v4.19.13 snapshot.
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
new file mode 100644
index 0000000..ffa2575
--- /dev/null
+++ b/fs/ext4/namei.c
@@ -0,0 +1,3863 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/ext4/namei.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/namei.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ * Directory entry file type support and forward compatibility hooks
+ * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
+ * Hash Tree Directory indexing (c)
+ * Daniel Phillips, 2001
+ * Hash Tree Directory indexing porting
+ * Christopher Li, 2002
+ * Hash Tree Directory indexing cleanup
+ * Theodore Ts'o, 2002
+ */
+
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <linux/time.h>
+#include <linux/fcntl.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/quotaops.h>
+#include <linux/buffer_head.h>
+#include <linux/bio.h>
+#include <linux/iversion.h>
+#include "ext4.h"
+#include "ext4_jbd2.h"
+
+#include "xattr.h"
+#include "acl.h"
+
+#include <trace/events/ext4.h>
+/*
+ * define how far ahead to read directories while searching them.
+ */
+#define NAMEI_RA_CHUNKS 2
+#define NAMEI_RA_BLOCKS 4
+#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
+
+static struct buffer_head *ext4_append(handle_t *handle,
+ struct inode *inode,
+ ext4_lblk_t *block)
+{
+ struct buffer_head *bh;
+ int err;
+
+ if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb &&
+ ((inode->i_size >> 10) >=
+ EXT4_SB(inode->i_sb)->s_max_dir_size_kb)))
+ return ERR_PTR(-ENOSPC);
+
+ *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
+
+ bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE);
+ if (IS_ERR(bh))
+ return bh;
+ inode->i_size += inode->i_sb->s_blocksize;
+ EXT4_I(inode)->i_disksize = inode->i_size;
+ BUFFER_TRACE(bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, bh);
+ if (err) {
+ brelse(bh);
+ ext4_std_error(inode->i_sb, err);
+ return ERR_PTR(err);
+ }
+ return bh;
+}
+
+static int ext4_dx_csum_verify(struct inode *inode,
+ struct ext4_dir_entry *dirent);
+
+typedef enum {
+ EITHER, INDEX, DIRENT
+} dirblock_type_t;
+
+#define ext4_read_dirblock(inode, block, type) \
+ __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__)
+
+static struct buffer_head *__ext4_read_dirblock(struct inode *inode,
+ ext4_lblk_t block,
+ dirblock_type_t type,
+ const char *func,
+ unsigned int line)
+{
+ struct buffer_head *bh;
+ struct ext4_dir_entry *dirent;
+ int is_dx_block = 0;
+
+ bh = ext4_bread(NULL, inode, block, 0);
+ if (IS_ERR(bh)) {
+ __ext4_warning(inode->i_sb, func, line,
+ "inode #%lu: lblock %lu: comm %s: "
+ "error %ld reading directory block",
+ inode->i_ino, (unsigned long)block,
+ current->comm, PTR_ERR(bh));
+
+ return bh;
+ }
+ if (!bh) {
+ ext4_error_inode(inode, func, line, block,
+ "Directory hole found");
+ return ERR_PTR(-EFSCORRUPTED);
+ }
+ dirent = (struct ext4_dir_entry *) bh->b_data;
+ /* Determine whether or not we have an index block */
+ if (is_dx(inode)) {
+ if (block == 0)
+ is_dx_block = 1;
+ else if (ext4_rec_len_from_disk(dirent->rec_len,
+ inode->i_sb->s_blocksize) ==
+ inode->i_sb->s_blocksize)
+ is_dx_block = 1;
+ }
+ if (!is_dx_block && type == INDEX) {
+ ext4_error_inode(inode, func, line, block,
+ "directory leaf block found instead of index block");
+ brelse(bh);
+ return ERR_PTR(-EFSCORRUPTED);
+ }
+ if (!ext4_has_metadata_csum(inode->i_sb) ||
+ buffer_verified(bh))
+ return bh;
+
+ /*
+ * An empty leaf block can get mistaken for a index block; for
+ * this reason, we can only check the index checksum when the
+ * caller is sure it should be an index block.
+ */
+ if (is_dx_block && type == INDEX) {
+ if (ext4_dx_csum_verify(inode, dirent))
+ set_buffer_verified(bh);
+ else {
+ ext4_error_inode(inode, func, line, block,
+ "Directory index failed checksum");
+ brelse(bh);
+ return ERR_PTR(-EFSBADCRC);
+ }
+ }
+ if (!is_dx_block) {
+ if (ext4_dirent_csum_verify(inode, dirent))
+ set_buffer_verified(bh);
+ else {
+ ext4_error_inode(inode, func, line, block,
+ "Directory block failed checksum");
+ brelse(bh);
+ return ERR_PTR(-EFSBADCRC);
+ }
+ }
+ return bh;
+}
+
+#ifndef assert
+#define assert(test) J_ASSERT(test)
+#endif
+
+#ifdef DX_DEBUG
+#define dxtrace(command) command
+#else
+#define dxtrace(command)
+#endif
+
+struct fake_dirent
+{
+ __le32 inode;
+ __le16 rec_len;
+ u8 name_len;
+ u8 file_type;
+};
+
+struct dx_countlimit
+{
+ __le16 limit;
+ __le16 count;
+};
+
+struct dx_entry
+{
+ __le32 hash;
+ __le32 block;
+};
+
+/*
+ * dx_root_info is laid out so that if it should somehow get overlaid by a
+ * dirent the two low bits of the hash version will be zero. Therefore, the
+ * hash version mod 4 should never be 0. Sincerely, the paranoia department.
+ */
+
+struct dx_root
+{
+ struct fake_dirent dot;
+ char dot_name[4];
+ struct fake_dirent dotdot;
+ char dotdot_name[4];
+ struct dx_root_info
+ {
+ __le32 reserved_zero;
+ u8 hash_version;
+ u8 info_length; /* 8 */
+ u8 indirect_levels;
+ u8 unused_flags;
+ }
+ info;
+ struct dx_entry entries[0];
+};
+
+struct dx_node
+{
+ struct fake_dirent fake;
+ struct dx_entry entries[0];
+};
+
+
+struct dx_frame
+{
+ struct buffer_head *bh;
+ struct dx_entry *entries;
+ struct dx_entry *at;
+};
+
+struct dx_map_entry
+{
+ u32 hash;
+ u16 offs;
+ u16 size;
+};
+
+/*
+ * This goes at the end of each htree block.
+ */
+struct dx_tail {
+ u32 dt_reserved;
+ __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */
+};
+
+static inline ext4_lblk_t dx_get_block(struct dx_entry *entry);
+static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value);
+static inline unsigned dx_get_hash(struct dx_entry *entry);
+static void dx_set_hash(struct dx_entry *entry, unsigned value);
+static unsigned dx_get_count(struct dx_entry *entries);
+static unsigned dx_get_limit(struct dx_entry *entries);
+static void dx_set_count(struct dx_entry *entries, unsigned value);
+static void dx_set_limit(struct dx_entry *entries, unsigned value);
+static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
+static unsigned dx_node_limit(struct inode *dir);
+static struct dx_frame *dx_probe(struct ext4_filename *fname,
+ struct inode *dir,
+ struct dx_hash_info *hinfo,
+ struct dx_frame *frame);
+static void dx_release(struct dx_frame *frames);
+static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
+ unsigned blocksize, struct dx_hash_info *hinfo,
+ struct dx_map_entry map[]);
+static void dx_sort_map(struct dx_map_entry *map, unsigned count);
+static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
+ struct dx_map_entry *offsets, int count, unsigned blocksize);
+static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
+static void dx_insert_block(struct dx_frame *frame,
+ u32 hash, ext4_lblk_t block);
+static int ext4_htree_next_block(struct inode *dir, __u32 hash,
+ struct dx_frame *frame,
+ struct dx_frame *frames,
+ __u32 *start_hash);
+static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
+ struct ext4_filename *fname,
+ struct ext4_dir_entry_2 **res_dir);
+static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
+ struct inode *dir, struct inode *inode);
+
+/* checksumming functions */
+void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
+ unsigned int blocksize)
+{
+ memset(t, 0, sizeof(struct ext4_dir_entry_tail));
+ t->det_rec_len = ext4_rec_len_to_disk(
+ sizeof(struct ext4_dir_entry_tail), blocksize);
+ t->det_reserved_ft = EXT4_FT_DIR_CSUM;
+}
+
+/* Walk through a dirent block to find a checksum "dirent" at the tail */
+static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
+ struct ext4_dir_entry *de)
+{
+ struct ext4_dir_entry_tail *t;
+
+#ifdef PARANOID
+ struct ext4_dir_entry *d, *top;
+
+ d = de;
+ top = (struct ext4_dir_entry *)(((void *)de) +
+ (EXT4_BLOCK_SIZE(inode->i_sb) -
+ sizeof(struct ext4_dir_entry_tail)));
+ while (d < top && d->rec_len)
+ d = (struct ext4_dir_entry *)(((void *)d) +
+ le16_to_cpu(d->rec_len));
+
+ if (d != top)
+ return NULL;
+
+ t = (struct ext4_dir_entry_tail *)d;
+#else
+ t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb));
+#endif
+
+ if (t->det_reserved_zero1 ||
+ le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
+ t->det_reserved_zero2 ||
+ t->det_reserved_ft != EXT4_FT_DIR_CSUM)
+ return NULL;
+
+ return t;
+}
+
+static __le32 ext4_dirent_csum(struct inode *inode,
+ struct ext4_dir_entry *dirent, int size)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ __u32 csum;
+
+ csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
+ return cpu_to_le32(csum);
+}
+
+#define warn_no_space_for_csum(inode) \
+ __warn_no_space_for_csum((inode), __func__, __LINE__)
+
+static void __warn_no_space_for_csum(struct inode *inode, const char *func,
+ unsigned int line)
+{
+ __ext4_warning_inode(inode, func, line,
+ "No space for directory leaf checksum. Please run e2fsck -D.");
+}
+
+int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent)
+{
+ struct ext4_dir_entry_tail *t;
+
+ if (!ext4_has_metadata_csum(inode->i_sb))
+ return 1;
+
+ t = get_dirent_tail(inode, dirent);
+ if (!t) {
+ warn_no_space_for_csum(inode);
+ return 0;
+ }
+
+ if (t->det_checksum != ext4_dirent_csum(inode, dirent,
+ (void *)t - (void *)dirent))
+ return 0;
+
+ return 1;
+}
+
+static void ext4_dirent_csum_set(struct inode *inode,
+ struct ext4_dir_entry *dirent)
+{
+ struct ext4_dir_entry_tail *t;
+
+ if (!ext4_has_metadata_csum(inode->i_sb))
+ return;
+
+ t = get_dirent_tail(inode, dirent);
+ if (!t) {
+ warn_no_space_for_csum(inode);
+ return;
+ }
+
+ t->det_checksum = ext4_dirent_csum(inode, dirent,
+ (void *)t - (void *)dirent);
+}
+
+int ext4_handle_dirty_dirent_node(handle_t *handle,
+ struct inode *inode,
+ struct buffer_head *bh)
+{
+ ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
+ return ext4_handle_dirty_metadata(handle, inode, bh);
+}
+
+static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
+ struct ext4_dir_entry *dirent,
+ int *offset)
+{
+ struct ext4_dir_entry *dp;
+ struct dx_root_info *root;
+ int count_offset;
+
+ if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
+ count_offset = 8;
+ else if (le16_to_cpu(dirent->rec_len) == 12) {
+ dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
+ if (le16_to_cpu(dp->rec_len) !=
+ EXT4_BLOCK_SIZE(inode->i_sb) - 12)
+ return NULL;
+ root = (struct dx_root_info *)(((void *)dp + 12));
+ if (root->reserved_zero ||
+ root->info_length != sizeof(struct dx_root_info))
+ return NULL;
+ count_offset = 32;
+ } else
+ return NULL;
+
+ if (offset)
+ *offset = count_offset;
+ return (struct dx_countlimit *)(((void *)dirent) + count_offset);
+}
+
+static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,
+ int count_offset, int count, struct dx_tail *t)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ __u32 csum;
+ int size;
+ __u32 dummy_csum = 0;
+ int offset = offsetof(struct dx_tail, dt_checksum);
+
+ size = count_offset + (count * sizeof(struct dx_entry));
+ csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
+ csum = ext4_chksum(sbi, csum, (__u8 *)t, offset);
+ csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum));
+
+ return cpu_to_le32(csum);
+}
+
+static int ext4_dx_csum_verify(struct inode *inode,
+ struct ext4_dir_entry *dirent)
+{
+ struct dx_countlimit *c;
+ struct dx_tail *t;
+ int count_offset, limit, count;
+
+ if (!ext4_has_metadata_csum(inode->i_sb))
+ return 1;
+
+ c = get_dx_countlimit(inode, dirent, &count_offset);
+ if (!c) {
+ EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
+ return 0;
+ }
+ limit = le16_to_cpu(c->limit);
+ count = le16_to_cpu(c->count);
+ if (count_offset + (limit * sizeof(struct dx_entry)) >
+ EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
+ warn_no_space_for_csum(inode);
+ return 0;
+ }
+ t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
+
+ if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,
+ count, t))
+ return 0;
+ return 1;
+}
+
+static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)
+{
+ struct dx_countlimit *c;
+ struct dx_tail *t;
+ int count_offset, limit, count;
+
+ if (!ext4_has_metadata_csum(inode->i_sb))
+ return;
+
+ c = get_dx_countlimit(inode, dirent, &count_offset);
+ if (!c) {
+ EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
+ return;
+ }
+ limit = le16_to_cpu(c->limit);
+ count = le16_to_cpu(c->count);
+ if (count_offset + (limit * sizeof(struct dx_entry)) >
+ EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
+ warn_no_space_for_csum(inode);
+ return;
+ }
+ t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
+
+ t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);
+}
+
+static inline int ext4_handle_dirty_dx_node(handle_t *handle,
+ struct inode *inode,
+ struct buffer_head *bh)
+{
+ ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
+ return ext4_handle_dirty_metadata(handle, inode, bh);
+}
+
+/*
+ * p is at least 6 bytes before the end of page
+ */
+static inline struct ext4_dir_entry_2 *
+ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
+{
+ return (struct ext4_dir_entry_2 *)((char *)p +
+ ext4_rec_len_from_disk(p->rec_len, blocksize));
+}
+
+/*
+ * Future: use high four bits of block for coalesce-on-delete flags
+ * Mask them off for now.
