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Author SHA1 Message Date
Andrei Borzenkov
e897f83635 Merge branch 'master' into andrey/ext4_inline_data
Conflicts:
	grub-core/fs/ext2.c
2016-07-11 07:23:13 +03:00
Andrey Borzenkov
d4af83fc60 ext4 inline data support 2013-12-18 19:53:19 +01:00

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@@ -89,6 +89,9 @@ GRUB_MOD_LICENSE ("GPLv3+");
#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
#define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100
#define EXT4_FEATURE_RO_COMPAT_BIGALLOC 0x0200
#define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM 0x0400
/* Superblock filesystem feature flags (back-incompatible)
* A filesystem with any of these enabled should not be attempted to be read
* by a driver that does not understand them, since they usually indicate
@@ -102,6 +105,11 @@ GRUB_MOD_LICENSE ("GPLv3+");
#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
#define EXT4_FEATURE_INCOMPAT_MMP 0x0100
#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
#define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 /* EA in inode */
#define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 /* data in dirent */
#define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM 0x2000 /* use crc32c for bg */
#define EXT4_FEATURE_INCOMPAT_LARGEDIR 0x4000 /* >2GB or 3-lvl htree */
#define EXT4_FEATURE_INCOMPAT_INLINE_DATA 0x8000 /* data in inode */
/* The set of back-incompatible features this driver DOES support. Add (OR)
* flags here as the related features are implemented into the driver. */
@@ -109,7 +117,8 @@ GRUB_MOD_LICENSE ("GPLv3+");
| EXT4_FEATURE_INCOMPAT_EXTENTS \
| EXT4_FEATURE_INCOMPAT_FLEX_BG \
| EXT2_FEATURE_INCOMPAT_META_BG \
| EXT4_FEATURE_INCOMPAT_64BIT)
| EXT4_FEATURE_INCOMPAT_64BIT \
| EXT4_FEATURE_INCOMPAT_INLINE_DATA)
/* List of rationales for the ignored "incompatible" features:
* needs_recovery: Not really back-incompatible - was added as such to forbid
* ext2 drivers from mounting an ext3 volume with a dirty
@@ -316,12 +325,40 @@ struct grub_ext4_extent_idx
grub_uint16_t unused;
};
#define EXT4_XATTR_MAGIC 0xEA020000
#define EXT4_XATTR_INDEX_SYSTEM 7
#define EXT4_XATTR_SYSTEM_DATA "data"
#define EXT4_INLINE_DOTDOT_SIZE 4
struct grub_ext4_xattr_entry
{
grub_uint8_t name_len; /* length of name */
grub_uint8_t name_index; /* attribute name index */
grub_uint16_t value_offs; /* offset in disk block of value */
grub_uint32_t value_block; /* disk block attribute is stored on */
grub_uint32_t value_size; /* size of attribute value */
grub_uint32_t hash; /* hash value of name and value */
char name[0]; /* attribute name */
} GRUB_PACKED;
#define EXT4_XATTR_LEN(name_len) \
(ALIGN_UP((name_len) + sizeof(struct grub_ext4_xattr_entry), 4))
#define EXT4_XATTR_NEXT(entry) \
((struct grub_ext4_xattr_entry *)( \
(char *)(entry) + EXT4_XATTR_LEN((entry)->name_len)))
#define IS_LAST_ENTRY(entry) (grub_get_unaligned32 (entry) == 0)
struct grub_fshelp_node
{
struct grub_ext2_data *data;
struct grub_ext2_inode inode;
int ino;
grub_uint32_t ino;
int inode_read;
grub_disk_addr_t inode_base; /* Inode filesystem block */
grub_off_t inode_offs; /* Inode offset in filesystem block */
grub_off_t inline_offs; /* Offset of inline data from start of inode */
grub_size_t inline_size; /* Size of inline data */
};
/* Information about a "mounted" ext2 filesystem. */
@@ -367,6 +404,66 @@ group_has_super_block (struct grub_ext2_data *data, grub_uint64_t group)
is_power_of(group, 3));
}
/* Inline data is stored using inline extended attributes. Attributes consist
of entry and value. Entries start after inode proper, following 4 bytes
magic header. Each entry is 4 bytes aligned, end of list is marked with
4 bytes zero. Values are stored after entries.
