[PATCH] ufs: directory and page cache: from blocks to pages
Change function in fs/ufs/dir.c and fs/ufs/namei.c to work with pages
instead of straight work with blocks. It fixed such bugs:
* for i in `seq 1 1000`; do touch $i; done - crash system
* mkdir create directory without "." and ".." entries
Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/ufs/dir.c b/fs/ufs/dir.c
index 1a56120..9473df5 100644
--- a/fs/ufs/dir.c
+++ b/fs/ufs/dir.c
@@ -11,13 +11,15 @@
* 4.4BSD (FreeBSD) support added on February 1st 1998 by
* Niels Kristian Bech Jensen <nkbj@image.dk> partially based
* on code by Martin von Loewis <martin@mira.isdn.cs.tu-berlin.de>.
+ *
+ * Migration to usage of "page cache" on May 2006 by
+ * Evgeniy Dushistov <dushistov@mail.ru> based on ext2 code base.
*/
#include <linux/time.h>
#include <linux/fs.h>
#include <linux/ufs_fs.h>
#include <linux/smp_lock.h>
-#include <linux/buffer_head.h>
#include <linux/sched.h>
#include "swab.h"
@@ -31,11 +33,6 @@
#define UFSD(x)
#endif
-static int
-ufs_check_dir_entry (const char *, struct inode *, struct ufs_dir_entry *,
- struct buffer_head *, unsigned long);
-
-
/*
* NOTE! unlike strncmp, ufs_match returns 1 for success, 0 for failure.
*
@@ -51,495 +48,540 @@
return !memcmp(name, de->d_name, len);
}
-/*
- * This is blatantly stolen from ext2fs
- */
-static int
-ufs_readdir (struct file * filp, void * dirent, filldir_t filldir)
+static int ufs_commit_chunk(struct page *page, unsigned from, unsigned to)
{
- struct inode *inode = filp->f_dentry->d_inode;
- int error = 0;
- unsigned long offset, lblk;
- int i, stored;
- struct buffer_head * bh;
- struct ufs_dir_entry * de;
- struct super_block * sb;
- int de_reclen;
- unsigned flags;
- u64 blk= 0L;
+ struct inode *dir = page->mapping->host;
+ int err = 0;
+ dir->i_version++;
+ page->mapping->a_ops->commit_write(NULL, page, from, to);
+ if (IS_DIRSYNC(dir))
+ err = write_one_page(page, 1);
+ else
+ unlock_page(page);
+ return err;
+}
- lock_kernel();
+static inline void ufs_put_page(struct page *page)
+{
+ kunmap(page);
+ page_cache_release(page);
+}
- sb = inode->i_sb;
- flags = UFS_SB(sb)->s_flags;
+static inline unsigned long ufs_dir_pages(struct inode *inode)
+{
+ return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
+}
- UFSD(("ENTER, ino %lu f_pos %lu\n", inode->i_ino, (unsigned long) filp->f_pos))
-
- stored = 0;
- bh = NULL;
- offset = filp->f_pos & (sb->s_blocksize - 1);
-
- while (!error && !stored && filp->f_pos < inode->i_size) {
- lblk = (filp->f_pos) >> sb->s_blocksize_bits;
- blk = ufs_frag_map(inode, lblk);
- if (!blk || !(bh = sb_bread(sb, blk))) {
- /* XXX - error - skip to the next block */
- printk("ufs_readdir: "
- "dir inode %lu has a hole at offset %lu\n",
- inode->i_ino, (unsigned long int)filp->f_pos);
- filp->f_pos += sb->s_blocksize - offset;
- continue;
- }
-
-revalidate:
- /* If the dir block has changed since the last call to
- * readdir(2), then we might be pointing to an invalid
- * dirent right now. Scan from the start of the block
- * to make sure. */
- if (filp->f_version != inode->i_version) {
- for (i = 0; i < sb->s_blocksize && i < offset; ) {
- de = (struct ufs_dir_entry *)(bh->b_data + i);
- /* It's too expensive to do a full