+ */
+
+static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)
+{
+ return le32_to_cpu(entry->block) & 0x0fffffff;
+}
+
+static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)
+{
+ entry->block = cpu_to_le32(value);
+}
+
+static inline unsigned dx_get_hash(struct dx_entry *entry)
+{
+ return le32_to_cpu(entry->hash);
+}
+
+static inline void dx_set_hash(struct dx_entry *entry, unsigned value)
+{
+ entry->hash = cpu_to_le32(value);
+}
+
+static inline unsigned dx_get_count(struct dx_entry *entries)
+{
+ return le16_to_cpu(((struct dx_countlimit *) entries)->count);
+}
+
+static inline unsigned dx_get_limit(struct dx_entry *entries)
+{
+ return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
+}
+
+static inline void dx_set_count(struct dx_entry *entries, unsigned value)
+{
+ ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
+}
+
+static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
+{
+ ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
+}
+
+static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
+{
+ unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
+ EXT4_DIR_REC_LEN(2) - infosize;
+
+ if (ext4_has_metadata_csum(dir->i_sb))
+ entry_space -= sizeof(struct dx_tail);
+ return entry_space / sizeof(struct dx_entry);
+}
+
+static inline unsigned dx_node_limit(struct inode *dir)
+{
+ unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
+
+ if (ext4_has_metadata_csum(dir->i_sb))
+ entry_space -= sizeof(struct dx_tail);
+ return entry_space / sizeof(struct dx_entry);
+}
+
+/*
+ * Debug
+ */
+#ifdef DX_DEBUG
+static void dx_show_index(char * label, struct dx_entry *entries)
+{
+ int i, n = dx_get_count (entries);
+ printk(KERN_DEBUG "%s index", label);
+ for (i = 0; i < n; i++) {
+ printk(KERN_CONT " %x->%lu",
+ i ? dx_get_hash(entries + i) : 0,
+ (unsigned long)dx_get_block(entries + i));
+ }
+ printk(KERN_CONT "\n");
+}
+
+struct stats
+{
+ unsigned names;
+ unsigned space;
+ unsigned bcount;
+};
+
+static struct stats dx_show_leaf(struct inode *dir,
+ struct dx_hash_info *hinfo,
+ struct ext4_dir_entry_2 *de,
+ int size, int show_names)
+{
+ unsigned names = 0, space = 0;
+ char *base = (char *) de;
+ struct dx_hash_info h = *hinfo;
+
+ printk("names: ");
+ while ((char *) de < base + size)
+ {
+ if (de->inode)
+ {
+ if (show_names)
+ {
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+ int len;
+ char *name;
+ struct fscrypt_str fname_crypto_str =
+ FSTR_INIT(NULL, 0);
+ int res = 0;
+
+ name = de->name;
+ len = de->name_len;
+ if (ext4_encrypted_inode(dir))
+ res = fscrypt_get_encryption_info(dir);
+ if (res) {
+ printk(KERN_WARNING "Error setting up"
+ " fname crypto: %d\n", res);
+ }
+ if (!fscrypt_has_encryption_key(dir)) {
+ /* Directory is not encrypted */
+ ext4fs_dirhash(de->name,
+ de->name_len, &h);
+ printk("%*.s:(U)%x.%u ", len,
+ name, h.hash,
+ (unsigned) ((char *) de
+ - base));
+ } else {
+ struct fscrypt_str de_name =
+ FSTR_INIT(name, len);
+
+ /* Directory is encrypted */
+ res = fscrypt_fname_alloc_buffer(
+ dir, len,
+ &fname_crypto_str);
+ if (res)
+ printk(KERN_WARNING "Error "
+ "allocating crypto "
+ "buffer--skipping "
+ "crypto\n");
+ res = fscrypt_fname_disk_to_usr(dir,
+ 0, 0, &de_name,
+ &fname_crypto_str);
+ if (res) {
+ printk(KERN_WARNING "Error "
+ "converting filename "
+ "from disk to usr"
+ "\n");
+ name = "??";
+ len = 2;
+ } else {
+ name = fname_crypto_str.name;
+ len = fname_crypto_str.len;
+ }
+ ext4fs_dirhash(de->name, de->name_len,
+ &h);
+ printk("%*.s:(E)%x.%u ", len, name,
+ h.hash, (unsigned) ((char *) de
+ - base));
+ fscrypt_fname_free_buffer(
+ &fname_crypto_str);
+ }
+#else
+ int len = de->name_len;
+ char *name = de->name;
+ ext4fs_dirhash(de->name, de->name_len, &h);
+ printk("%*.s:%x.%u ", len, name, h.hash,
+ (unsigned) ((char *) de - base));
+#endif
+ }
+ space += EXT4_DIR_REC_LEN(de->name_len);
+ names++;
+ }
+ de = ext4_next_entry(de, size);
+ }
+ printk(KERN_CONT "(%i)\n", names);
+ return (struct stats) { names, space, 1 };
+}
+
+struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
+ struct dx_entry *entries, int levels)
+{
+ unsigned blocksize = dir->i_sb->s_blocksize;
+ unsigned count = dx_get_count(entries), names = 0, space = 0, i;
+ unsigned bcount = 0;
+ struct buffer_head *bh;
+ printk("%i indexed blocks...\n", count);
+ for (i = 0; i < count; i++, entries++)
+ {
+ ext4_lblk_t block = dx_get_block(entries);
+ ext4_lblk_t hash = i ? dx_get_hash(entries): 0;
+ u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
+ struct stats stats;
+ printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
+ bh = ext4_bread(NULL,dir, block, 0);
+ if (!bh || IS_ERR(bh))
+ continue;
+ stats = levels?
+ dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
+ dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *)
+ bh->b_data, blocksize, 0);
+ names += stats.names;
+ space += stats.space;
+ bcount += stats.bcount;
+ brelse(bh);
+ }
+ if (bcount)
+ printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",
+ levels ? "" : " ", names, space/bcount,
+ (space/bcount)*100/blocksize);
+ return (struct stats) { names, space, bcount};
+}
+#endif /* DX_DEBUG */
+
+/*
+ * Probe for a directory leaf block to search.
+ *
+ * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
+ * error in the directory index, and the caller should fall back to
+ * searching the directory normally. The callers of dx_probe **MUST**
+ * check for this error code, and make sure it never gets reflected
+ * back to userspace.
+ */
+static struct dx_frame *
+dx_probe(struct ext4_filename *fname, struct inode *dir,
+ struct dx_hash_info *hinfo, struct dx_frame *frame_in)
+{
+ unsigned count, indirect;
+ struct dx_entry *at, *entries, *p, *q, *m;
+ struct dx_root *root;
+ struct dx_frame *frame = frame_in;
+ struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR);
+ u32 hash;
+
+ memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0]));
+ frame->bh = ext4_read_dirblock(dir, 0, INDEX);
+ if (IS_ERR(frame->bh))
+ return (struct dx_frame *) frame->bh;
+
+ root = (struct dx_root *) frame->bh->b_data;
+ if (root->info.hash_version != DX_HASH_TEA &&
+ root->info.hash_version != DX_HASH_HALF_MD4 &&
+ root->info.hash_version != DX_HASH_LEGACY) {
+ ext4_warning_inode(dir, "Unrecognised inode hash code %u",
+ root->info.hash_version);
+ goto fail;
+ }
+ if (fname)
+ hinfo = &fname->hinfo;
+ hinfo->hash_version = root->info.hash_version;
+ if (hinfo->hash_version <= DX_HASH_TEA)
+ hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
+ hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
+ if (fname && fname_name(fname))
+ ext4fs_dirhash(fname_name(fname), fname_len(fname), hinfo);
+ hash = hinfo->hash;
+
+ if (root->info.unused_flags & 1) {
+ ext4_warning_inode(dir, "Unimplemented hash flags: %#06x",
+ root->info.unused_flags);
+ goto fail;
+ }
+
+ indirect = root->info.indirect_levels;
+ if (indirect >= ext4_dir_htree_level(dir->i_sb)) {
+ ext4_warning(dir->i_sb,
+ "Directory (ino: %lu) htree depth %#06x exceed"
+ "supported value", dir->i_ino,
+ ext4_dir_htree_level(dir->i_sb));
+ if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) {
+ ext4_warning(dir->i_sb, "Enable large directory "
+ "feature to access it");
+ }
+ goto fail;
+ }
+
+ entries = (struct dx_entry *)(((char *)&root->info) +
+ root->info.info_length);
+
+ if (dx_get_limit(entries) != dx_root_limit(dir,
+ root->info.info_length)) {
+ ext4_warning_inode(dir, "dx entry: limit %u != root limit %u",
+ dx_get_limit(entries),
+ dx_root_limit(dir, root->info.info_length));
+ goto fail;
+ }
+
+ dxtrace(printk("Look up %x", hash));
+ while (1) {
+ count = dx_get_count(entries);
+ if (!count || count > dx_get_limit(entries)) {
+ ext4_warning_inode(dir,
+ "dx entry: count %u beyond limit %u",
+ count, dx_get_limit(entries));
+ goto fail;
+ }
+
+ p = entries + 1;
+ q = entries + count - 1;
+ while (p <= q) {
+ m = p + (q - p) / 2;
+ dxtrace(printk(KERN_CONT "."));
+ if (dx_get_hash(m) > hash)
+ q = m - 1;
+ else
+ p = m + 1;
+ }
+
+ if (0) { // linear search cross check
+ unsigned n = count - 1;
+ at = entries;
+ while (n--)
+ {
+ dxtrace(printk(KERN_CONT ","));
+ if (dx_get_hash(++at) > hash)
+ {
+ at--;
+ break;
+ }
+ }
+ assert (at == p - 1);
+ }
+
+ at = p - 1;
+ dxtrace(printk(KERN_CONT " %x->%u\n",
+ at == entries ? 0 : dx_get_hash(at),
+ dx_get_block(at)));
+ frame->entries = entries;
+ frame->at = at;
+ if (!indirect--)
+ return frame;
+ frame++;
+ frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX);
+ if (IS_ERR(frame->bh)) {
+ ret_err = (struct dx_frame *) frame->bh;
+ frame->bh = NULL;
+ goto fail;
+ }
+ entries = ((struct dx_node *) frame->bh->b_data)->entries;
+
+ if (dx_get_limit(entries) != dx_node_limit(dir)) {
+ ext4_warning_inode(dir,
+ "dx entry: limit %u != node limit %u",
+ dx_get_limit(entries), dx_node_limit(dir));
+ goto fail;
+ }
+ }
+fail:
+ while (frame >= frame_in) {
+ brelse(frame->bh);
+ frame--;
+ }
+
+ if (ret_err == ERR_PTR(ERR_BAD_DX_DIR))
+ ext4_warning_inode(dir,
+ "Corrupt directory, running e2fsck is recommended");
+ return ret_err;
+}
+
+static void dx_release(struct dx_frame *frames)
+{
+ struct dx_root_info *info;
+ int i;
+
+ if (frames[0].bh == NULL)
+ return;
+
+ info = &((struct dx_root *)frames[0].bh->b_data)->info;
+ for (i = 0; i <= info->indirect_levels; i++) {
+ if (frames[i].bh == NULL)
+ break;
+ brelse(frames[i].bh);
+ frames[i].bh = NULL;
+ }
+}
+
+/*
+ * This function increments the frame pointer to search the next leaf
+ * block, and reads in the necessary intervening nodes if the search
+ * should be necessary. Whether or not the search is necessary is
+ * controlled by the hash parameter. If the hash value is even, then
+ * the search is only continued if the next block starts with that
+ * hash value. This is used if we are searching for a specific file.
+ *
+ * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
+ *
+ * This function returns 1 if the caller should continue to search,
+ * or 0 if it should not. If there is an error reading one of the
+ * index blocks, it will a negative error code.
+ *
+ * If start_hash is non-null, it will be filled in with the starting
+ * hash of the next page.
+ */
+static int ext4_htree_next_block(struct inode *dir, __u32 hash,
+ struct dx_frame *frame,
+ struct dx_frame *frames,
+ __u32 *start_hash)
+{
+ struct dx_frame *p;
+ struct buffer_head *bh;
+ int num_frames = 0;
+ __u32 bhash;
+
+ p = frame;
+ /*
+ * Find the next leaf page by incrementing the frame pointer.
+ * If we run out of entries in the interior node, loop around and
+ * increment pointer in the parent node. When we break out of
+ * this loop, num_frames indicates the number of interior
+ * nodes need to be read.
+ */
+ while (1) {
+ if (++(p->at) < p->entries + dx_get_count(p->entries))
+ break;
+ if (p == frames)
+ return 0;
+ num_frames++;
+ p--;
+ }
+
+ /*
+ * If the hash is 1, then continue only if the next page has a
+ * continuation hash of any value. This is used for readdir
+ * handling. Otherwise, check to see if the hash matches the
+ * desired contiuation hash. If it doesn't, return since
+ * there's no point to read in the successive index pages.
+ */
+ bhash = dx_get_hash(p->at);
+ if (start_hash)
+ *start_hash = bhash;
+ if ((hash & 1) == 0) {
+ if ((bhash & ~1) != hash)
+ return 0;
+ }
+ /*
+ * If the hash is HASH_NB_ALWAYS, we always go to the next
+ * block so no check is necessary
+ */
+ while (num_frames--) {
+ bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX);
+ if (IS_ERR(bh))
+ return PTR_ERR(bh);
+ p++;
+ brelse(p->bh);
+ p->bh = bh;
+ p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
+ }
+ return 1;
+}
+
+
+/*
+ * This function fills a red-black tree with information from a
+ * directory block. It returns the number directory entries loaded
+ * into the tree. If there is an error it is returned in err.