Inline data is stored as system attribute with name "data". First part of
data is kept in space reserved for block pointers, so it is valid for value
size to be zero. Offset is apparently non-zero even in this case.
*/
inline static void
grub_ext2_find_inline_data (struct grub_fshelp_node *node, grub_size_t isize,
struct grub_ext2_inode *inode)
{
grub_size_t extra;
grub_uint8_t *ihdr;
struct grub_ext4_xattr_entry *entry;
grub_uint8_t *iend = (grub_uint8_t *) inode + isize - sizeof (grub_uint32_t);
node->inline_offs = 0;
if (isize < EXT2_GOOD_OLD_INODE_SIZE + sizeof (grub_uint16_t))
return;
extra = grub_le_to_cpu16 (*((grub_uint16_t *) inode
+ (EXT2_GOOD_OLD_INODE_SIZE / 2)));
if (EXT2_GOOD_OLD_INODE_SIZE + extra + 4 > isize)
return;
ihdr = ((grub_uint8_t *) inode
+ EXT2_GOOD_OLD_INODE_SIZE + extra);
if (grub_get_unaligned32 (ihdr)
!= grub_cpu_to_le32_compile_time (EXT4_XATTR_MAGIC))
return;
entry = (struct grub_ext4_xattr_entry *) (ihdr + 4);
for (; (grub_uint8_t *) entry < iend && !IS_LAST_ENTRY(entry);
entry = EXT4_XATTR_NEXT(entry))
{
grub_size_t value_size;
grub_off_t value_offs;
if (entry->value_block)
continue;
if (entry->name_index != EXT4_XATTR_INDEX_SYSTEM)
continue;
if (entry->name_len != sizeof (EXT4_XATTR_SYSTEM_DATA) - 1)
continue;
if (grub_memcmp (entry->name, EXT4_XATTR_SYSTEM_DATA, sizeof (EXT4_XATTR_SYSTEM_DATA) - 1))
continue;
value_size = grub_le_to_cpu32 (entry->value_size);
value_offs = grub_le_to_cpu16 (entry->value_offs);
/* extra is additional size of base inode. Extended attributes start
after base inode, offset is calculated from the end of extended
attributes header.
*/
if (EXT2_GOOD_OLD_INODE_SIZE + extra + 4 + value_offs + value_size > isize)
continue;
node->inline_offs = EXT2_GOOD_OLD_INODE_SIZE + extra + 4 + value_offs;
node->inline_size = value_size;
return;
}
}
/* Read into BLKGRP the blockgroup descriptor of blockgroup GROUP of
the mounted filesystem DATA. */
inline static grub_err_t
@@ -568,6 +665,52 @@ grub_ext2_read_file (grub_fshelp_node_t node,
grub_disk_read_hook_t read_hook, void *read_hook_data,
grub_off_t pos, grub_size_t len, char *buf)
{
/* Does inode have inine data? */
if (node->inline_offs)
{
grub_size_t cp_len;
grub_off_t cp_pos;
grub_ssize_t total = 0;
if (pos < 60)
{
cp_pos = node->inode_offs + ((char *)&node->inode.blocks - (char *)&node->inode) + pos;
cp_len = 60 - pos;
if (cp_len > len)
cp_len = len;
node->data->disk->read_hook = read_hook;
node->data->disk->read_hook_data = read_hook_data;
grub_disk_read (node->data->disk, node->inode_base, cp_pos,
cp_len, buf);
node->data->disk->read_hook = 0;
if (grub_errno)
return -1;
pos += cp_len;
buf += cp_len;
len -= cp_len;
total = cp_len;
}
if (len)
{
pos -= 60;
if (pos >= node->inline_size)
return 0;
if (pos + len > node->inline_size)
len = node->inline_size - pos;
