keys - (char *) &node->inode))
> + / (2 * sizeof (grub_uint64_t));
> do
> {
> int i;
> @@ -327,7 +439,10 @@ grub_xfs_read_block (grub_fshelp_node_t node,
> grub_disk_addr_t fileblock)
> 0, node->data->bsize, leaf))
> return 0;
>
> - if (grub_strncmp ((char *) leaf->magic, "BMAP", 4))
> + if ((!node->data->hascrc &&
> + grub_strncmp ((char *) leaf->magic, "BMAP", 4)) ||
> + (node->data->hascrc &&
> + grub_strncmp ((char *) leaf->magic, "BMA3", 4)))
> {
> grub_free (leaf);
> grub_error (GRUB_ERR_BAD_FS, "not a correct XFS BMAP node");
> @@ -335,8 +450,8 @@ grub_xfs_read_block (grub_fshelp_node_t node,
> grub_disk_addr_t fileblock)
> }
>
> nrec = grub_be_to_cpu16 (leaf->numrecs);
> - keys = &leaf->keys[0];
> - recoffset = ((node->data->bsize - ((char *) &leaf->keys
> + keys = grub_xfs_btree_keys(node->data, leaf);
> + recoffset = ((node->data->bsize - ((char *) keys
> - (char *) leaf))
> / (2 * sizeof (grub_uint64_t)));
> }
> @@ -346,7 +461,7 @@ grub_xfs_read_block (grub_fshelp_node_t node,
> grub_disk_addr_t fileblock)
> else if (node->inode.format == XFS_INODE_FORMAT_EXT)
> {
> nrec = grub_be_to_cpu32 (node->inode.nextents);
> - exts = &node->inode.data.extents[0];
> + exts = grub_xfs_inode_data(&node->inode);
> }
> else
> {
> @@ -404,7 +519,7 @@ grub_xfs_read_symlink (grub_fshelp_node_t node)
> switch (node->inode.format)
> {
> case XFS_INODE_FORMAT_INO:
> - return grub_strndup (node->inode.data.raw, size);
> + return grub_strndup (grub_xfs_inode_data(&node->inode), size);
>
> case XFS_INODE_FORMAT_EXT:
> {
> @@ -501,23 +616,18 @@ grub_xfs_iterate_dir (grub_fshelp_node_t dir,
> {
> 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;
> + struct grub_xfs_dir_header *head = grub_xfs_inode_data(&diro->inode);
> + struct grub_xfs_dir_entry *de = grub_xfs_inline_de(head);
> + int smallino = !head->largeino;
> 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.i4);
> - /* The header is a bit smaller than usual. */
> - de = (struct grub_xfs_dir_entry *) ((char *) de - 4);
> - }
> + parent = grub_be_to_cpu32 (head->parent.i4);
> else
> - {
> - parent = grub_be_to_cpu64(diro->inode.data.dir.dirhead.parent.i8);
> - }
> + parent = grub_be_to_cpu64 (head->parent.i8);
>
> /* Synthesize the direntries for `.' and `..'. */
> if (iterate_dir_call_hook (diro->ino, ".", &ctx))
> @@ -526,12 +636,10 @@ grub_xfs_iterate_dir (grub_fshelp_node_t dir,
> if (iterate_dir_call_hook (parent, "..", &ctx))
> return 1;
>
> - for (i = 0; i < diro->inode.data.dir.dirhead.count; i++)
> + for (i = 0; i < head->count; i++)
> {
> grub_uint64_t ino;
> - grub_uint8_t *inopos = (((grub_uint8_t *) de)
> - + sizeof (struct grub_xfs_dir_entry)
> - + de->len - 1);
> + grub_uint8_t *inopos = grub_xfs_inline_de_inopos(dir->data, de);
> grub_uint8_t c;
>
> /* inopos might be unaligned. */
> @@ -556,10 +664,7 @@ grub_xfs_iterate_dir (grub_fshelp_node_t dir,
> return 1;
> de->name[de->len] = c;
>
> - 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));