+ */
+static int htree_dirblock_to_tree(struct file *dir_file,
+ struct inode *dir, ext4_lblk_t block,
+ struct dx_hash_info *hinfo,
+ __u32 start_hash, __u32 start_minor_hash)
+{
+ struct buffer_head *bh;
+ struct ext4_dir_entry_2 *de, *top;
+ int err = 0, count = 0;
+ struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str;
+
+ dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
+ (unsigned long)block));
+ bh = ext4_read_dirblock(dir, block, DIRENT);
+ if (IS_ERR(bh))
+ return PTR_ERR(bh);
+
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ top = (struct ext4_dir_entry_2 *) ((char *) de +
+ dir->i_sb->s_blocksize -
+ EXT4_DIR_REC_LEN(0));
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+ /* Check if the directory is encrypted */
+ if (ext4_encrypted_inode(dir)) {
+ err = fscrypt_get_encryption_info(dir);
+ if (err < 0) {
+ brelse(bh);
+ return err;
+ }
+ err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN,
+ &fname_crypto_str);
+ if (err < 0) {
+ brelse(bh);
+ return err;
+ }
+ }
+#endif
+ for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
+ if (ext4_check_dir_entry(dir, NULL, de, bh,
+ bh->b_data, bh->b_size,
+ (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
+ + ((char *)de - bh->b_data))) {
+ /* silently ignore the rest of the block */
+ break;
+ }
+ ext4fs_dirhash(de->name, de->name_len, hinfo);
+ if ((hinfo->hash < start_hash) ||
+ ((hinfo->hash == start_hash) &&
+ (hinfo->minor_hash < start_minor_hash)))
+ continue;
+ if (de->inode == 0)
+ continue;
+ if (!ext4_encrypted_inode(dir)) {
+ tmp_str.name = de->name;
+ tmp_str.len = de->name_len;
+ err = ext4_htree_store_dirent(dir_file,
+ hinfo->hash, hinfo->minor_hash, de,
+ &tmp_str);
+ } else {
+ int save_len = fname_crypto_str.len;
+ struct fscrypt_str de_name = FSTR_INIT(de->name,
+ de->name_len);
+
+ /* Directory is encrypted */
+ err = fscrypt_fname_disk_to_usr(dir, hinfo->hash,
+ hinfo->minor_hash, &de_name,
+ &fname_crypto_str);
+ if (err) {
+ count = err;
+ goto errout;
+ }
+ err = ext4_htree_store_dirent(dir_file,
+ hinfo->hash, hinfo->minor_hash, de,
+ &fname_crypto_str);
+ fname_crypto_str.len = save_len;
+ }
+ if (err != 0) {
+ count = err;
+ goto errout;
+ }
+ count++;
+ }
+errout:
+ brelse(bh);
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+ fscrypt_fname_free_buffer(&fname_crypto_str);
+#endif
+ return count;
+}
+
+
+/*
+ * This function fills a red-black tree with information from a
+ * directory. We start scanning the directory in hash order, starting
+ * at start_hash and start_minor_hash.
+ *
+ * This function returns the number of entries inserted into the tree,
+ * or a negative error code.
+ */
+int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
+ __u32 start_minor_hash, __u32 *next_hash)
+{
+ struct dx_hash_info hinfo;
+ struct ext4_dir_entry_2 *de;
+ struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
+ struct inode *dir;
+ ext4_lblk_t block;
+ int count = 0;
+ int ret, err;
+ __u32 hashval;
+ struct fscrypt_str tmp_str;
+
+ dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
+ start_hash, start_minor_hash));
+ dir = file_inode(dir_file);
+ if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) {
+ hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
+ if (hinfo.hash_version <= DX_HASH_TEA)
+ hinfo.hash_version +=
+ EXT4_SB(dir->i_sb)->s_hash_unsigned;
+ hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
+ if (ext4_has_inline_data(dir)) {
+ int has_inline_data = 1;
+ count = htree_inlinedir_to_tree(dir_file, dir, 0,
+ &hinfo, start_hash,
+ start_minor_hash,
+ &has_inline_data);
+ if (has_inline_data) {
+ *next_hash = ~0;
+ return count;
+ }
+ }
+ count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
+ start_hash, start_minor_hash);
+ *next_hash = ~0;
+ return count;
+ }
+ hinfo.hash = start_hash;
+ hinfo.minor_hash = 0;
+ frame = dx_probe(NULL, dir, &hinfo, frames);
+ if (IS_ERR(frame))
+ return PTR_ERR(frame);
+
+ /* Add '.' and '..' from the htree header */
+ if (!start_hash && !start_minor_hash) {
+ de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
+ tmp_str.name = de->name;
+ tmp_str.len = de->name_len;
+ err = ext4_htree_store_dirent(dir_file, 0, 0,
+ de, &tmp_str);
+ if (err != 0)
+ goto errout;
+ count++;
+ }
+ if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
+ de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
+ de = ext4_next_entry(de, dir->i_sb->s_blocksize);
+ tmp_str.name = de->name;
+ tmp_str.len = de->name_len;
+ err = ext4_htree_store_dirent(dir_file, 2, 0,
+ de, &tmp_str);
+ if (err != 0)
+ goto errout;
+ count++;
+ }
+
+ while (1) {
+ if (fatal_signal_pending(current)) {
+ err = -ERESTARTSYS;
+ goto errout;
+ }
+ cond_resched();
+ block = dx_get_block(frame->at);
+ ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
+ start_hash, start_minor_hash);
+ if (ret < 0) {
+ err = ret;
+ goto errout;
+ }
+ count += ret;
+ hashval = ~0;
+ ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
+ frame, frames, &hashval);
+ *next_hash = hashval;
+ if (ret < 0) {
+ err = ret;
+ goto errout;
+ }
+ /*
+ * Stop if: (a) there are no more entries, or
+ * (b) we have inserted at least one entry and the
+ * next hash value is not a continuation
+ */
+ if ((ret == 0) ||
+ (count && ((hashval & 1) == 0)))
+ break;
+ }
+ dx_release(frames);
+ dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "
+ "next hash: %x\n", count, *next_hash));
+ return count;
+errout:
+ dx_release(frames);
+ return (err);
+}
+
+static inline int search_dirblock(struct buffer_head *bh,
+ struct inode *dir,
+ struct ext4_filename *fname,
+ unsigned int offset,
+ struct ext4_dir_entry_2 **res_dir)
+{
+ return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir,
+ fname, offset, res_dir);
+}
+
+/*
+ * Directory block splitting, compacting
+ */
+
+/*
+ * Create map of hash values, offsets, and sizes, stored at end of block.
+ * Returns number of entries mapped.
+ */
+static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
+ unsigned blocksize, struct dx_hash_info *hinfo,
+ struct dx_map_entry *map_tail)
+{
+ int count = 0;
+ char *base = (char *) de;
+ struct dx_hash_info h = *hinfo;
+
+ while ((char *) de < base + blocksize) {
+ if (de->name_len && de->inode) {
+ ext4fs_dirhash(de->name, de->name_len, &h);
+ map_tail--;
+ map_tail->hash = h.hash;
+ map_tail->offs = ((char *) de - base)>>2;
+ map_tail->size = le16_to_cpu(de->rec_len);
+ count++;
+ cond_resched();
+ }
+ /* XXX: do we need to check rec_len == 0 case? -Chris */
+ de = ext4_next_entry(de, blocksize);
+ }
+ return count;
+}
+
+/* Sort map by hash value */
+static void dx_sort_map (struct dx_map_entry *map, unsigned count)
+{
+ struct dx_map_entry *p, *q, *top = map + count - 1;
+ int more;
+ /* Combsort until bubble sort doesn't suck */
+ while (count > 2) {
+ count = count*10/13;
+ if (count - 9 < 2) /* 9, 10 -> 11 */
+ count = 11;
+ for (p = top, q = p - count; q >= map; p--, q--)
+ if (p->hash < q->hash)
+ swap(*p, *q);
+ }
+ /* Garden variety bubble sort */
+ do {
+ more = 0;
+ q = top;
+ while (q-- > map) {
+ if (q[1].hash >= q[0].hash)
+ continue;
+ swap(*(q+1), *q);
+ more = 1;
+ }
+ } while(more);
+}
+
+static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
+{
+ struct dx_entry *entries = frame->entries;
+ struct dx_entry *old = frame->at, *new = old + 1;
+ int count = dx_get_count(entries);
+
+ assert(count < dx_get_limit(entries));
+ assert(old < entries + count);
+ memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
+ dx_set_hash(new, hash);
+ dx_set_block(new, block);
+ dx_set_count(entries, count + 1);
+}
+
+/*
+ * Test whether a directory entry matches the filename being searched for.
+ *
+ * Return: %true if the directory entry matches, otherwise %false.
+ */
+static inline bool ext4_match(const struct ext4_filename *fname,
+ const struct ext4_dir_entry_2 *de)
+{
+ struct fscrypt_name f;
+
+ if (!de->inode)
+ return false;
+
+ f.usr_fname = fname->usr_fname;
+ f.disk_name = fname->disk_name;
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+ f.crypto_buf = fname->crypto_buf;
+#endif
+ return fscrypt_match_name(&f, de->name, de->name_len);
+}
+
+/*
+ * Returns 0 if not found, -1 on failure, and 1 on success
+ */
+int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size,
+ struct inode *dir, struct ext4_filename *fname,
+ unsigned int offset, struct ext4_dir_entry_2 **res_dir)
+{
+ struct ext4_dir_entry_2 * de;
+ char * dlimit;
+ int de_len;
+
+ de = (struct ext4_dir_entry_2 *)search_buf;
+ dlimit = search_buf + buf_size;
+ while ((char *) de < dlimit) {
+ /* this code is executed quadratically often */
+ /* do minimal checking `by hand' */
+ if ((char *) de + de->name_len <= dlimit &&
+ ext4_match(fname, de)) {
+ /* found a match - just to be sure, do
+ * a full check */
+ if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data,
+ bh->b_size, offset))
+ return -1;
+ *res_dir = de;
+ return 1;
+ }
+ /* prevent looping on a bad block */
+ de_len = ext4_rec_len_from_disk(de->rec_len,
+ dir->i_sb->s_blocksize);
+ if (de_len <= 0)
+ return -1;
+ offset += de_len;
+ de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
+ }
+ return 0;
+}
+
+static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block,
+ struct ext4_dir_entry *de)
+{
+ struct super_block *sb = dir->i_sb;
+
+ if (!is_dx(dir))
+ return 0;
+ if (block == 0)
+ return 1;
+ if (de->inode == 0 &&
+ ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) ==
+ sb->s_blocksize)
+ return 1;
+ return 0;
+}
+
+/*
+ * ext4_find_entry()
+ *
+ * finds an entry in the specified directory with the wanted name. It
+ * returns the cache buffer in which the entry was found, and the entry
+ * itself (as a parameter - res_dir). It does NOT read the inode of the
+ * entry - you'll have to do that yourself if you want to.
+ *
+ * The returned buffer_head has ->b_count elevated. The caller is expected
+ * to brelse() it when appropriate.
+ */
+static struct buffer_head * ext4_find_entry (struct inode *dir,
+ const struct qstr *d_name,
+ struct ext4_dir_entry_2 **res_dir,
+ int *inlined)
+{
+ struct super_block *sb;
+ struct buffer_head *bh_use[NAMEI_RA_SIZE];
+ struct buffer_head *bh, *ret = NULL;
+ ext4_lblk_t start, block;
+ const u8 *name = d_name->name;
+ size_t ra_max = 0; /* Number of bh's in the readahead
+ buffer, bh_use[] */
+ size_t ra_ptr = 0; /* Current index into readahead
+ buffer */
+ ext4_lblk_t nblocks;
+ int i, namelen, retval;
+ struct ext4_filename fname;
+
+ *res_dir = NULL;
+ sb = dir->i_sb;
+ namelen = d_name->len;
+ if (namelen > EXT4_NAME_LEN)
+ return NULL;
+
+ retval = ext4_fname_setup_filename(dir, d_name, 1, &fname);
+ if (retval == -ENOENT)
+ return NULL;
+ if (retval)
+ return ERR_PTR(retval);
+
+ if (ext4_has_inline_data(dir)) {
+ int has_inline_data = 1;
+ ret = ext4_find_inline_entry(dir, &fname, res_dir,
+ &has_inline_data);
+ if (has_inline_data) {
+ if (inlined)
+ *inlined = 1;
+ goto cleanup_and_exit;
+ }
+ }
+
+ if ((namelen <= 2) && (name[0] == '.') &&
+ (name[1] == '.' || name[1] == '\0')) {
+ /*
+ * "." or ".." will only be in the first block
+ * NFS may look up ".."; "." should be handled by the VFS
+ */
+ block = start = 0;
+ nblocks = 1;
+ goto restart;
+ }
+ if (is_dx(dir)) {
+ ret = ext4_dx_find_entry(dir, &fname, res_dir);
+ /*
+ * On success, or if the error was file not found,
+ * return. Otherwise, fall back to doing a search the
+ * old fashioned way.
+ */
+ if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR)
+ goto cleanup_and_exit;
+ dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "
+ "falling back\n"));
+ ret = NULL;
+ }
+ nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
+ if (!nblocks) {
+ ret = NULL;
+ goto cleanup_and_exit;
+ }
+ start = EXT4_I(dir)->i_dir_start_lookup;
+ if (start >= nblocks)
+ start = 0;
+ block = start;
+restart:
+ do {
+ /*
+ * We deal with the read-ahead logic here.
+ */
+ if (ra_ptr >= ra_max) {
+ /* Refill the readahead buffer */
+ ra_ptr = 0;
+ if (block < start)
+ ra_max = start - block;
+ else
+ ra_max = nblocks - block;
+ ra_max = min(ra_max, ARRAY_SIZE(bh_use));
+ retval = ext4_bread_batch(dir, block, ra_max,
+ false /* wait */, bh_use);
+ if (retval) {
+ ret = ERR_PTR(retval);
+ ra_max = 0;
+ goto cleanup_and_exit;
+ }
+ }
+ if ((bh = bh_use[ra_ptr++]) == NULL)
+ goto next;
+ wait_on_buffer(bh);
+ if (!buffer_uptodate(bh)) {
+ EXT4_ERROR_INODE(dir, "reading directory lblock %lu",
+ (unsigned long) block);
+ brelse(bh);
+ ret = ERR_PTR(-EIO);
+ goto cleanup_and_exit;
+ }
+ if (!buffer_verified(bh) &&
+ !is_dx_internal_node(dir, block,
+ (struct ext4_dir_entry *)bh->b_data) &&
+ !ext4_dirent_csum_verify(dir,
+ (struct ext4_dir_entry *)bh->b_data)) {
+ EXT4_ERROR_INODE(dir, "checksumming directory "
+ "block %lu", (unsigned long)block);
+ brelse(bh);
+ ret = ERR_PTR(-EFSBADCRC);
+ goto cleanup_and_exit;
+ }
+ set_buffer_verified(bh);
+ i = search_dirblock(bh, dir, &fname,
+ block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
+ if (i == 1) {
+ EXT4_I(dir)->i_dir_start_lookup = block;
+ ret = bh;
+ goto cleanup_and_exit;
+ } else {
+ brelse(bh);
+ if (i < 0)
+ goto cleanup_and_exit;
+ }
+ next:
+ if (++block >= nblocks)
+ block = 0;
+ } while (block != start);
+
+ /*
+ * If the directory has grown while we were searching, then
+ * search the last part of the directory before giving up.
