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Diffstat (limited to 'fs/ocfs2/dir.c')
-rw-r--r--fs/ocfs2/dir.c430
1 files changed, 423 insertions, 7 deletions
diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
index 0d5fdde959c..8e0ae022b2e 100644
--- a/fs/ocfs2/dir.c
+++ b/fs/ocfs2/dir.c
@@ -55,10 +55,16 @@
#include "journal.h"
#include "namei.h"
#include "suballoc.h"
+#include "super.h"
#include "uptodate.h"
#include "buffer_head_io.h"
+#define NAMEI_RA_CHUNKS 2
+#define NAMEI_RA_BLOCKS 4
+#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
+#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
+
static unsigned char ocfs2_filetype_table[] = {
DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
};
@@ -67,6 +73,347 @@ static int ocfs2_extend_dir(struct ocfs2_super *osb,
struct inode *dir,
struct buffer_head *parent_fe_bh,
struct buffer_head **new_de_bh);
+static int ocfs2_do_extend_dir(struct super_block *sb,
+ handle_t *handle,
+ struct inode *dir,
+ struct buffer_head *parent_fe_bh,
+ struct ocfs2_alloc_context *data_ac,
+ struct ocfs2_alloc_context *meta_ac,
+ struct buffer_head **new_bh);
+
+int ocfs2_check_dir_entry(struct inode * dir,
+ struct ocfs2_dir_entry * de,
+ struct buffer_head * bh,
+ unsigned long offset)
+{
+ const char *error_msg = NULL;
+ const int rlen = le16_to_cpu(de->rec_len);
+
+ if (rlen < OCFS2_DIR_REC_LEN(1))
+ error_msg = "rec_len is smaller than minimal";
+ else if (rlen % 4 != 0)
+ error_msg = "rec_len % 4 != 0";
+ else if (rlen < OCFS2_DIR_REC_LEN(de->name_len))
+ error_msg = "rec_len is too small for name_len";
+ else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize)
+ error_msg = "directory entry across blocks";
+
+ if (error_msg != NULL)
+ mlog(ML_ERROR, "bad entry in directory #%llu: %s - "
+ "offset=%lu, inode=%llu, rec_len=%d, name_len=%d\n",
+ (unsigned long long)OCFS2_I(dir)->ip_blkno, error_msg,
+ offset, (unsigned long long)le64_to_cpu(de->inode), rlen,
+ de->name_len);
+ return error_msg == NULL ? 1 : 0;
+}
+
+static inline int ocfs2_match(int len,
+ const char * const name,
+ struct ocfs2_dir_entry *de)
+{
+ if (len != de->name_len)
+ return 0;
+ if (!de->inode)
+ return 0;
+ return !memcmp(name, de->name, len);
+}
+
+/*
+ * Returns 0 if not found, -1 on failure, and 1 on success
+ */
+static int inline ocfs2_search_dirblock(struct buffer_head *bh,
+ struct inode *dir,
+ const char *name, int namelen,
+ unsigned long offset,
+ struct ocfs2_dir_entry **res_dir)
+{
+ struct ocfs2_dir_entry *de;
+ char *dlimit, *de_buf;
+ int de_len;
+ int ret = 0;
+
+ mlog_entry_void();
+
+ de_buf = bh->b_data;
+ dlimit = de_buf + dir->i_sb->s_blocksize;
+
+ while (de_buf < dlimit) {
+ /* this code is executed quadratically often */
+ /* do minimal checking `by hand' */
+
+ de = (struct ocfs2_dir_entry *) de_buf;
+
+ if (de_buf + namelen <= dlimit &&
+ ocfs2_match(namelen, name, de)) {
+ /* found a match - just to be sure, do a full check */
+ if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
+ ret = -1;
+ goto bail;
+ }
+ *res_dir = de;
+ ret = 1;
+ goto bail;
+ }
+
+ /* prevent looping on a bad block */
+ de_len = le16_to_cpu(de->rec_len);
+ if (de_len <= 0) {
+ ret = -1;
+ goto bail;
+ }
+
+ de_buf += de_len;
+ offset += de_len;
+ }
+
+bail:
+ mlog_exit(ret);
+ return ret;
+}
+
+struct buffer_head *ocfs2_find_entry(const char *name, int namelen,
+ struct inode *dir,
+ struct ocfs2_dir_entry **res_dir)
+{
+ struct super_block *sb;
+ struct buffer_head *bh_use[NAMEI_RA_SIZE];
+ struct buffer_head *bh, *ret = NULL;
+ unsigned long start, block, b;
+ int ra_max = 0; /* Number of bh's in the readahead
+ buffer, bh_use[] */
+ int ra_ptr = 0; /* Current index into readahead
+ buffer */
+ int num = 0;
+ int nblocks, i, err;
+
+ mlog_entry_void();
+
+ *res_dir = NULL;
+ sb = dir->i_sb;
+
+ nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
+ start = OCFS2_I(dir)->ip_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;
+ b = block;
+ for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
+ /*
+ * Terminate if we reach the end of the
+ * directory and must wrap, or if our
+ * search has finished at this block.