- * dirent test each time round this
- * loop, but we do have to test at
- * least that it is non-zero. A
- * failure will be detected in the
- * dirent test below. */
- de_reclen = fs16_to_cpu(sb, de->d_reclen);
- if (de_reclen < 1)
- break;
- i += de_reclen;
- }
- offset = i;
- filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
- | offset;
- filp->f_version = inode->i_version;
- }
-
- while (!error && filp->f_pos < inode->i_size
- && offset < sb->s_blocksize) {
- de = (struct ufs_dir_entry *) (bh->b_data + offset);
- /* XXX - put in a real ufs_check_dir_entry() */
- if ((de->d_reclen == 0) || (ufs_get_de_namlen(sb, de) == 0)) {
- filp->f_pos = (filp->f_pos &
- (sb->s_blocksize - 1)) +
- sb->s_blocksize;
- brelse(bh);
- unlock_kernel();
- return stored;
- }
- if (!ufs_check_dir_entry ("ufs_readdir", inode, de,
- bh, offset)) {
- /* On error, skip the f_pos to the
- next block. */
- filp->f_pos = (filp->f_pos |
- (sb->s_blocksize - 1)) +
- 1;
- brelse (bh);
- unlock_kernel();
- return stored;
- }
- offset += fs16_to_cpu(sb, de->d_reclen);
- if (de->d_ino) {
- /* We might block in the next section
- * if the data destination is
- * currently swapped out. So, use a
- * version stamp to detect whether or
- * not the directory has been modified
- * during the copy operation. */
- unsigned long version = filp->f_version;
- unsigned char d_type = DT_UNKNOWN;
-
- UFSD(("filldir(%s,%u)\n", de->d_name,
- fs32_to_cpu(sb, de->d_ino)))
- UFSD(("namlen %u\n", ufs_get_de_namlen(sb, de)))
-
- if ((flags & UFS_DE_MASK) == UFS_DE_44BSD)
- d_type = de->d_u.d_44.d_type;
- error = filldir(dirent, de->d_name,
- ufs_get_de_namlen(sb, de), filp->f_pos,
- fs32_to_cpu(sb, de->d_ino), d_type);
- if (error)
- break;
- if (version != filp->f_version)
- goto revalidate;
- stored ++;
- }
- filp->f_pos += fs16_to_cpu(sb, de->d_reclen);
- }
- offset = 0;
- brelse (bh);
+ino_t ufs_inode_by_name(struct inode *dir, struct dentry *dentry)
+{
+ ino_t res = 0;
+ struct ufs_dir_entry *de;
+ struct page *page;
+
+ de = ufs_find_entry(dir, dentry, &page);
+ if (de) {
+ res = fs32_to_cpu(dir->i_sb, de->d_ino);
+ ufs_put_page(page);
}
- unlock_kernel();
- return 0;
+ return res;
+}
+
+
+/* Releases the page */
+void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de,
+ struct page *page, struct inode *inode)
+{
+ unsigned from = (char *) de - (char *) page_address(page);
+ unsigned to = from + fs16_to_cpu(dir->i_sb, de->d_reclen);
+ int err;
+
+ lock_page(page);
+ err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
+ BUG_ON(err);
+ de->d_ino = cpu_to_fs32(dir->i_sb, inode->i_ino);
+ ufs_set_de_type(dir->i_sb, de, inode->i_mode);
+ err = ufs_commit_chunk(page, from, to);
+ ufs_put_page(page);
+ dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
+ mark_inode_dirty(dir);
+}
+
+
+static void ufs_check_page(struct page *page)
+{
+ struct inode *dir = page->mapping->host;
+ struct super_block *sb = dir->i_sb;
+ char *kaddr = page_address(page);
+ unsigned offs, rec_len;
+ unsigned limit = PAGE_CACHE_SIZE;
+ struct ufs_dir_entry *p;
+ char *error;
+
+ if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
+ limit = dir->i_size & ~PAGE_CACHE_MASK;
+ if (limit & (UFS_SECTOR_SIZE - 1))
+ goto Ebadsize;
+ if (!limit)
+ goto out;