+ */
+ block = nblocks;
+ nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
+ if (block < nblocks) {
+ start = 0;
+ goto restart;
+ }
+
+cleanup_and_exit:
+ /* Clean up the read-ahead blocks */
+ for (; ra_ptr < ra_max; ra_ptr++)
+ brelse(bh_use[ra_ptr]);
+ ext4_fname_free_filename(&fname);
+ return ret;
+}
+
+static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
+ struct ext4_filename *fname,
+ struct ext4_dir_entry_2 **res_dir)
+{
+ struct super_block * sb = dir->i_sb;
+ struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
+ struct buffer_head *bh;
+ ext4_lblk_t block;
+ int retval;
+
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+ *res_dir = NULL;
+#endif
+ frame = dx_probe(fname, dir, NULL, frames);
+ if (IS_ERR(frame))
+ return (struct buffer_head *) frame;
+ do {
+ block = dx_get_block(frame->at);
+ bh = ext4_read_dirblock(dir, block, DIRENT);
+ if (IS_ERR(bh))
+ goto errout;
+
+ retval = search_dirblock(bh, dir, fname,
+ block << EXT4_BLOCK_SIZE_BITS(sb),
+ res_dir);
+ if (retval == 1)
+ goto success;
+ brelse(bh);
+ if (retval == -1) {
+ bh = ERR_PTR(ERR_BAD_DX_DIR);
+ goto errout;
+ }
+
+ /* Check to see if we should continue to search */
+ retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame,
+ frames, NULL);
+ if (retval < 0) {
+ ext4_warning_inode(dir,
+ "error %d reading directory index block",
+ retval);
+ bh = ERR_PTR(retval);
+ goto errout;
+ }
+ } while (retval == 1);
+
+ bh = NULL;
+errout:
+ dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name));
+success:
+ dx_release(frames);
+ return bh;
+}
+
+static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
+{
+ struct inode *inode;
+ struct ext4_dir_entry_2 *de;
+ struct buffer_head *bh;
+ int err;
+
+ err = fscrypt_prepare_lookup(dir, dentry, flags);
+ if (err)
+ return ERR_PTR(err);
+
+ if (dentry->d_name.len > EXT4_NAME_LEN)
+ return ERR_PTR(-ENAMETOOLONG);
+
+ bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
+ if (IS_ERR(bh))
+ return (struct dentry *) bh;
+ inode = NULL;
+ if (bh) {
+ __u32 ino = le32_to_cpu(de->inode);
+ brelse(bh);
+ if (!ext4_valid_inum(dir->i_sb, ino)) {
+ EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);
+ return ERR_PTR(-EFSCORRUPTED);
+ }
+ if (unlikely(ino == dir->i_ino)) {
+ EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir",
+ dentry);
+ return ERR_PTR(-EFSCORRUPTED);
+ }
+ inode = ext4_iget_normal(dir->i_sb, ino);
+ if (inode == ERR_PTR(-ESTALE)) {
+ EXT4_ERROR_INODE(dir,
+ "deleted inode referenced: %u",
+ ino);
+ return ERR_PTR(-EFSCORRUPTED);
+ }
+ if (!IS_ERR(inode) && ext4_encrypted_inode(dir) &&
+ (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
+ !fscrypt_has_permitted_context(dir, inode)) {
+ ext4_warning(inode->i_sb,
+ "Inconsistent encryption contexts: %lu/%lu",
+ dir->i_ino, inode->i_ino);
+ iput(inode);
+ return ERR_PTR(-EPERM);
+ }
+ }
+ return d_splice_alias(inode, dentry);
+}
+
+
+struct dentry *ext4_get_parent(struct dentry *child)
+{
+ __u32 ino;
+ static const struct qstr dotdot = QSTR_INIT("..", 2);
+ struct ext4_dir_entry_2 * de;
+ struct buffer_head *bh;
+
+ bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL);
+ if (IS_ERR(bh))
+ return (struct dentry *) bh;
+ if (!bh)
+ return ERR_PTR(-ENOENT);
+ ino = le32_to_cpu(de->inode);
+ brelse(bh);
+
+ if (!ext4_valid_inum(child->d_sb, ino)) {
+ EXT4_ERROR_INODE(d_inode(child),
+ "bad parent inode number: %u", ino);
+ return ERR_PTR(-EFSCORRUPTED);
+ }
+
+ return d_obtain_alias(ext4_iget_normal(child->d_sb, ino));
+}
+
+/*
+ * Move count entries from end of map between two memory locations.
+ * Returns pointer to last entry moved.
+ */
+static struct ext4_dir_entry_2 *
+dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
+ unsigned blocksize)
+{
+ unsigned rec_len = 0;
+
+ while (count--) {
+ struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
+ (from + (map->offs<<2));
+ rec_len = EXT4_DIR_REC_LEN(de->name_len);
+ memcpy (to, de, rec_len);
+ ((struct ext4_dir_entry_2 *) to)->rec_len =
+ ext4_rec_len_to_disk(rec_len, blocksize);
+ de->inode = 0;
+ map++;
+ to += rec_len;
+ }
+ return (struct ext4_dir_entry_2 *) (to - rec_len);
+}
+
+/*
+ * Compact each dir entry in the range to the minimal rec_len.
+ * Returns pointer to last entry in range.
+ */
+static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
+{
+ struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
+ unsigned rec_len = 0;
+
+ prev = to = de;
+ while ((char*)de < base + blocksize) {
+ next = ext4_next_entry(de, blocksize);
+ if (de->inode && de->name_len) {
+ rec_len = EXT4_DIR_REC_LEN(de->name_len);
+ if (de > to)
+ memmove(to, de, rec_len);
+ to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
+ prev = to;
+ to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
+ }
+ de = next;
+ }
+ return prev;
+}
+
+/*
+ * Split a full leaf block to make room for a new dir entry.
+ * Allocate a new block, and move entries so that they are approx. equally full.
+ * Returns pointer to de in block into which the new entry will be inserted.
+ */
+static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
+ struct buffer_head **bh,struct dx_frame *frame,
+ struct dx_hash_info *hinfo)
+{
+ unsigned blocksize = dir->i_sb->s_blocksize;
+ unsigned count, continued;
+ struct buffer_head *bh2;
+ ext4_lblk_t newblock;
+ u32 hash2;
+ struct dx_map_entry *map;
+ char *data1 = (*bh)->b_data, *data2;
+ unsigned split, move, size;
+ struct ext4_dir_entry_2 *de = NULL, *de2;
+ struct ext4_dir_entry_tail *t;
+ int csum_size = 0;
+ int err = 0, i;
+
+ if (ext4_has_metadata_csum(dir->i_sb))
+ csum_size = sizeof(struct ext4_dir_entry_tail);
+
+ bh2 = ext4_append(handle, dir, &newblock);
+ if (IS_ERR(bh2)) {
+ brelse(*bh);
+ *bh = NULL;
+ return (struct ext4_dir_entry_2 *) bh2;
+ }
+
+ BUFFER_TRACE(*bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, *bh);
+ if (err)
+ goto journal_error;
+
+ BUFFER_TRACE(frame->bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, frame->bh);
+ if (err)
+ goto journal_error;
+
+ data2 = bh2->b_data;
+
+ /* create map in the end of data2 block */
+ map = (struct dx_map_entry *) (data2 + blocksize);
+ count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1,
+ blocksize, hinfo, map);
+ map -= count;
+ dx_sort_map(map, count);
+ /* Split the existing block in the middle, size-wise */
+ size = 0;
+ move = 0;
+ for (i = count-1; i >= 0; i--) {
+ /* is more than half of this entry in 2nd half of the block? */
+ if (size + map[i].size/2 > blocksize/2)
+ break;
+ size += map[i].size;
+ move++;
+ }
+ /* map index at which we will split */
+ split = count - move;
+ hash2 = map[split].hash;
+ continued = hash2 == map[split - 1].hash;
+ dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
+ (unsigned long)dx_get_block(frame->at),
+ hash2, split, count-split));
+
+ /* Fancy dance to stay within two buffers */
+ de2 = dx_move_dirents(data1, data2, map + split, count - split,
+ blocksize);
+ de = dx_pack_dirents(data1, blocksize);
+ de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
+ (char *) de,
+ blocksize);
+ de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
+ (char *) de2,
+ blocksize);
+ if (csum_size) {
+ t = EXT4_DIRENT_TAIL(data2, blocksize);
+ initialize_dirent_tail(t, blocksize);
+
+ t = EXT4_DIRENT_TAIL(data1, blocksize);
+ initialize_dirent_tail(t, blocksize);
+ }
+
+ dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,
+ blocksize, 1));
+ dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2,
+ blocksize, 1));
+
+ /* Which block gets the new entry? */
+ if (hinfo->hash >= hash2) {
+ swap(*bh, bh2);
+ de = de2;
+ }
+ dx_insert_block(frame, hash2 + continued, newblock);
+ err = ext4_handle_dirty_dirent_node(handle, dir, bh2);
+ if (err)
+ goto journal_error;
+ err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
+ if (err)
+ goto journal_error;
+ brelse(bh2);
+ dxtrace(dx_show_index("frame", frame->entries));
+ return de;
+
+journal_error:
+ brelse(*bh);
+ brelse(bh2);
+ *bh = NULL;
+ ext4_std_error(dir->i_sb, err);
+ return ERR_PTR(err);
+}
+
+int ext4_find_dest_de(struct inode *dir, struct inode *inode,
+ struct buffer_head *bh,
+ void *buf, int buf_size,
+ struct ext4_filename *fname,
+ struct ext4_dir_entry_2 **dest_de)
+{
+ struct ext4_dir_entry_2 *de;
+ unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname));
+ int nlen, rlen;
+ unsigned int offset = 0;
+ char *top;
+
+ de = (struct ext4_dir_entry_2 *)buf;
+ top = buf + buf_size - reclen;
+ while ((char *) de <= top) {
+ if (ext4_check_dir_entry(dir, NULL, de, bh,
+ buf, buf_size, offset))
+ return -EFSCORRUPTED;
+ if (ext4_match(fname, de))
+ return -EEXIST;
+ nlen = EXT4_DIR_REC_LEN(de->name_len);
+ rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
+ if ((de->inode ? rlen - nlen : rlen) >= reclen)
+ break;
+ de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
+ offset += rlen;
+ }
+ if ((char *) de > top)
+ return -ENOSPC;
+
+ *dest_de = de;
+ return 0;
+}
+
+void ext4_insert_dentry(struct inode *inode,
+ struct ext4_dir_entry_2 *de,
+ int buf_size,
+ struct ext4_filename *fname)
+{
+
+ int nlen, rlen;
+
+ nlen = EXT4_DIR_REC_LEN(de->name_len);
+ rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
+ if (de->inode) {
+ struct ext4_dir_entry_2 *de1 =
+ (struct ext4_dir_entry_2 *)((char *)de + nlen);
+ de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size);
+ de->rec_len = ext4_rec_len_to_disk(nlen, buf_size);
+ de = de1;
+ }
+ de->file_type = EXT4_FT_UNKNOWN;
+ de->inode = cpu_to_le32(inode->i_ino);
+ ext4_set_de_type(inode->i_sb, de, inode->i_mode);
+ de->name_len = fname_len(fname);
+ memcpy(de->name, fname_name(fname), fname_len(fname));
+}
+
+/*
+ * Add a new entry into a directory (leaf) block. If de is non-NULL,
+ * it points to a directory entry which is guaranteed to be large
+ * enough for new directory entry. If de is NULL, then
+ * add_dirent_to_buf will attempt search the directory block for
+ * space. It will return -ENOSPC if no space is available, and -EIO
+ * and -EEXIST if directory entry already exists.
+ */
+static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
+ struct inode *dir,
+ struct inode *inode, struct ext4_dir_entry_2 *de,
+ struct buffer_head *bh)
+{
+ unsigned int blocksize = dir->i_sb->s_blocksize;
+ int csum_size = 0;
+ int err;
+
+ if (ext4_has_metadata_csum(inode->i_sb))
+ csum_size = sizeof(struct ext4_dir_entry_tail);
+
+ if (!de) {
+ err = ext4_find_dest_de(dir, inode, bh, bh->b_data,
+ blocksize - csum_size, fname, &de);
+ if (err)
+ return err;
+ }
+ BUFFER_TRACE(bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, bh);
+ if (err) {
+ ext4_std_error(dir->i_sb, err);
+ return err;
+ }
+
+ /* By now the buffer is marked for journaling */
+ ext4_insert_dentry(inode, de, blocksize, fname);
+
+ /*
+ * XXX shouldn't update any times until successful
+ * completion of syscall, but too many callers depend
+ * on this.
+ *
+ * XXX similarly, too many callers depend on
+ * ext4_new_inode() setting the times, but error
+ * recovery deletes the inode, so the worst that can
+ * happen is that the times are slightly out of date
+ * and/or different from the directory change time.
+ */
+ dir->i_mtime = dir->i_ctime = current_time(dir);
+ ext4_update_dx_flag(dir);
+ inode_inc_iversion(dir);
+ ext4_mark_inode_dirty(handle, dir);
+ BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_dirent_node(handle, dir, bh);
+ if (err)
+ ext4_std_error(dir->i_sb, err);
+ return 0;
+}
+
+/*
+ * This converts a one block unindexed directory to a 3 block indexed
+ * directory, and adds the dentry to the indexed directory.