cp_pos = node->inode_offs + node->inline_offs + pos;
node->data->disk->read_hook = read_hook;
node->data->disk->read_hook_data = read_hook_data;
grub_disk_read (node->data->disk, node->inode_base, cp_pos,
len, buf);
node->data->disk->read_hook = 0;
if (!grub_errno)
total += len;
}
return total;
}
return grub_fshelp_read_file (node->data->disk, node,
read_hook, read_hook_data,
pos, len, buf, grub_ext2_read_block,
@@ -578,17 +721,28 @@ grub_ext2_read_file (grub_fshelp_node_t node,
}
/* Read the inode INO for the file described by DATA into INODE. */
/* Read the inode NODE->INO for the file described by NODE->DATA into NODE->INODE. */
static grub_err_t
grub_ext2_read_inode (struct grub_ext2_data *data,
int ino, struct grub_ext2_inode *inode)
grub_ext2_read_inode (struct grub_fshelp_node *node)
{
struct grub_ext2_data *data = node->data;
grub_uint32_t ino = node->ino;
struct grub_ext2_block_group blkgrp;
struct grub_ext2_sblock *sblock = &data->sblock;
int inodes_per_block;
unsigned int blkno;
unsigned int blkoff;
grub_disk_addr_t base;
struct grub_ext2_inode *full_inode;
grub_size_t full_isize;
if (node->inode_read)
return 0;
full_isize = EXT2_INODE_SIZE (data);
full_inode = grub_malloc (full_isize);
if (!full_inode)
return 0;
/* It is easier to calculate if the first inode is 0. */
ino--;
@@ -597,9 +751,12 @@ grub_ext2_read_inode (struct grub_ext2_data *data,
ino / grub_le_to_cpu32 (sblock->inodes_per_group),
&blkgrp);
if (grub_errno)
return grub_errno;
{
grub_free (full_inode);
return grub_errno;
}
inodes_per_block = EXT2_BLOCK_SIZE (data) / EXT2_INODE_SIZE (data);
inodes_per_block = EXT2_BLOCK_SIZE (data) / full_isize;
blkno = (ino % grub_le_to_cpu32 (sblock->inodes_per_group))
/ inodes_per_block;
blkoff = (ino % grub_le_to_cpu32 (sblock->inodes_per_group))
@@ -611,12 +768,19 @@ grub_ext2_read_inode (struct grub_ext2_data *data,
<< 32);
/* Read the inode. */
if (grub_disk_read (data->disk,
((base + blkno) << LOG2_EXT2_BLOCK_SIZE (data)),
EXT2_INODE_SIZE (data) * blkoff,
sizeof (struct grub_ext2_inode), inode))
return grub_errno;
node->inode_base = (base + blkno) << LOG2_EXT2_BLOCK_SIZE (data);
node->inode_offs = full_isize * blkoff;
if (grub_disk_read (data->disk, node->inode_base, node->inode_offs,
full_isize, full_inode))
{
grub_free (full_inode);
return grub_errno;
}
grub_memcpy (&node->inode, full_inode, sizeof (struct grub_ext2_inode));
node->inode_read = 1;
grub_ext2_find_inline_data (node, full_isize, full_inode);
grub_free (full_inode);
return 0;
}
@@ -677,11 +841,9 @@ grub_ext2_mount (grub_disk_t disk)
data->diropen.data = data;
data->diropen.ino = 2;
data->diropen.inode_read = 1;
data->inode = &data->diropen.inode;
grub_ext2_read_inode (data, 2, data->inode);
grub_ext2_read_inode (&data->diropen);
if (grub_errno)
goto fail;
@@ -701,12 +863,9 @@ grub_ext2_read_symlink (grub_fshelp_node_t node)
