diff options
Diffstat (limited to 'fs/reiserfs/dir.c')
-rw-r--r-- | fs/reiserfs/dir.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/fs/reiserfs/dir.c b/fs/reiserfs/dir.c new file mode 100644 index 00000000000..d1514a9b051 --- /dev/null +++ b/fs/reiserfs/dir.c @@ -0,0 +1,275 @@ +/* + * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README + */ + +#include <linux/config.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/reiserfs_fs.h> +#include <linux/stat.h> +#include <linux/smp_lock.h> +#include <linux/buffer_head.h> +#include <asm/uaccess.h> + +extern struct reiserfs_key MIN_KEY; + +static int reiserfs_readdir (struct file *, void *, filldir_t); +static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry, int datasync) ; + +struct file_operations reiserfs_dir_operations = { + .read = generic_read_dir, + .readdir = reiserfs_readdir, + .fsync = reiserfs_dir_fsync, + .ioctl = reiserfs_ioctl, +}; + +static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry, int datasync) { + struct inode *inode = dentry->d_inode; + int err; + reiserfs_write_lock(inode->i_sb); + err = reiserfs_commit_for_inode(inode) ; + reiserfs_write_unlock(inode->i_sb) ; + if (err < 0) + return err; + return 0; +} + + +#define store_ih(where,what) copy_item_head (where, what) + +// +static int reiserfs_readdir (struct file * filp, void * dirent, filldir_t filldir) +{ + struct inode *inode = filp->f_dentry->d_inode; + struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */ + INITIALIZE_PATH (path_to_entry); + struct buffer_head * bh; + int item_num, entry_num; + const struct reiserfs_key * rkey; + struct item_head * ih, tmp_ih; + int search_res; + char * local_buf; + loff_t next_pos; + char small_buf[32] ; /* avoid kmalloc if we can */ + struct reiserfs_dir_entry de; + int ret = 0; + + reiserfs_write_lock(inode->i_sb); + + reiserfs_check_lock_depth(inode->i_sb, "readdir") ; + + /* form key for search the next directory entry using f_pos field of + file structure */ + make_cpu_key (&pos_key, inode, (filp->f_pos) ? (filp->f_pos) : DOT_OFFSET, + TYPE_DIRENTRY, 3); + next_pos = cpu_key_k_offset (&pos_key); + + /* reiserfs_warning (inode->i_sb, "reiserfs_readdir 1: f_pos = %Ld", filp->f_pos);*/ + + path_to_entry.reada = PATH_READA; + while (1) { + research: + /* search the directory item, containing entry with specified key */ + search_res = search_by_entry_key (inode->i_sb, &pos_key, &path_to_entry, &de); + if (search_res == IO_ERROR) { + // FIXME: we could just skip part of directory which could + // not be read + ret = -EIO; + goto out; + } + entry_num = de.de_entry_num; + bh = de.de_bh; + item_num = de.de_item_num; + ih = de.de_ih; + store_ih (&tmp_ih, ih); + + /* we must have found item, that is item of this directory, */ + RFALSE( COMP_SHORT_KEYS (&(ih->ih_key), &pos_key), + "vs-9000: found item %h does not match to dir we readdir %K", + ih, &pos_key); + RFALSE( item_num > B_NR_ITEMS (bh) - 1, + "vs-9005 item_num == %d, item amount == %d", + item_num, B_NR_ITEMS (bh)); + + /* and entry must be not more than number of entries in the item */ + RFALSE( I_ENTRY_COUNT (ih) < entry_num, + "vs-9010: entry number is too big %d (%d)", + entry_num, I_ENTRY_COUNT (ih)); + + if (search_res == POSITION_FOUND || entry_num < I_ENTRY_COUNT (ih)) { + /* go through all entries in the directory item beginning from the entry, that has been found */ + struct reiserfs_de_head * deh = B_I_DEH (bh, ih) + entry_num; + + for (; entry_num < I_ENTRY_COUNT (ih); entry_num ++, deh ++) { + int d_reclen; + char * d_name; + off_t d_off; + ino_t d_ino; + + if (!de_visible (deh)) + /* it is hidden entry */ + continue; + d_reclen = entry_length (bh, ih, entry_num); + d_name = B_I_DEH_ENTRY_FILE_NAME (bh, ih, deh); + if (!d_name[d_reclen - 1]) + d_reclen = strlen (d_name); + + if (d_reclen > REISERFS_MAX_NAME(inode->i_sb->s_blocksize)){ + /* too big to send back to VFS */ + continue ; + } + + /* Ignore the .reiserfs_priv entry */ + if (reiserfs_xattrs (inode->i_sb) && + !old_format_only(inode->i_sb) && + filp->f_dentry == inode->i_sb->s_root && + REISERFS_SB(inode->i_sb)->priv_root && + REISERFS_SB(inode->i_sb)->priv_root->d_inode && + deh_objectid(deh) == le32_to_cpu (INODE_PKEY(REISERFS_SB(inode->i_sb)->priv_root->d_inode)->k_objectid)) { + continue; + } + + d_off = deh_offset (deh); + filp->f_pos = d_off ; + d_ino = deh_objectid (deh); + if (d_reclen <= 32) { + local_buf = small_buf ; + } else { + local_buf = reiserfs_kmalloc(d_reclen, GFP_NOFS, inode->i_sb) ; + if (!local_buf) { + pathrelse (&path_to_entry); + ret = -ENOMEM ; + goto out; + } + if (item_moved (&tmp_ih, &path_to_entry)) { + reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ; + goto research; + } + } + // Note, that we copy name to user space via temporary + // buffer (local_buf) because filldir will block if + // user space buffer is swapped out. At that time + // entry can move to somewhere else + memcpy (local_buf, d_name, d_reclen); + if (filldir (dirent, local_buf, d_reclen, d_off, d_ino, + DT_UNKNOWN) < 0) { + if (local_buf != small_buf) { + reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ; + } + goto end; + } + if (local_buf != small_buf) { + reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ; + } + + // next entry should be looked for with such offset + next_pos = deh_offset (deh) + 1; + + if (item_moved (&tmp_ih, &path_to_entry)) { + goto research; + } + } /* for */ + } + + if (item_num != B_NR_ITEMS (bh) - 1) + // end of directory has been reached + goto end; + + /* item we went through is last item of node. Using right + delimiting key check is it directory end */ + rkey = get_rkey (&path_to_entry, inode->i_sb); + if (! comp_le_keys (rkey, &MIN_KEY)) { + /* set pos_key to key, that is the smallest and greater + that key of the last entry in the item */ + set_cpu_key_k_offset (&pos_key, next_pos); + continue; + } + + if ( COMP_SHORT_KEYS (rkey, &pos_key)) { + // end of directory has been reached + goto end; + } + + /* directory continues in the right neighboring block */ + set_cpu_key_k_offset (&pos_key, le_key_k_offset (KEY_FORMAT_3_5, rkey)); + + } /* while */ + + + end: + filp->f_pos = next_pos; + pathrelse (&path_to_entry); + reiserfs_check_path(&path_to_entry) ; + out: + reiserfs_write_unlock(inode->i_sb); + return ret; +} + +/* compose directory item containing "." and ".." entries (entries are + not aligned to 4 byte boundary) */ +/* the last four params are LE */ +void make_empty_dir_item_v1 (char * body, __u32 dirid, __u32 objid, + __u32 par_dirid, __u32 par_objid) +{ + struct reiserfs_de_head * deh; + + memset (body, 0, EMPTY_DIR_SIZE_V1); + deh = (struct reiserfs_de_head *)body; + + /* direntry header of "." */ + put_deh_offset( &(deh[0]), DOT_OFFSET ); + /* these two are from make_le_item_head, and are are LE */ + deh[0].deh_dir_id = dirid; + deh[0].deh_objectid = objid; + deh[0].deh_state = 0; /* Endian safe if 0 */ + put_deh_location( &(deh[0]), EMPTY_DIR_SIZE_V1 - strlen( "." )); + mark_de_visible(&(deh[0])); + + /* direntry header of ".." */ + put_deh_offset( &(deh[1]), DOT_DOT_OFFSET); + /* key of ".." for the root directory */ + /* these two are from the inode, and are are LE */ + deh[1].deh_dir_id = par_dirid; + deh[1].deh_objectid = par_objid; + deh[1].deh_state = 0; /* Endian safe if 0 */ + put_deh_location( &(deh[1]), deh_location( &(deh[0]) ) - strlen( ".." ) ); + mark_de_visible(&(deh[1])); + + /* copy ".." and "." */ + memcpy (body + deh_location( &(deh[0]) ), ".", 1); + memcpy (body + deh_location( &(deh[1]) ), "..", 2); +} + +/* compose directory item containing "." and ".." entries */ +void make_empty_dir_item (char * body, __u32 dirid, __u32 objid, + __u32 par_dirid, __u32 par_objid) +{ + struct reiserfs_de_head * deh; + + memset (body, 0, EMPTY_DIR_SIZE); + deh = (struct reiserfs_de_head *)body; + + /* direntry header of "." */ + put_deh_offset( &(deh[0]), DOT_OFFSET ); + /* these two are from make_le_item_head, and are are LE */ + deh[0].deh_dir_id = dirid; + deh[0].deh_objectid = objid; + deh[0].deh_state = 0; /* Endian safe if 0 */ + put_deh_location( &(deh[0]), EMPTY_DIR_SIZE - ROUND_UP( strlen( "." ) ) ); + mark_de_visible(&(deh[0])); + + /* direntry header of ".." */ + put_deh_offset( &(deh[1]), DOT_DOT_OFFSET ); + /* key of ".." for the root directory */ + /* these two are from the inode, and are are LE */ + deh[1].deh_dir_id = par_dirid; + deh[1].deh_objectid = par_objid; + deh[1].deh_state = 0; /* Endian safe if 0 */ + put_deh_location( &(deh[1]), deh_location( &(deh[0])) - ROUND_UP( strlen( ".." ) ) ); + mark_de_visible(&(deh[1])); + + /* copy ".." and "." */ + memcpy (body + deh_location( &(deh[0]) ), ".", 1); + memcpy (body + deh_location( &(deh[1]) ), "..", 2); +} |