+ */
+static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
+ struct inode *dir,
+ struct inode *inode, struct buffer_head *bh)
+{
+ struct buffer_head *bh2;
+ struct dx_root *root;
+ struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
+ struct dx_entry *entries;
+ struct ext4_dir_entry_2 *de, *de2;
+ struct ext4_dir_entry_tail *t;
+ char *data1, *top;
+ unsigned len;
+ int retval;
+ unsigned blocksize;
+ ext4_lblk_t block;
+ struct fake_dirent *fde;
+ int csum_size = 0;
+
+ if (ext4_has_metadata_csum(inode->i_sb))
+ csum_size = sizeof(struct ext4_dir_entry_tail);
+
+ blocksize = dir->i_sb->s_blocksize;
+ dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
+ BUFFER_TRACE(bh, "get_write_access");
+ retval = ext4_journal_get_write_access(handle, bh);
+ if (retval) {
+ ext4_std_error(dir->i_sb, retval);
+ brelse(bh);
+ return retval;
+ }
+ root = (struct dx_root *) bh->b_data;
+
+ /* The 0th block becomes the root, move the dirents out */
+ fde = &root->dotdot;
+ de = (struct ext4_dir_entry_2 *)((char *)fde +
+ ext4_rec_len_from_disk(fde->rec_len, blocksize));
+ if ((char *) de >= (((char *) root) + blocksize)) {
+ EXT4_ERROR_INODE(dir, "invalid rec_len for '..'");
+ brelse(bh);
+ return -EFSCORRUPTED;
+ }
+ len = ((char *) root) + (blocksize - csum_size) - (char *) de;
+
+ /* Allocate new block for the 0th block's dirents */
+ bh2 = ext4_append(handle, dir, &block);
+ if (IS_ERR(bh2)) {
+ brelse(bh);
+ return PTR_ERR(bh2);
+ }
+ ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
+ data1 = bh2->b_data;
+
+ memcpy (data1, de, len);
+ de = (struct ext4_dir_entry_2 *) data1;
+ top = data1 + len;
+ while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
+ de = de2;
+ de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
+ (char *) de,
+ blocksize);
+
+ if (csum_size) {
+ t = EXT4_DIRENT_TAIL(data1, blocksize);
+ initialize_dirent_tail(t, blocksize);
+ }
+
+ /* Initialize the root; the dot dirents already exist */
+ de = (struct ext4_dir_entry_2 *) (&root->dotdot);
+ de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
+ blocksize);
+ memset (&root->info, 0, sizeof(root->info));
+ root->info.info_length = sizeof(root->info);
+ root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
+ entries = root->entries;
+ dx_set_block(entries, 1);
+ dx_set_count(entries, 1);
+ dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info)));
+
+ /* Initialize as for dx_probe */
+ fname->hinfo.hash_version = root->info.hash_version;
+ if (fname->hinfo.hash_version <= DX_HASH_TEA)
+ fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
+ fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
+ ext4fs_dirhash(fname_name(fname), fname_len(fname), &fname->hinfo);
+
+ memset(frames, 0, sizeof(frames));
+ frame = frames;
+ frame->entries = entries;
+ frame->at = entries;
+ frame->bh = bh;
+
+ retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
+ if (retval)
+ goto out_frames;
+ retval = ext4_handle_dirty_dirent_node(handle, dir, bh2);
+ if (retval)
+ goto out_frames;
+
+ de = do_split(handle,dir, &bh2, frame, &fname->hinfo);
+ if (IS_ERR(de)) {
+ retval = PTR_ERR(de);
+ goto out_frames;
+ }
+
+ retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2);
+out_frames:
+ /*
+ * Even if the block split failed, we have to properly write
+ * out all the changes we did so far. Otherwise we can end up
+ * with corrupted filesystem.
+ */
+ if (retval)
+ ext4_mark_inode_dirty(handle, dir);
+ dx_release(frames);
+ brelse(bh2);
+ return retval;
+}
+
+/*
+ * ext4_add_entry()
+ *
+ * adds a file entry to the specified directory, using the same
+ * semantics as ext4_find_entry(). It returns NULL if it failed.
+ *
+ * NOTE!! The inode part of 'de' is left at 0 - which means you
+ * may not sleep between calling this and putting something into
+ * the entry, as someone else might have used it while you slept.
+ */
+static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
+ struct inode *inode)
+{
+ struct inode *dir = d_inode(dentry->d_parent);
+ struct buffer_head *bh = NULL;
+ struct ext4_dir_entry_2 *de;
+ struct ext4_dir_entry_tail *t;
+ struct super_block *sb;
+ struct ext4_filename fname;
+ int retval;
+ int dx_fallback=0;
+ unsigned blocksize;
+ ext4_lblk_t block, blocks;
+ int csum_size = 0;
+
+ if (ext4_has_metadata_csum(inode->i_sb))
+ csum_size = sizeof(struct ext4_dir_entry_tail);
+
+ sb = dir->i_sb;
+ blocksize = sb->s_blocksize;
+ if (!dentry->d_name.len)
+ return -EINVAL;
+
+ retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname);
+ if (retval)
+ return retval;
+
+ if (ext4_has_inline_data(dir)) {
+ retval = ext4_try_add_inline_entry(handle, &fname, dir, inode);
+ if (retval < 0)
+ goto out;
+ if (retval == 1) {
+ retval = 0;
+ goto out;
+ }
+ }
+
+ if (is_dx(dir)) {
+ retval = ext4_dx_add_entry(handle, &fname, dir, inode);
+ if (!retval || (retval != ERR_BAD_DX_DIR))
+ goto out;
+ ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
+ dx_fallback++;
+ ext4_mark_inode_dirty(handle, dir);
+ }
+ blocks = dir->i_size >> sb->s_blocksize_bits;
+ for (block = 0; block < blocks; block++) {
+ bh = ext4_read_dirblock(dir, block, DIRENT);
+ if (IS_ERR(bh)) {
+ retval = PTR_ERR(bh);
+ bh = NULL;
+ goto out;
+ }
+ retval = add_dirent_to_buf(handle, &fname, dir, inode,
+ NULL, bh);
+ if (retval != -ENOSPC)
+ goto out;
+
+ if (blocks == 1 && !dx_fallback &&
+ ext4_has_feature_dir_index(sb)) {
+ retval = make_indexed_dir(handle, &fname, dir,
+ inode, bh);
+ bh = NULL; /* make_indexed_dir releases bh */
+ goto out;
+ }
+ brelse(bh);
+ }
+ bh = ext4_append(handle, dir, &block);
+ if (IS_ERR(bh)) {
+ retval = PTR_ERR(bh);
+ bh = NULL;
+ goto out;
+ }
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ de->inode = 0;
+ de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
+
+ if (csum_size) {
+ t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
+ initialize_dirent_tail(t, blocksize);
+ }
+
+ retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh);
+out:
+ ext4_fname_free_filename(&fname);
+ brelse(bh);
+ if (retval == 0)
+ ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);
+ return retval;
+}
+
+/*
+ * Returns 0 for success, or a negative error value
+ */
+static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
+ struct inode *dir, struct inode *inode)
+{
+ struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
+ struct dx_entry *entries, *at;
+ struct buffer_head *bh;
+ struct super_block *sb = dir->i_sb;
+ struct ext4_dir_entry_2 *de;
+ int restart;
+ int err;
+
+again:
+ restart = 0;
+ frame = dx_probe(fname, dir, NULL, frames);
+ if (IS_ERR(frame))
+ return PTR_ERR(frame);
+ entries = frame->entries;
+ at = frame->at;
+ bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT);
+ if (IS_ERR(bh)) {
+ err = PTR_ERR(bh);
+ bh = NULL;
+ goto cleanup;
+ }
+
+ BUFFER_TRACE(bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, bh);
+ if (err)
+ goto journal_error;
+
+ err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh);
+ if (err != -ENOSPC)
+ goto cleanup;
+
+ err = 0;
+ /* Block full, should compress but for now just split */
+ dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
+ dx_get_count(entries), dx_get_limit(entries)));
+ /* Need to split index? */
+ if (dx_get_count(entries) == dx_get_limit(entries)) {
+ ext4_lblk_t newblock;
+ int levels = frame - frames + 1;
+ unsigned int icount;
+ int add_level = 1;
+ struct dx_entry *entries2;
+ struct dx_node *node2;
+ struct buffer_head *bh2;
+
+ while (frame > frames) {
+ if (dx_get_count((frame - 1)->entries) <
+ dx_get_limit((frame - 1)->entries)) {
+ add_level = 0;
+ break;
+ }
+ frame--; /* split higher index block */
+ at = frame->at;
+ entries = frame->entries;
+ restart = 1;
+ }
+ if (add_level && levels == ext4_dir_htree_level(sb)) {
+ ext4_warning(sb, "Directory (ino: %lu) index full, "
+ "reach max htree level :%d",
+ dir->i_ino, levels);
+ if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) {
+ ext4_warning(sb, "Large directory feature is "
+ "not enabled on this "
+ "filesystem");
+ }
+ err = -ENOSPC;
+ goto cleanup;
+ }
+ icount = dx_get_count(entries);
+ bh2 = ext4_append(handle, dir, &newblock);
+ if (IS_ERR(bh2)) {
+ err = PTR_ERR(bh2);
+ goto cleanup;
+ }
+ node2 = (struct dx_node *)(bh2->b_data);
+ entries2 = node2->entries;
+ memset(&node2->fake, 0, sizeof(struct fake_dirent));
+ node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
+ sb->s_blocksize);
+ BUFFER_TRACE(frame->bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, frame->bh);
+ if (err)
+ goto journal_error;
+ if (!add_level) {
+ unsigned icount1 = icount/2, icount2 = icount - icount1;
+ unsigned hash2 = dx_get_hash(entries + icount1);
+ dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",
+ icount1, icount2));
+
+ BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
+ err = ext4_journal_get_write_access(handle,
+ (frame - 1)->bh);
+ if (err)
+ goto journal_error;
+
+ memcpy((char *) entries2, (char *) (entries + icount1),
+ icount2 * sizeof(struct dx_entry));
+ dx_set_count(entries, icount1);
+ dx_set_count(entries2, icount2);
+ dx_set_limit(entries2, dx_node_limit(dir));
+
+ /* Which index block gets the new entry? */
+ if (at - entries >= icount1) {
+ frame->at = at = at - entries - icount1 + entries2;
+ frame->entries = entries = entries2;
+ swap(frame->bh, bh2);
+ }
+ dx_insert_block((frame - 1), hash2, newblock);
+ dxtrace(dx_show_index("node", frame->entries));
+ dxtrace(dx_show_index("node",
+ ((struct dx_node *) bh2->b_data)->entries));
+ err = ext4_handle_dirty_dx_node(handle, dir, bh2);
+ if (err)
+ goto journal_error;
+ brelse (bh2);
+ err = ext4_handle_dirty_dx_node(handle, dir,
+ (frame - 1)->bh);
+ if (err)
+ goto journal_error;
+ if (restart) {
+ err = ext4_handle_dirty_dx_node(handle, dir,
+ frame->bh);
+ goto journal_error;
+ }
+ } else {
+ struct dx_root *dxroot;
+ memcpy((char *) entries2, (char *) entries,
+ icount * sizeof(struct dx_entry));
+ dx_set_limit(entries2, dx_node_limit(dir));
+
+ /* Set up root */
+ dx_set_count(entries, 1);
+ dx_set_block(entries + 0, newblock);
+ dxroot = (struct dx_root *)frames[0].bh->b_data;
+ dxroot->info.indirect_levels += 1;
+ dxtrace(printk(KERN_DEBUG
+ "Creating %d level index...\n",
+ info->indirect_levels));
+ err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
+ if (err)
+ goto journal_error;
+ err = ext4_handle_dirty_dx_node(handle, dir, bh2);
+ brelse(bh2);
+ restart = 1;
+ goto journal_error;
+ }
+ }
+ de = do_split(handle, dir, &bh, frame, &fname->hinfo);
+ if (IS_ERR(de)) {
+ err = PTR_ERR(de);
+ goto cleanup;
+ }
+ err = add_dirent_to_buf(handle, fname, dir, inode, de, bh);
+ goto cleanup;
+
+journal_error:
+ ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */
+cleanup:
+ brelse(bh);
+ dx_release(frames);
+ /* @restart is true means htree-path has been changed, we need to
+ * repeat dx_probe() to find out valid htree-path
+ */
+ if (restart && err == 0)
+ goto again;
+ return err;
+}
+
+/*
+ * ext4_generic_delete_entry deletes a directory entry by merging it
+ * with the previous entry
+ */
+int ext4_generic_delete_entry(handle_t *handle,
+ struct inode *dir,
+ struct ext4_dir_entry_2 *de_del,
+ struct buffer_head *bh,
+ void *entry_buf,
+ int buf_size,
+ int csum_size)
+{
+ struct ext4_dir_entry_2 *de, *pde;
+ unsigned int blocksize = dir->i_sb->s_blocksize;
+ int i;
+
+ i = 0;
+ pde = NULL;
+ de = (struct ext4_dir_entry_2 *)entry_buf;
+ while (i < buf_size - csum_size) {
+ if (ext4_check_dir_entry(dir, NULL, de, bh,
+ bh->b_data, bh->b_size, i))
+ return -EFSCORRUPTED;
+ if (de == de_del) {
+ if (pde)
+ pde->rec_len = ext4_rec_len_to_disk(
+ ext4_rec_len_from_disk(pde->rec_len,
+ blocksize) +
+ ext4_rec_len_from_disk(de->rec_len,
+ blocksize),
+ blocksize);
+ else
+ de->inode = 0;
+ inode_inc_iversion(dir);
+ return 0;
+ }
+ i += ext4_rec_len_from_disk(de->rec_len, blocksize);
+ pde = de;
+ de = ext4_next_entry(de, blocksize);
+ }
+ return -ENOENT;
+}
+
+static int ext4_delete_entry(handle_t *handle,
+ struct inode *dir,
+ struct ext4_dir_entry_2 *de_del,
+ struct buffer_head *bh)
+{
+ int err, csum_size = 0;
+
+ if (ext4_has_inline_data(dir)) {
+ int has_inline_data = 1;
+ err = ext4_delete_inline_entry(handle, dir, de_del, bh,
+ &has_inline_data);
+ if (has_inline_data)
+ return err;
+ }
+
+ if (ext4_has_metadata_csum(dir->i_sb))
+ csum_size = sizeof(struct ext4_dir_entry_tail);
+
+ BUFFER_TRACE(bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, bh);
+ if (unlikely(err))
+ goto out;
+
+ err = ext4_generic_delete_entry(handle, dir, de_del,
+ bh, bh->b_data,
+ dir->i_sb->s_blocksize, csum_size);
+ if (err)
+ goto out;
+
+ BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_dirent_node(handle, dir, bh);
+ if (unlikely(err))
+ goto out;
+
+ return 0;
+out:
+ if (err != -ENOENT)
+ ext4_std_error(dir->i_sb, err);
+ return err;
+}
+
+/*
+ * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2
+ * since this indicates that nlinks count was previously 1 to avoid overflowing
+ * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean
+ * that subdirectory link counts are not being maintained accurately.