> + de = grub_xfs_inline_next_de(dir->data, head, de);
> }
> break;
> }
> @@ -586,15 +691,11 @@ grub_xfs_iterate_dir (grub_fshelp_node_t dir,
> >> dirblk_log2);
> blk++)
> {
> - /* The header is skipped, the first direntry is stored
> - from byte 16. */
> - int pos = 16;
> + struct grub_xfs_dir2_entry *direntry =
> + grub_xfs_first_de(dir->data, dirblock);
> int entries;
> - int tail_start = (dirblk_size
> - - sizeof (struct grub_xfs_dirblock_tail));
> -
> - struct grub_xfs_dirblock_tail *tail;
> - tail = (struct grub_xfs_dirblock_tail *) &dirblock[tail_start];
> + struct grub_xfs_dirblock_tail *tail =
> + grub_xfs_dir_tail(dir->data, dirblock);
>
> numread = grub_xfs_read_file (dir, 0, 0,
> blk << dirblk_log2,
> @@ -606,13 +707,11 @@ grub_xfs_iterate_dir (grub_fshelp_node_t dir,
> - grub_be_to_cpu32 (tail->leaf_stale));
>
> /* Iterate over all entries within this block. */
> - while (pos < tail_start)
> + while ((char *)direntry < (char *)tail)
> {
> - struct grub_xfs_dir2_entry *direntry;
> grub_uint8_t *freetag;
> char *filename;
>
> - direntry = (struct grub_xfs_dir2_entry *) &dirblock[pos];
> freetag = (grub_uint8_t *) direntry;
>
> if (grub_get_unaligned16 (freetag) == 0XFFFF)
> @@ -620,14 +719,16 @@ grub_xfs_iterate_dir (grub_fshelp_node_t dir,
> grub_uint8_t *skip = (freetag + sizeof (grub_uint16_t));
>
> /* This entry is not used, go to the next one. */
> - pos += grub_be_to_cpu16 (grub_get_unaligned16 (skip));
> + direntry = (struct grub_xfs_dir2_entry *)
> + (((char *)direntry) +
> + grub_be_to_cpu16 (grub_get_unaligned16 (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 = (char *)(direntry + 1);
> + /* The byte after the filename is for the filetype, padding, or
> + tag, which is not used by GRUB. So it can be overwritten. */
> filename[direntry->len] = '\0';
>
> if (iterate_dir_call_hook (grub_be_to_cpu64(direntry->inode),
> @@ -644,8 +745,7 @@ grub_xfs_iterate_dir (grub_fshelp_node_t dir,
> break;
>
> /* Select the next directory entry. */
> - pos = GRUB_XFS_NEXT_DIRENT (pos, direntry->len);
> - pos = GRUB_XFS_ROUND_TO_DIRENT (pos);
> + direntry = grub_xfs_next_de(dir->data, direntry);
> }
> }
> grub_free (dirblock);
> @@ -670,6 +770,7 @@ grub_xfs_mount (grub_disk_t disk)
> if (!data)
> return 0;
>
> + grub_dprintf("xfs", "Reading sb\n");
> /* Read the superblock. */
> if (grub_disk_read (disk, 0, 0,
> sizeof (struct grub_xfs_sblock), &data->sblock))
> @@ -697,9 +798,13 @@ grub_xfs_mount (grub_disk_t disk)
> data->diropen.inode_read = 1;
> data->bsize = grub_be_to_cpu32 (data->sblock.bsize);
> data->agsize = grub_be_to_cpu32 (data->sblock.agsize);
> + data->hasftype = grub_xfs_sb_hasftype(data);
> + data->hascrc = grub_xfs_sb_hascrc(data);
>
> data->disk = disk;
> data->pos = 0;
> + grub_dprintf("xfs", "Reading root ino %llu\n",
> + (unsigned long long) grub_cpu_to_be64(data->sblock.rootino));
>
> grub_xfs_read_inode (data, data->diropen.ino, &data->diropen.inode);
>
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