+ */
+ if (b >= nblocks || (num && block == start)) {
+ bh_use[ra_max] = NULL;
+ break;
+ }
+ num++;
+
+ bh = ocfs2_bread(dir, b++, &err, 1);
+ bh_use[ra_max] = bh;
+ }
+ }
+ if ((bh = bh_use[ra_ptr++]) == NULL)
+ goto next;
+ wait_on_buffer(bh);
+ if (!buffer_uptodate(bh)) {
+ /* read error, skip block & hope for the best */
+ ocfs2_error(dir->i_sb, "reading directory %llu, "
+ "offset %lu\n",
+ (unsigned long long)OCFS2_I(dir)->ip_blkno,
+ block);
+ brelse(bh);
+ goto next;
+ }
+ i = ocfs2_search_dirblock(bh, dir, name, namelen,
+ block << sb->s_blocksize_bits,
+ res_dir);
+ if (i == 1) {
+ OCFS2_I(dir)->ip_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 = i_size_read(dir) >> sb->s_blocksize_bits;
+ 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]);
+
+ mlog_exit_ptr(ret);
+ return ret;
+}
+
+/*
+ * ocfs2_delete_entry deletes a directory entry by merging it with the
+ * previous entry
+ */
+int ocfs2_delete_entry(handle_t *handle,
+ struct inode *dir,
+ struct ocfs2_dir_entry *de_del,
+ struct buffer_head *bh)
+{
+ struct ocfs2_dir_entry *de, *pde;
+ int i, status = -ENOENT;
+
+ mlog_entry("(0x%p, 0x%p, 0x%p, 0x%p)\n", handle, dir, de_del, bh);
+
+ i = 0;
+ pde = NULL;
+ de = (struct ocfs2_dir_entry *) bh->b_data;
+ while (i < bh->b_size) {
+ if (!ocfs2_check_dir_entry(dir, de, bh, i)) {
+ status = -EIO;
+ mlog_errno(status);
+ goto bail;
+ }
+ if (de == de_del) {
+ status = ocfs2_journal_access(handle, dir, bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (status < 0) {
+ status = -EIO;
+ mlog_errno(status);
+ goto bail;
+ }
+ if (pde)
+ pde->rec_len =
+ cpu_to_le16(le16_to_cpu(pde->rec_len) +
+ le16_to_cpu(de->rec_len));
+ else
+ de->inode = 0;
+ dir->i_version++;
+ status = ocfs2_journal_dirty(handle, bh);
+ goto bail;
+ }
+ i += le16_to_cpu(de->rec_len);
+ pde = de;
+ de = (struct ocfs2_dir_entry *)((char *)de + le16_to_cpu(de->rec_len));
+ }
+bail:
+ mlog_exit(status);
+ return status;
+}
+
+/* we don't always have a dentry for what we want to add, so people
+ * like orphan dir can call this instead.
+ *
+ * If you pass me insert_bh, I'll skip the search of the other dir
+ * blocks and put the record in there.