+ *
+ * The caller has already checked for i_nlink overflow in case the DIR_LINK
+ * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy
+ * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set
+ * on regular files) and to avoid creating huge/slow non-HTREE directories.
+ */
+static void ext4_inc_count(handle_t *handle, struct inode *inode)
+{
+ inc_nlink(inode);
+ if (is_dx(inode) &&
+ (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2))
+ set_nlink(inode, 1);
+}
+
+/*
+ * If a directory had nlink == 1, then we should let it be 1. This indicates
+ * directory has >EXT4_LINK_MAX subdirs.
+ */
+static void ext4_dec_count(handle_t *handle, struct inode *inode)
+{
+ if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
+ drop_nlink(inode);
+}
+
+
+static int ext4_add_nondir(handle_t *handle,
+ struct dentry *dentry, struct inode *inode)
+{
+ int err = ext4_add_entry(handle, dentry, inode);
+ if (!err) {
+ ext4_mark_inode_dirty(handle, inode);
+ d_instantiate_new(dentry, inode);
+ return 0;
+ }
+ drop_nlink(inode);
+ unlock_new_inode(inode);
+ iput(inode);
+ return err;
+}
+
+/*
+ * By the time this is called, we already have created
+ * the directory cache entry for the new file, but it
+ * is so far negative - it has no inode.
+ *
+ * If the create succeeds, we fill in the inode information
+ * with d_instantiate().
+ */
+static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode,
+ bool excl)
+{
+ handle_t *handle;
+ struct inode *inode;
+ int err, credits, retries = 0;
+
+ err = dquot_initialize(dir);
+ if (err)
+ return err;
+
+ credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
+retry:
+ inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
+ NULL, EXT4_HT_DIR, credits);
+ handle = ext4_journal_current_handle();
+ err = PTR_ERR(inode);
+ if (!IS_ERR(inode)) {
+ inode->i_op = &ext4_file_inode_operations;
+ inode->i_fop = &ext4_file_operations;
+ ext4_set_aops(inode);
+ err = ext4_add_nondir(handle, dentry, inode);
+ if (!err && IS_DIRSYNC(dir))
+ ext4_handle_sync(handle);
+ }
+ if (handle)
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+}
+
+static int ext4_mknod(struct inode *dir, struct dentry *dentry,
+ umode_t mode, dev_t rdev)
+{
+ handle_t *handle;
+ struct inode *inode;
+ int err, credits, retries = 0;
+
+ err = dquot_initialize(dir);
+ if (err)
+ return err;
+
+ credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
+retry:
+ inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
+ NULL, EXT4_HT_DIR, credits);
+ handle = ext4_journal_current_handle();
+ err = PTR_ERR(inode);
+ if (!IS_ERR(inode)) {
+ init_special_inode(inode, inode->i_mode, rdev);
+ inode->i_op = &ext4_special_inode_operations;
+ err = ext4_add_nondir(handle, dentry, inode);
+ if (!err && IS_DIRSYNC(dir))
+ ext4_handle_sync(handle);
+ }
+ if (handle)
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+}
+
+static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+ handle_t *handle;
+ struct inode *inode;
+ int err, retries = 0;
+
+ err = dquot_initialize(dir);
+ if (err)
+ return err;
+
+retry:
+ inode = ext4_new_inode_start_handle(dir, mode,
+ NULL, 0, NULL,
+ EXT4_HT_DIR,
+ EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
+ 4 + EXT4_XATTR_TRANS_BLOCKS);
+ handle = ext4_journal_current_handle();
+ err = PTR_ERR(inode);
+ if (!IS_ERR(inode)) {
+ inode->i_op = &ext4_file_inode_operations;
+ inode->i_fop = &ext4_file_operations;
+ ext4_set_aops(inode);
+ d_tmpfile(dentry, inode);
+ err = ext4_orphan_add(handle, inode);
+ if (err)
+ goto err_unlock_inode;
+ mark_inode_dirty(inode);
+ unlock_new_inode(inode);
+ }
+ if (handle)
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+err_unlock_inode:
+ ext4_journal_stop(handle);
+ unlock_new_inode(inode);
+ return err;
+}
+
+struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
+ struct ext4_dir_entry_2 *de,
+ int blocksize, int csum_size,
+ unsigned int parent_ino, int dotdot_real_len)
+{
+ de->inode = cpu_to_le32(inode->i_ino);
+ de->name_len = 1;
+ de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
+ blocksize);
+ strcpy(de->name, ".");
+ ext4_set_de_type(inode->i_sb, de, S_IFDIR);
+
+ de = ext4_next_entry(de, blocksize);
+ de->inode = cpu_to_le32(parent_ino);
+ de->name_len = 2;
+ if (!dotdot_real_len)
+ de->rec_len = ext4_rec_len_to_disk(blocksize -
+ (csum_size + EXT4_DIR_REC_LEN(1)),
+ blocksize);
+ else
+ de->rec_len = ext4_rec_len_to_disk(
+ EXT4_DIR_REC_LEN(de->name_len), blocksize);
+ strcpy(de->name, "..");
+ ext4_set_de_type(inode->i_sb, de, S_IFDIR);
+
+ return ext4_next_entry(de, blocksize);
+}
+
+static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
+ struct inode *inode)
+{
+ struct buffer_head *dir_block = NULL;
+ struct ext4_dir_entry_2 *de;
+ struct ext4_dir_entry_tail *t;
+ ext4_lblk_t block = 0;
+ unsigned int blocksize = dir->i_sb->s_blocksize;
+ int csum_size = 0;
+ int err;
+
+ if (ext4_has_metadata_csum(dir->i_sb))
+ csum_size = sizeof(struct ext4_dir_entry_tail);
+
+ if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
+ err = ext4_try_create_inline_dir(handle, dir, inode);
+ if (err < 0 && err != -ENOSPC)
+ goto out;
+ if (!err)
+ goto out;
+ }
+
+ inode->i_size = 0;
+ dir_block = ext4_append(handle, inode, &block);
+ if (IS_ERR(dir_block))
+ return PTR_ERR(dir_block);
+ de = (struct ext4_dir_entry_2 *)dir_block->b_data;
+ ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
+ set_nlink(inode, 2);
+ if (csum_size) {
+ t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
+ initialize_dirent_tail(t, blocksize);
+ }
+
+ BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
+ if (err)
+ goto out;
+ set_buffer_verified(dir_block);
+out:
+ brelse(dir_block);
+ return err;
+}
+
+static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+ handle_t *handle;
+ struct inode *inode;
+ int err, credits, retries = 0;
+
+ if (EXT4_DIR_LINK_MAX(dir))
+ return -EMLINK;
+
+ err = dquot_initialize(dir);
+ if (err)
+ return err;
+
+ credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
+retry:
+ inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode,
+ &dentry->d_name,
+ 0, NULL, EXT4_HT_DIR, credits);
+ handle = ext4_journal_current_handle();
+ err = PTR_ERR(inode);
+ if (IS_ERR(inode))
+ goto out_stop;
+
+ inode->i_op = &ext4_dir_inode_operations;
+ inode->i_fop = &ext4_dir_operations;
+ err = ext4_init_new_dir(handle, dir, inode);
+ if (err)
+ goto out_clear_inode;
+ err = ext4_mark_inode_dirty(handle, inode);
+ if (!err)
+ err = ext4_add_entry(handle, dentry, inode);
+ if (err) {
+out_clear_inode:
+ clear_nlink(inode);
+ unlock_new_inode(inode);
+ ext4_mark_inode_dirty(handle, inode);
+ iput(inode);
+ goto out_stop;
+ }
+ ext4_inc_count(handle, dir);
+ ext4_update_dx_flag(dir);
+ err = ext4_mark_inode_dirty(handle, dir);
+ if (err)
+ goto out_clear_inode;
+ d_instantiate_new(dentry, inode);
+ if (IS_DIRSYNC(dir))
+ ext4_handle_sync(handle);
+
+out_stop:
+ if (handle)
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+}
+
+/*
+ * routine to check that the specified directory is empty (for rmdir)
+ */
+bool ext4_empty_dir(struct inode *inode)
+{
+ unsigned int offset;
+ struct buffer_head *bh;
+ struct ext4_dir_entry_2 *de, *de1;
+ struct super_block *sb;
+
+ if (ext4_has_inline_data(inode)) {
+ int has_inline_data = 1;
+ int ret;
+
+ ret = empty_inline_dir(inode, &has_inline_data);
+ if (has_inline_data)
+ return ret;
+ }
+
+ sb = inode->i_sb;
+ if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) {
+ EXT4_ERROR_INODE(inode, "invalid size");
+ return true;
+ }
+ bh = ext4_read_dirblock(inode, 0, EITHER);
+ if (IS_ERR(bh))
+ return true;
+
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ de1 = ext4_next_entry(de, sb->s_blocksize);
+ if (le32_to_cpu(de->inode) != inode->i_ino ||
+ le32_to_cpu(de1->inode) == 0 ||
+ strcmp(".", de->name) || strcmp("..", de1->name)) {
+ ext4_warning_inode(inode, "directory missing '.' and/or '..'");
+ brelse(bh);
+ return true;
+ }
+ offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
+ ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
+ de = ext4_next_entry(de1, sb->s_blocksize);
+ while (offset < inode->i_size) {
+ if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
+ unsigned int lblock;
+ brelse(bh);
+ lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
+ bh = ext4_read_dirblock(inode, lblock, EITHER);
+ if (IS_ERR(bh))
+ return true;
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ }
+ if (ext4_check_dir_entry(inode, NULL, de, bh,
+ bh->b_data, bh->b_size, offset)) {
+ de = (struct ext4_dir_entry_2 *)(bh->b_data +
+ sb->s_blocksize);
+ offset = (offset | (sb->s_blocksize - 1)) + 1;
+ continue;
+ }
+ if (le32_to_cpu(de->inode)) {
+ brelse(bh);
+ return false;
+ }
+ offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
+ de = ext4_next_entry(de, sb->s_blocksize);
+ }
+ brelse(bh);
+ return true;
+}
+
+/*
+ * ext4_orphan_add() links an unlinked or truncated inode into a list of
+ * such inodes, starting at the superblock, in case we crash before the
+ * file is closed/deleted, or in case the inode truncate spans multiple
+ * transactions and the last transaction is not recovered after a crash.
+ *
+ * At filesystem recovery time, we walk this list deleting unlinked
+ * inodes and truncating linked inodes in ext4_orphan_cleanup().
+ *
+ * Orphan list manipulation functions must be called under i_mutex unless
+ * we are just creating the inode or deleting it.
+ */
+int ext4_orphan_add(handle_t *handle, struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_iloc iloc;
+ int err = 0, rc;
+ bool dirty = false;
+
+ if (!sbi->s_journal || is_bad_inode(inode))
+ return 0;
+
+ WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
+ !inode_is_locked(inode));
+ /*
+ * Exit early if inode already is on orphan list. This is a big speedup
+ * since we don't have to contend on the global s_orphan_lock.
+ */
+ if (!list_empty(&EXT4_I(inode)->i_orphan))
+ return 0;
+
+ /*
+ * Orphan handling is only valid for files with data blocks
+ * being truncated, or files being unlinked. Note that we either
+ * hold i_mutex, or the inode can not be referenced from outside,
+ * so i_nlink should not be bumped due to race
+ */
+ J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+ S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
+
+ BUFFER_TRACE(sbi->s_sbh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, sbi->s_sbh);
+ if (err)
+ goto out;
+
+ err = ext4_reserve_inode_write(handle, inode, &iloc);
+ if (err)
+ goto out;
+
+ mutex_lock(&sbi->s_orphan_lock);
+ /*
+ * Due to previous errors inode may be already a part of on-disk
+ * orphan list. If so skip on-disk list modification.
+ */
+ if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) >
+ (le32_to_cpu(sbi->s_es->s_inodes_count))) {
+ /* Insert this inode at the head of the on-disk orphan list */
+ NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan);
+ sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
+ dirty = true;
+ }
+ list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan);
+ mutex_unlock(&sbi->s_orphan_lock);
+
+ if (dirty) {
+ err = ext4_handle_dirty_super(handle, sb);
+ rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
+ if (!err)
+ err = rc;
+ if (err) {
+ /*
+ * We have to remove inode from in-memory list if
+ * addition to on disk orphan list failed. Stray orphan
+ * list entries can cause panics at unmount time.
+ */
+ mutex_lock(&sbi->s_orphan_lock);
+ list_del_init(&EXT4_I(inode)->i_orphan);
+ mutex_unlock(&sbi->s_orphan_lock);
+ }
+ } else
+ brelse(iloc.bh);
+
+ jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
+ jbd_debug(4, "orphan inode %lu will point to %d\n",
+ inode->i_ino, NEXT_ORPHAN(inode));
+out:
+ ext4_std_error(sb, err);
+ return err;
+}
+
+/*
+ * ext4_orphan_del() removes an unlinked or truncated inode from the list
+ * of such inodes stored on disk, because it is finally being cleaned up.