char *symlink;
struct grub_fshelp_node *diro = node;
if (! diro->inode_read)
{
grub_ext2_read_inode (diro->data, diro->ino, &diro->inode);
if (grub_errno)
return 0;
}
grub_ext2_read_inode (diro);
if (grub_errno)
return 0;
symlink = grub_malloc (grub_le_to_cpu32 (diro->inode.size) + 1);
if (! symlink)
@@ -742,11 +901,42 @@ grub_ext2_iterate_dir (grub_fshelp_node_t dir,
unsigned int fpos = 0;
struct grub_fshelp_node *diro = (struct grub_fshelp_node *) dir;
if (! diro->inode_read)
grub_ext2_read_inode (diro);
if (grub_errno)
return 0;
/* Inline directory has only parent inode number and no explicit entries
for . or ..; simulate them */
if (diro->inline_offs)
{
grub_ext2_read_inode (diro->data, diro->ino, &diro->inode);
struct grub_fshelp_node *dot, *dotdot;
grub_uint32_t inum;
dot = grub_malloc (sizeof (struct grub_fshelp_node));
if (!dot)
return 0;
dot->inode_read = 0;
dot->ino = dir->ino;
dot->data = diro->data;
if (hook (".", FILETYPE_DIRECTORY, dot, hook_data))
return 1;
/* First 4 bytes of inline directory data is parent inode number */
grub_ext2_read_file (diro, 0, 0, 0, EXT4_INLINE_DOTDOT_SIZE, (char *) &inum);
if (grub_errno)
return 0;
dotdot = grub_malloc (sizeof (struct grub_fshelp_node));
if (!dotdot)
return 0;
dotdot->inode_read = 0;
dotdot->ino = grub_le_to_cpu32 (inum);
dotdot->data = diro->data;
if (hook ("..", FILETYPE_DIRECTORY, dotdot, hook_data))
return 1;
fpos = EXT4_INLINE_DOTDOT_SIZE;
}
/* Search the file. */
@@ -797,17 +987,13 @@ grub_ext2_iterate_dir (grub_fshelp_node_t dir,
{
/* The filetype can not be read from the dirent, read
the inode to get more information. */
grub_ext2_read_inode (diro->data,
grub_le_to_cpu32 (dirent.inode),
&fdiro->inode);
grub_ext2_read_inode (fdiro);
if (grub_errno)
{
grub_free (fdiro);
return 0;
}
fdiro->inode_read = 1;
if ((grub_le_to_cpu16 (fdiro->inode.mode)
& FILETYPE_INO_MASK) == FILETYPE_INO_DIRECTORY)
type = GRUB_FSHELP_DIR;
@@ -852,14 +1038,11 @@ grub_ext2_open (struct grub_file *file, const char *name)
if (err)
goto fail;
if (! fdiro->inode_read)
{
err = grub_ext2_read_inode (data, fdiro->ino, &fdiro->inode);
if (err)
goto fail;
}
err = grub_ext2_read_inode (fdiro);
if (err)
goto fail;
grub_memcpy (data->inode, &fdiro->inode, sizeof (struct grub_ext2_inode));
grub_memcpy (&data->diropen, fdiro, sizeof (struct grub_fshelp_node));
grub_free (fdiro);
file->size = grub_le_to_cpu32 (data->inode->size);
@@ -918,13 +1101,9 @@ grub_ext2_dir_iter (const char *filename, enum grub_fshelp_filetype filetype,
struct grub_dirhook_info info;
grub_memset (&info, 0, sizeof (info));
if (! node->inode_read)
{
grub_ext2_read_inode (ctx->data, node->ino, &node->inode);
if (!grub_errno)
node->inode_read = 1;
grub_errno = GRUB_ERR_NONE;
}
grub_ext2_read_inode (node);
grub_errno = GRUB_ERR_NONE;
if (node->inode_read)
{
info.mtimeset = 1;