+ */
+int __ocfs2_add_entry(handle_t *handle,
+ struct inode *dir,
+ const char *name, int namelen,
+ struct inode *inode, u64 blkno,
+ struct buffer_head *parent_fe_bh,
+ struct buffer_head *insert_bh)
+{
+ unsigned long offset;
+ unsigned short rec_len;
+ struct ocfs2_dir_entry *de, *de1;
+ struct super_block *sb;
+ int retval, status;
+
+ mlog_entry_void();
+
+ sb = dir->i_sb;
+
+ if (!namelen)
+ return -EINVAL;
+
+ rec_len = OCFS2_DIR_REC_LEN(namelen);
+ offset = 0;
+ de = (struct ocfs2_dir_entry *) insert_bh->b_data;
+ while (1) {
+ BUG_ON((char *)de >= sb->s_blocksize + insert_bh->b_data);
+ /* These checks should've already been passed by the
+ * prepare function, but I guess we can leave them
+ * here anyway. */
+ if (!ocfs2_check_dir_entry(dir, de, insert_bh, offset)) {
+ retval = -ENOENT;
+ goto bail;
+ }
+ if (ocfs2_match(namelen, name, de)) {
+ retval = -EEXIST;
+ goto bail;
+ }
+ if (((le64_to_cpu(de->inode) == 0) &&
+ (le16_to_cpu(de->rec_len) >= rec_len)) ||
+ (le16_to_cpu(de->rec_len) >=
+ (OCFS2_DIR_REC_LEN(de->name_len) + rec_len))) {
+ dir->i_mtime = dir->i_ctime = CURRENT_TIME;
+ retval = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
+ if (retval < 0) {
+ mlog_errno(retval);
+ goto bail;
+ }
+
+ status = ocfs2_journal_access(handle, dir, insert_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ /* By now the buffer is marked for journaling */
+ offset += le16_to_cpu(de->rec_len);
+ if (le64_to_cpu(de->inode)) {
+ de1 = (struct ocfs2_dir_entry *)((char *) de +
+ OCFS2_DIR_REC_LEN(de->name_len));
+ de1->rec_len =
+ cpu_to_le16(le16_to_cpu(de->rec_len) -
+ OCFS2_DIR_REC_LEN(de->name_len));
+ de->rec_len = cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
+ de = de1;
+ }
+ de->file_type = OCFS2_FT_UNKNOWN;
+ if (blkno) {
+ de->inode = cpu_to_le64(blkno);
+ ocfs2_set_de_type(de, inode->i_mode);
+ } else
+ de->inode = 0;
+ de->name_len = namelen;
+ memcpy(de->name, name, namelen);
+
+ dir->i_version++;
+ status = ocfs2_journal_dirty(handle, insert_bh);
+ retval = 0;
+ goto bail;
+ }
+ offset += le16_to_cpu(de->rec_len);
+ de = (struct ocfs2_dir_entry *) ((char *) de + le16_to_cpu(de->rec_len));
+ }
+
+ /* when you think about it, the assert above should prevent us
+ * from ever getting here. */
+ retval = -ENOSPC;
+bail:
+
+ mlog_exit(retval);
+ return retval;
+}
+
/*
* ocfs2_readdir()
*
@@ -347,14 +694,83 @@ int ocfs2_empty_dir(struct inode *inode)
return 1;
}
+int ocfs2_fill_new_dir(struct ocfs2_super *osb,
+ handle_t *handle,
+ struct inode *parent,
+ struct inode *inode,
+ struct buffer_head *fe_bh,
+ struct ocfs2_alloc_context *data_ac)
+{
+ int status;
+ struct buffer_head *new_bh = NULL;
+ struct ocfs2_dir_entry *de = NULL;
+
+ mlog_entry_void();
+
+ status = ocfs2_do_extend_dir(osb->sb, handle, inode, fe_bh,
+ data_ac, NULL, &new_bh);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ ocfs2_set_new_buffer_uptodate(inode, new_bh);
+
+ status = ocfs2_journal_access(handle, inode, new_bh,
+ OCFS2_JOURNAL_ACCESS_CREATE);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+ memset(new_bh->b_data, 0, osb->sb->s_blocksize);
+
+ de = (struct ocfs2_dir_entry *) new_bh->b_data;
+ de->inode = cpu_to_le64(OCFS2_I(inode)->ip_blkno);
+ de->name_len = 1;
+ de->rec_len =
+ cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
+ strcpy(de->name, ".");
+ ocfs2_set_de_type(de, S_IFDIR);
+ de = (struct ocfs2_dir_entry *) ((char *)de + le16_to_cpu(de->rec_len));
+ de->inode = cpu_to_le64(OCFS2_I(parent)->ip_blkno);
+ de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize -
+ OCFS2_DIR_REC_LEN(1));
+ de->name_len = 2;
+ strcpy(de->name, "..");
+ ocfs2_set_de_type(de, S_IFDIR);
+
+ status = ocfs2_journal_dirty(handle, new_bh);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ i_size_write(inode, inode->i_sb->s_blocksize);
+ inode->i_nlink = 2;
+ inode->i_blocks = ocfs2_inode_sector_count(inode);
+ status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ status = 0;
+bail:
+ if (new_bh)
+ brelse(new_bh);
+
+ mlog_exit(status);
+ return status;
+}
+
/* returns a bh of the 1st new block in the allocation. */
-int ocfs2_do_extend_dir(struct super_block *sb,
- handle_t *handle,
- struct inode *dir,
- struct buffer_head *parent_fe_bh,
- struct ocfs2_alloc_context *data_ac,
- struct ocfs2_alloc_context *meta_ac,
- struct buffer_head **new_bh)
+static int ocfs2_do_extend_dir(struct super_block *sb,
+ handle_t *handle,
+ struct inode *dir,
+ struct buffer_head *parent_fe_bh,
+ struct ocfs2_alloc_context *data_ac,
+ struct ocfs2_alloc_context *meta_ac,
+ struct buffer_head **new_bh)
{
int status;
int extend;