+ */
+int ext4_orphan_del(handle_t *handle, struct inode *inode)
+{
+ struct list_head *prev;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ __u32 ino_next;
+ struct ext4_iloc iloc;
+ int err = 0;
+
+ if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS))
+ return 0;
+
+ WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
+ !inode_is_locked(inode));
+ /* Do this quick check before taking global s_orphan_lock. */
+ if (list_empty(&ei->i_orphan))
+ return 0;
+
+ if (handle) {
+ /* Grab inode buffer early before taking global s_orphan_lock */
+ err = ext4_reserve_inode_write(handle, inode, &iloc);
+ }
+
+ mutex_lock(&sbi->s_orphan_lock);
+ jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
+
+ prev = ei->i_orphan.prev;
+ list_del_init(&ei->i_orphan);
+
+ /* If we're on an error path, we may not have a valid
+ * transaction handle with which to update the orphan list on
+ * disk, but we still need to remove the inode from the linked
+ * list in memory. */
+ if (!handle || err) {
+ mutex_unlock(&sbi->s_orphan_lock);
+ goto out_err;
+ }
+
+ ino_next = NEXT_ORPHAN(inode);
+ if (prev == &sbi->s_orphan) {
+ jbd_debug(4, "superblock will point to %u\n", ino_next);
+ BUFFER_TRACE(sbi->s_sbh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, sbi->s_sbh);
+ if (err) {
+ mutex_unlock(&sbi->s_orphan_lock);
+ goto out_brelse;
+ }
+ sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
+ mutex_unlock(&sbi->s_orphan_lock);
+ err = ext4_handle_dirty_super(handle, inode->i_sb);
+ } else {
+ struct ext4_iloc iloc2;
+ struct inode *i_prev =
+ &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
+
+ jbd_debug(4, "orphan inode %lu will point to %u\n",
+ i_prev->i_ino, ino_next);
+ err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
+ if (err) {
+ mutex_unlock(&sbi->s_orphan_lock);
+ goto out_brelse;
+ }
+ NEXT_ORPHAN(i_prev) = ino_next;
+ err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
+ mutex_unlock(&sbi->s_orphan_lock);
+ }
+ if (err)
+ goto out_brelse;
+ NEXT_ORPHAN(inode) = 0;
+ err = ext4_mark_iloc_dirty(handle, inode, &iloc);
+out_err:
+ ext4_std_error(inode->i_sb, err);
+ return err;
+
+out_brelse:
+ brelse(iloc.bh);
+ goto out_err;
+}
+
+static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ int retval;
+ struct inode *inode;
+ struct buffer_head *bh;
+ struct ext4_dir_entry_2 *de;
+ handle_t *handle = NULL;
+
+ if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
+ return -EIO;
+
+ /* Initialize quotas before so that eventual writes go in
+ * separate transaction */
+ retval = dquot_initialize(dir);
+ if (retval)
+ return retval;
+ retval = dquot_initialize(d_inode(dentry));
+ if (retval)
+ return retval;
+
+ retval = -ENOENT;
+ bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
+ if (IS_ERR(bh))
+ return PTR_ERR(bh);
+ if (!bh)
+ goto end_rmdir;
+
+ inode = d_inode(dentry);
+
+ retval = -EFSCORRUPTED;
+ if (le32_to_cpu(de->inode) != inode->i_ino)
+ goto end_rmdir;
+
+ retval = -ENOTEMPTY;
+ if (!ext4_empty_dir(inode))
+ goto end_rmdir;
+
+ handle = ext4_journal_start(dir, EXT4_HT_DIR,
+ EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
+ if (IS_ERR(handle)) {
+ retval = PTR_ERR(handle);
+ handle = NULL;
+ goto end_rmdir;
+ }
+
+ if (IS_DIRSYNC(dir))
+ ext4_handle_sync(handle);
+
+ retval = ext4_delete_entry(handle, dir, de, bh);
+ if (retval)
+ goto end_rmdir;
+ if (!EXT4_DIR_LINK_EMPTY(inode))
+ ext4_warning_inode(inode,
+ "empty directory '%.*s' has too many links (%u)",
+ dentry->d_name.len, dentry->d_name.name,
+ inode->i_nlink);
+ inode_inc_iversion(inode);
+ clear_nlink(inode);
+ /* There's no need to set i_disksize: the fact that i_nlink is
+ * zero will ensure that the right thing happens during any
+ * recovery. */
+ inode->i_size = 0;
+ ext4_orphan_add(handle, inode);
+ inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode);
+ ext4_mark_inode_dirty(handle, inode);
+ ext4_dec_count(handle, dir);
+ ext4_update_dx_flag(dir);
+ ext4_mark_inode_dirty(handle, dir);
+
+end_rmdir:
+ brelse(bh);
+ if (handle)
+ ext4_journal_stop(handle);
+ return retval;
+}
+
+static int ext4_unlink(struct inode *dir, struct dentry *dentry)
+{
+ int retval;
+ struct inode *inode;
+ struct buffer_head *bh;
+ struct ext4_dir_entry_2 *de;
+ handle_t *handle = NULL;
+
+ if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
+ return -EIO;
+
+ trace_ext4_unlink_enter(dir, dentry);
+ /* Initialize quotas before so that eventual writes go
+ * in separate transaction */
+ retval = dquot_initialize(dir);
+ if (retval)
+ return retval;
+ retval = dquot_initialize(d_inode(dentry));
+ if (retval)
+ return retval;
+
+ retval = -ENOENT;
+ bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
+ if (IS_ERR(bh))
+ return PTR_ERR(bh);
+ if (!bh)
+ goto end_unlink;
+
+ inode = d_inode(dentry);
+
+ retval = -EFSCORRUPTED;
+ if (le32_to_cpu(de->inode) != inode->i_ino)
+ goto end_unlink;
+
+ handle = ext4_journal_start(dir, EXT4_HT_DIR,
+ EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
+ if (IS_ERR(handle)) {
+ retval = PTR_ERR(handle);
+ handle = NULL;
+ goto end_unlink;
+ }
+
+ if (IS_DIRSYNC(dir))
+ ext4_handle_sync(handle);
+
+ if (inode->i_nlink == 0) {
+ ext4_warning_inode(inode, "Deleting file '%.*s' with no links",
+ dentry->d_name.len, dentry->d_name.name);
+ set_nlink(inode, 1);
+ }
+ retval = ext4_delete_entry(handle, dir, de, bh);
+ if (retval)
+ goto end_unlink;
+ dir->i_ctime = dir->i_mtime = current_time(dir);
+ ext4_update_dx_flag(dir);
+ ext4_mark_inode_dirty(handle, dir);
+ drop_nlink(inode);
+ if (!inode->i_nlink)
+ ext4_orphan_add(handle, inode);
+ inode->i_ctime = current_time(inode);
+ ext4_mark_inode_dirty(handle, inode);
+
+end_unlink:
+ brelse(bh);
+ if (handle)
+ ext4_journal_stop(handle);
+ trace_ext4_unlink_exit(dentry, retval);
+ return retval;
+}
+
+static int ext4_symlink(struct inode *dir,
+ struct dentry *dentry, const char *symname)
+{
+ handle_t *handle;
+ struct inode *inode;
+ int err, len = strlen(symname);
+ int credits;
+ struct fscrypt_str disk_link;
+
+ if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
+ return -EIO;
+
+ err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize,
+ &disk_link);
+ if (err)
+ return err;
+
+ err = dquot_initialize(dir);
+ if (err)
+ return err;
+
+ if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
+ /*
+ * For non-fast symlinks, we just allocate inode and put it on
+ * orphan list in the first transaction => we need bitmap,
+ * group descriptor, sb, inode block, quota blocks, and
+ * possibly selinux xattr blocks.
+ */
+ credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
+ EXT4_XATTR_TRANS_BLOCKS;
+ } else {
+ /*
+ * Fast symlink. We have to add entry to directory
+ * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS),
+ * allocate new inode (bitmap, group descriptor, inode block,
+ * quota blocks, sb is already counted in previous macros).
+ */
+ credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
+ }
+
+ inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO,
+ &dentry->d_name, 0, NULL,
+ EXT4_HT_DIR, credits);
+ handle = ext4_journal_current_handle();
+ if (IS_ERR(inode)) {
+ if (handle)
+ ext4_journal_stop(handle);
+ return PTR_ERR(inode);
+ }
+
+ if (IS_ENCRYPTED(inode)) {
+ err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
+ if (err)
+ goto err_drop_inode;
+ inode->i_op = &ext4_encrypted_symlink_inode_operations;
+ }
+
+ if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
+ if (!IS_ENCRYPTED(inode))
+ inode->i_op = &ext4_symlink_inode_operations;
+ inode_nohighmem(inode);
+ ext4_set_aops(inode);
+ /*
+ * We cannot call page_symlink() with transaction started
+ * because it calls into ext4_write_begin() which can wait
+ * for transaction commit if we are running out of space
+ * and thus we deadlock. So we have to stop transaction now
+ * and restart it when symlink contents is written.
+ *
+ * To keep fs consistent in case of crash, we have to put inode
+ * to orphan list in the mean time.
+ */
+ drop_nlink(inode);
+ err = ext4_orphan_add(handle, inode);
+ ext4_journal_stop(handle);
+ handle = NULL;
+ if (err)
+ goto err_drop_inode;
+ err = __page_symlink(inode, disk_link.name, disk_link.len, 1);
+ if (err)
+ goto err_drop_inode;
+ /*
+ * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS
+ * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
+ */
+ handle = ext4_journal_start(dir, EXT4_HT_DIR,
+ EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1);
+ if (IS_ERR(handle)) {
+ err = PTR_ERR(handle);
+ handle = NULL;
+ goto err_drop_inode;
+ }
+ set_nlink(inode, 1);
+ err = ext4_orphan_del(handle, inode);
+ if (err)
+ goto err_drop_inode;
+ } else {
+ /* clear the extent format for fast symlink */
+ ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
+ if (!IS_ENCRYPTED(inode)) {
+ inode->i_op = &ext4_fast_symlink_inode_operations;
+ inode->i_link = (char *)&EXT4_I(inode)->i_data;
+ }
+ memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name,
+ disk_link.len);
+ inode->i_size = disk_link.len - 1;
+ }
+ EXT4_I(inode)->i_disksize = inode->i_size;
+ err = ext4_add_nondir(handle, dentry, inode);
+ if (!err && IS_DIRSYNC(dir))
+ ext4_handle_sync(handle);
+
+ if (handle)
+ ext4_journal_stop(handle);
+ goto out_free_encrypted_link;
+
+err_drop_inode:
+ if (handle)
+ ext4_journal_stop(handle);
+ clear_nlink(inode);
+ unlock_new_inode(inode);
+ iput(inode);
+out_free_encrypted_link:
+ if (disk_link.name != (unsigned char *)symname)
+ kfree(disk_link.name);
+ return err;
+}
+
+static int ext4_link(struct dentry *old_dentry,
+ struct inode *dir, struct dentry *dentry)
+{
+ handle_t *handle;
+ struct inode *inode = d_inode(old_dentry);
+ int err, retries = 0;
+
+ if (inode->i_nlink >= EXT4_LINK_MAX)
+ return -EMLINK;
+
+ err = fscrypt_prepare_link(old_dentry, dir, dentry);
+ if (err)
+ return err;
+
+ if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) &&
+ (!projid_eq(EXT4_I(dir)->i_projid,
+ EXT4_I(old_dentry->d_inode)->i_projid)))
+ return -EXDEV;
+
+ err = dquot_initialize(dir);
+ if (err)
+ return err;
+
+retry:
+ handle = ext4_journal_start(dir, EXT4_HT_DIR,
+ (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(dir))
+ ext4_handle_sync(handle);
+
+ inode->i_ctime = current_time(inode);
+ ext4_inc_count(handle, inode);
+ ihold(inode);
+
+ err = ext4_add_entry(handle, dentry, inode);
+ if (!err) {
+ ext4_mark_inode_dirty(handle, inode);
+ /* this can happen only for tmpfile being
+ * linked the first time
+ */
+ if (inode->i_nlink == 1)
+ ext4_orphan_del(handle, inode);
+ d_instantiate(dentry, inode);
+ } else {
+ drop_nlink(inode);
+ iput(inode);
+ }
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+}
+
+
+/*
+ * Try to find buffer head where contains the parent block.
+ * It should be the inode block if it is inlined or the 1st block
+ * if it is a normal dir.
+ */
+static struct buffer_head *ext4_get_first_dir_block(handle_t *handle,
+ struct inode *inode,
+ int *retval,
+ struct ext4_dir_entry_2 **parent_de,
+ int *inlined)
+{
+ struct buffer_head *bh;
+
+ if (!ext4_has_inline_data(inode)) {
+ bh = ext4_read_dirblock(inode, 0, EITHER);
+ if (IS_ERR(bh)) {
+ *retval = PTR_ERR(bh);
+ return NULL;
+ }
+ *parent_de = ext4_next_entry(
+ (struct ext4_dir_entry_2 *)bh->b_data,
+ inode->i_sb->s_blocksize);
+ return bh;
+ }
+
+ *inlined = 1;
+ return ext4_get_first_inline_block(inode, parent_de, retval);
+}
+
+struct ext4_renament {
+ struct inode *dir;
+ struct dentry *dentry;
+ struct inode *inode;
+ bool is_dir;
+ int dir_nlink_delta;
+
+ /* entry for "dentry" */
+ struct buffer_head *bh;
+ struct ext4_dir_entry_2 *de;
+ int inlined;
+
+ /* entry for ".." in inode if it's a directory */
+ struct buffer_head *dir_bh;
+ struct ext4_dir_entry_2 *parent_de;
+ int dir_inlined;
+};
+
+static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent)
+{
+ int retval;
+
+ ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode,
+ &retval, &ent->parent_de,
+ &ent->dir_inlined);
+ if (!ent->dir_bh)
+ return retval;
+ if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)
+ return -EFSCORRUPTED;
+ BUFFER_TRACE(ent->dir_bh, "get_write_access");
+ return ext4_journal_get_write_access(handle, ent->dir_bh);
+}
+
+static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
+ unsigned dir_ino)
+{
+ int retval;
+
+ ent->parent_de->inode = cpu_to_le32(dir_ino);
+ BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");
+ if (!ent->dir_inlined) {
+ if (is_dx(ent->inode)) {
+ retval = ext4_handle_dirty_dx_node(handle,
+ ent->inode,
+ ent->dir_bh);
+ } else {
+ retval = ext4_handle_dirty_dirent_node(handle,
+ ent->inode,
+ ent->dir_bh);
+ }
+ } else {
+ retval = ext4_mark_inode_dirty(handle, ent->inode);
+ }
+ if (retval) {
+ ext4_std_error(ent->dir->i_sb, retval);
+ return retval;
+ }
+ return 0;
+}
+
+static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
+ unsigned ino, unsigned file_type)
+{
+ int retval;
+
+ BUFFER_TRACE(ent->bh, "get write access");
+ retval = ext4_journal_get_write_access(handle, ent->bh);
+ if (retval)
+ return retval;
+ ent->de->inode = cpu_to_le32(ino);
+ if (ext4_has_feature_filetype(ent->dir->i_sb))
+ ent->de->file_type = file_type;
+ inode_inc_iversion(ent->dir);
+ ent->dir->i_ctime = ent->dir->i_mtime =
+ current_time(ent->dir);
+ ext4_mark_inode_dirty(handle, ent->dir);
+ BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
+ if (!ent->inlined) {
+ retval = ext4_handle_dirty_dirent_node(handle,
+ ent->dir, ent->bh);
+ if (unlikely(retval)) {
+ ext4_std_error(ent->dir->i_sb, retval);
+ return retval;
+ }
+ }
+ brelse(ent->bh);
+ ent->bh = NULL;
+
+ return 0;
+}
+
+static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,
+ const struct qstr *d_name)
+{
+ int retval = -ENOENT;
+ struct buffer_head *bh;
+ struct ext4_dir_entry_2 *de;
+
+ bh = ext4_find_entry(dir, d_name, &de, NULL);
+ if (IS_ERR(bh))
+ return PTR_ERR(bh);
+ if (bh) {
+ retval = ext4_delete_entry(handle, dir, de, bh);
+ brelse(bh);
+ }
+ return retval;
+}
+
+static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent,
+ int force_reread)
+{
+ int retval;
+ /*
+ * ent->de could have moved from under us during htree split, so make
+ * sure that we are deleting the right entry. We might also be pointing
+ * to a stale entry in the unused part of ent->bh so just checking inum
+ * and the name isn't enough.
+ */
+ if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||
+ ent->de->name_len != ent->dentry->d_name.len ||
+ strncmp(ent->de->name, ent->dentry->d_name.name,
+ ent->de->name_len) ||
+ force_reread) {
+ retval = ext4_find_delete_entry(handle, ent->dir,
+ &ent->dentry->d_name);
+ } else {
+ retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh);
+ if (retval == -ENOENT) {
+ retval = ext4_find_delete_entry(handle, ent->dir,
+ &ent->dentry->d_name);
+ }
+ }
+
+ if (retval) {
+ ext4_warning_inode(ent->dir,
+ "Deleting old file: nlink %d, error=%d",
+ ent->dir->i_nlink, retval);
+ }
+}
+
+static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
+{
+ if (ent->dir_nlink_delta) {
+ if (ent->dir_nlink_delta == -1)
+ ext4_dec_count(handle, ent->dir);
+ else
+ ext4_inc_count(handle, ent->dir);
+ ext4_mark_inode_dirty(handle, ent->dir);
+ }
+}
+
+static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent,
+ int credits, handle_t **h)
+{
+ struct inode *wh;
+ handle_t *handle;
+ int retries = 0;
+
+ /*
+ * for inode block, sb block, group summaries,
+ * and inode bitmap
+ */
+ credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) +
+ EXT4_XATTR_TRANS_BLOCKS + 4);
+retry:
+ wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE,
+ &ent->dentry->d_name, 0, NULL,
+ EXT4_HT_DIR, credits);
+
+ handle = ext4_journal_current_handle();
+ if (IS_ERR(wh)) {
+ if (handle)
+ ext4_journal_stop(handle);
+ if (PTR_ERR(wh) == -ENOSPC &&
+ ext4_should_retry_alloc(ent->dir->i_sb, &retries))
+ goto retry;
+ } else {
+ *h = handle;
+ init_special_inode(wh, wh->i_mode, WHITEOUT_DEV);
+ wh->i_op = &ext4_special_inode_operations;
+ }
+ return wh;
+}
+
+/*
+ * Anybody can rename anything with this: the permission checks are left to the
+ * higher-level routines.
+ *
+ * n.b. old_{dentry,inode) refers to the source dentry/inode
+ * while new_{dentry,inode) refers to the destination dentry/inode
+ * This comes from rename(const char *oldpath, const char *newpath)
+ */
+static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
+{
+ handle_t *handle = NULL;
+ struct ext4_renament old = {
+ .dir = old_dir,
+ .dentry = old_dentry,
+ .inode = d_inode(old_dentry),
+ };
+ struct ext4_renament new = {
+ .dir = new_dir,
+ .dentry = new_dentry,
+ .inode = d_inode(new_dentry),
+ };
+ int force_reread;
+ int retval;
+ struct inode *whiteout = NULL;
+ int credits;
+ u8 old_file_type;
+
+ if (new.inode && new.inode->i_nlink == 0) {
+ EXT4_ERROR_INODE(new.inode,
+ "target of rename is already freed");
+ return -EFSCORRUPTED;
+ }
+
+ if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) &&
+ (!projid_eq(EXT4_I(new_dir)->i_projid,
+ EXT4_I(old_dentry->d_inode)->i_projid)))
+ return -EXDEV;
+
+ retval = dquot_initialize(old.dir);
+ if (retval)
+ return retval;
+ retval = dquot_initialize(new.dir);
+ if (retval)
+ return retval;
+
+ /* Initialize quotas before so that eventual writes go
+ * in separate transaction */
+ if (new.inode) {
+ retval = dquot_initialize(new.inode);
+ if (retval)
+ return retval;
+ }
+
+ old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL);
+ if (IS_ERR(old.bh))
+ return PTR_ERR(old.bh);
+ /*
+ * Check for inode number is _not_ due to possible IO errors.
+ * We might rmdir the source, keep it as pwd of some process
+ * and merrily kill the link to whatever was created under the
+ * same name. Goodbye sticky bit ;-<
+ */
+ retval = -ENOENT;
+ if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
+ goto end_rename;
+
+ new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
+ &new.de, &new.inlined);
+ if (IS_ERR(new.bh)) {
+ retval = PTR_ERR(new.bh);
+ new.bh = NULL;
+ goto end_rename;
+ }
+ if (new.bh) {
+ if (!new.inode) {
+ brelse(new.bh);
+ new.bh = NULL;
+ }
+ }
+ if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))
+ ext4_alloc_da_blocks(old.inode);
+
+ credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
+ if (!(flags & RENAME_WHITEOUT)) {
+ handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits);
+ if (IS_ERR(handle)) {
+ retval = PTR_ERR(handle);
+ handle = NULL;
+ goto end_rename;
+ }
+ } else {
+ whiteout = ext4_whiteout_for_rename(&old, credits, &handle);
+ if (IS_ERR(whiteout)) {
+ retval = PTR_ERR(whiteout);
+ whiteout = NULL;
+ goto end_rename;
+ }
+ }
+
+ if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
+ ext4_handle_sync(handle);
+
+ if (S_ISDIR(old.inode->i_mode)) {
+ if (new.inode) {
+ retval = -ENOTEMPTY;
+ if (!ext4_empty_dir(new.inode))
+ goto end_rename;
+ } else {
+ retval = -EMLINK;
+ if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
+ goto end_rename;
+ }
+ retval = ext4_rename_dir_prepare(handle, &old);
+ if (retval)
+ goto end_rename;
+ }
+ /*
+ * If we're renaming a file within an inline_data dir and adding or
+ * setting the new dirent causes a conversion from inline_data to
+ * extents/blockmap, we need to force the dirent delete code to
+ * re-read the directory, or else we end up trying to delete a dirent
+ * from what is now the extent tree root (or a block map).
+ */
+ force_reread = (new.dir->i_ino == old.dir->i_ino &&
+ ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA));
+
+ old_file_type = old.de->file_type;
+ if (whiteout) {
+ /*
+ * Do this before adding a new entry, so the old entry is sure
+ * to be still pointing to the valid old entry.
+ */
+ retval = ext4_setent(handle, &old, whiteout->i_ino,
+ EXT4_FT_CHRDEV);
+ if (retval)
+ goto end_rename;
+ ext4_mark_inode_dirty(handle, whiteout);
+ }
+ if (!new.bh) {
+ retval = ext4_add_entry(handle, new.dentry, old.inode);
+ if (retval)
+ goto end_rename;
+ } else {
+ retval = ext4_setent(handle, &new,
+ old.inode->i_ino, old_file_type);
+ if (retval)
+ goto end_rename;
+ }
+ if (force_reread)
+ force_reread = !ext4_test_inode_flag(new.dir,
+ EXT4_INODE_INLINE_DATA);
+
+ /*
+ * Like most other Unix systems, set the ctime for inodes on a
+ * rename.
+ */
+ old.inode->i_ctime = current_time(old.inode);
+ ext4_mark_inode_dirty(handle, old.inode);
+
+ if (!whiteout) {
+ /*
+ * ok, that's it
+ */
+ ext4_rename_delete(handle, &old, force_reread);
+ }
+
+ if (new.inode) {
+ ext4_dec_count(handle, new.inode);
+ new.inode->i_ctime = current_time(new.inode);
+ }
+ old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir);
+ ext4_update_dx_flag(old.dir);
+ if (old.dir_bh) {
+ retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
+ if (retval)
+ goto end_rename;
+
+ ext4_dec_count(handle, old.dir);
+ if (new.inode) {
+ /* checked ext4_empty_dir above, can't have another
+ * parent, ext4_dec_count() won't work for many-linked
+ * dirs */
+ clear_nlink(new.inode);
+ } else {
+ ext4_inc_count(handle, new.dir);
+ ext4_update_dx_flag(new.dir);
+ ext4_mark_inode_dirty(handle, new.dir);
+ }
+ }
+ ext4_mark_inode_dirty(handle, old.dir);
+ if (new.inode) {
+ ext4_mark_inode_dirty(handle, new.inode);
+ if (!new.inode->i_nlink)
+ ext4_orphan_add(handle, new.inode);
+ }
+ retval = 0;
+
+end_rename:
+ brelse(old.dir_bh);
+ brelse(old.bh);
+ brelse(new.bh);
+ if (whiteout) {
+ if (retval)
+ drop_nlink(whiteout);
+ unlock_new_inode(whiteout);
+ iput(whiteout);
+ }
+ if (handle)
+ ext4_journal_stop(handle);
+ return retval;
+}
+
+static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ handle_t *handle = NULL;
+ struct ext4_renament old = {
+ .dir = old_dir,
+ .dentry = old_dentry,
+ .inode = d_inode(old_dentry),
+ };
+ struct ext4_renament new = {
+ .dir = new_dir,
+ .dentry = new_dentry,
+ .inode = d_inode(new_dentry),
+ };
+ u8 new_file_type;
+ int retval;
+ struct timespec64 ctime;
+
+ if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) &&
+ !projid_eq(EXT4_I(new_dir)->i_projid,
+ EXT4_I(old_dentry->d_inode)->i_projid)) ||
+ (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) &&
+ !projid_eq(EXT4_I(old_dir)->i_projid,
+ EXT4_I(new_dentry->d_inode)->i_projid)))
+ return -EXDEV;
+
+ retval = dquot_initialize(old.dir);
+ if (retval)
+ return retval;
+ retval = dquot_initialize(new.dir);
+ if (retval)
+ return retval;
+
+ old.bh = ext4_find_entry(old.dir, &old.dentry->d_name,
+ &old.de, &old.inlined);
+ if (IS_ERR(old.bh))
+ return PTR_ERR(old.bh);
+ /*
+ * Check for inode number is _not_ due to possible IO errors.
+ * We might rmdir the source, keep it as pwd of some process
+ * and merrily kill the link to whatever was created under the
+ * same name. Goodbye sticky bit ;-<
+ */
+ retval = -ENOENT;
+ if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
+ goto end_rename;
+
+ new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
+ &new.de, &new.inlined);
+ if (IS_ERR(new.bh)) {
+ retval = PTR_ERR(new.bh);
+ new.bh = NULL;
+ goto end_rename;
+ }
+
+ /* RENAME_EXCHANGE case: old *and* new must both exist */
+ if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino)
+ goto end_rename;
+
+ handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
+ (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
+ 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
+ if (IS_ERR(handle)) {
+ retval = PTR_ERR(handle);
+ handle = NULL;
+ goto end_rename;
+ }
+
+ if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
+ ext4_handle_sync(handle);
+
+ if (S_ISDIR(old.inode->i_mode)) {
+ old.is_dir = true;
+ retval = ext4_rename_dir_prepare(handle, &old);
+ if (retval)
+ goto end_rename;
+ }
+ if (S_ISDIR(new.inode->i_mode)) {
+ new.is_dir = true;
+ retval = ext4_rename_dir_prepare(handle, &new);
+ if (retval)
+ goto end_rename;
+ }
+
+ /*
+ * Other than the special case of overwriting a directory, parents'
+ * nlink only needs to be modified if this is a cross directory rename.
+ */
+ if (old.dir != new.dir && old.is_dir != new.is_dir) {
+ old.dir_nlink_delta = old.is_dir ? -1 : 1;
+ new.dir_nlink_delta = -old.dir_nlink_delta;
+ retval = -EMLINK;
+ if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) ||
+ (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir)))
+ goto end_rename;
+ }
+
+ new_file_type = new.de->file_type;
+ retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type);
+ if (retval)
+ goto end_rename;
+
+ retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type);
+ if (retval)
+ goto end_rename;
+
+ /*
+ * Like most other Unix systems, set the ctime for inodes on a
+ * rename.
+ */
+ ctime = current_time(old.inode);
+ old.inode->i_ctime = ctime;
+ new.inode->i_ctime = ctime;
+ ext4_mark_inode_dirty(handle, old.inode);
+ ext4_mark_inode_dirty(handle, new.inode);
+
+ if (old.dir_bh) {
+ retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
+ if (retval)
+ goto end_rename;
+ }
+ if (new.dir_bh) {
+ retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino);
+ if (retval)
+ goto end_rename;
+ }
+ ext4_update_dir_count(handle, &old);
+ ext4_update_dir_count(handle, &new);
+ retval = 0;
+
+end_rename:
+ brelse(old.dir_bh);
+ brelse(new.dir_bh);
+ brelse(old.bh);
+ brelse(new.bh);
+ if (handle)
+ ext4_journal_stop(handle);
+ return retval;
+}
+
+static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
+{
+ int err;
+
+ if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb))))
+ return -EIO;
+
+ if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
+ return -EINVAL;
+
+ err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
+ flags);
+ if (err)
+ return err;
+
+ if (flags & RENAME_EXCHANGE) {
+ return ext4_cross_rename(old_dir, old_dentry,
+ new_dir, new_dentry);
+ }
+
+ return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
+}
+
+/*
+ * directories can handle most operations...
+ */
+const struct inode_operations ext4_dir_inode_operations = {
+ .create = ext4_create,
+ .lookup = ext4_lookup,
+ .link = ext4_link,
+ .unlink = ext4_unlink,
+ .symlink = ext4_symlink,
+ .mkdir = ext4_mkdir,
+ .rmdir = ext4_rmdir,
+ .mknod = ext4_mknod,
+ .tmpfile = ext4_tmpfile,
+ .rename = ext4_rename2,
+ .setattr = ext4_setattr,
+ .getattr = ext4_getattr,
+ .listxattr = ext4_listxattr,
+ .get_acl = ext4_get_acl,
+ .set_acl = ext4_set_acl,
+ .fiemap = ext4_fiemap,
+};
+
+const struct inode_operations ext4_special_inode_operations = {
+ .setattr = ext4_setattr,
+ .getattr = ext4_getattr,
+ .listxattr = ext4_listxattr,
+ .get_acl = ext4_get_acl,
+ .set_acl = ext4_set_acl,
+};