+ }
+ for (offs = 0; offs <= limit - UFS_DIR_REC_LEN(1); offs += rec_len) {
+ p = (struct ufs_dir_entry *)(kaddr + offs);
+ rec_len = fs16_to_cpu(sb, p->d_reclen);
+
+ if (rec_len < UFS_DIR_REC_LEN(1))
+ goto Eshort;
+ if (rec_len & 3)
+ goto Ealign;
+ if (rec_len < UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, p)))
+ goto Enamelen;
+ if (((offs + rec_len - 1) ^ offs) & ~(UFS_SECTOR_SIZE-1))
+ goto Espan;
+ if (fs32_to_cpu(sb, p->d_ino) > (UFS_SB(sb)->s_uspi->s_ipg *
+ UFS_SB(sb)->s_uspi->s_ncg))
+ goto Einumber;
+ }
+ if (offs != limit)
+ goto Eend;
+out:
+ SetPageChecked(page);
+ return;
+
+ /* Too bad, we had an error */
+
+Ebadsize:
+ ufs_error(sb, "ufs_check_page",
+ "size of directory #%lu is not a multiple of chunk size",
+ dir->i_ino
+ );
+ goto fail;
+Eshort:
+ error = "rec_len is smaller than minimal";
+ goto bad_entry;
+Ealign:
+ error = "unaligned directory entry";
+ goto bad_entry;
+Enamelen:
+ error = "rec_len is too small for name_len";
+ goto bad_entry;
+Espan:
+ error = "directory entry across blocks";
+ goto bad_entry;
+Einumber:
+ error = "inode out of bounds";
+bad_entry:
+ ufs_error (sb, "ufs_check_page", "bad entry in directory #%lu: %s - "
+ "offset=%lu, rec_len=%d, name_len=%d",
+ dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
+ rec_len, ufs_get_de_namlen(sb, p));
+ goto fail;
+Eend:
+ p = (struct ufs_dir_entry *)(kaddr + offs);
+ ufs_error (sb, "ext2_check_page",
+ "entry in directory #%lu spans the page boundary"
+ "offset=%lu",
+ dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs);
+fail:
+ SetPageChecked(page);
+ SetPageError(page);
+}
+
+static struct page *ufs_get_page(struct inode *dir, unsigned long n)
+{
+ struct address_space *mapping = dir->i_mapping;
+ struct page *page = read_cache_page(mapping, n,
+ (filler_t*)mapping->a_ops->readpage, NULL);
+ if (!IS_ERR(page)) {
+ wait_on_page_locked(page);
+ kmap(page);
+ if (!PageUptodate(page))
+ goto fail;
+ if (!PageChecked(page))
+ ufs_check_page(page);
+ if (PageError(page))
+ goto fail;
+ }
+ return page;
+
+fail:
+ ufs_put_page(page);
+ return ERR_PTR(-EIO);
}
/*
- * define how far ahead to read directories while searching them.
+ * Return the offset into page `page_nr' of the last valid
+ * byte in that page, plus one.
*/
-#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
+ufs_last_byte(struct inode *inode, unsigned long page_nr)
+{
+ unsigned last_byte = inode->i_size;
+
+ last_byte -= page_nr << PAGE_CACHE_SHIFT;
+ if (last_byte > PAGE_CACHE_SIZE)
+ last_byte = PAGE_CACHE_SIZE;
+ return last_byte;
+}
+
+static inline struct ufs_dir_entry *
+ufs_next_entry(struct super_block *sb, struct ufs_dir_entry *p)
+{
+ return (struct ufs_dir_entry *)((char *)p +
+ fs16_to_cpu(sb, p->d_reclen));
+}
+
+struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p)
+{
+ struct page *page = ufs_get_page(dir, 0);
+ struct ufs_dir_entry *de = NULL;
+
+ if (!IS_ERR(page)) {
+ de = ufs_next_entry(dir->i_sb,
+ (struct ufs_dir_entry *)page_address(page));
+ *p = page;
+ }
+ return de;
+}
/*
* ufs_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_bh). It does NOT read the inode of the
- * entry - you'll have to do that yourself if you want to.
+ * returns the page in which the entry was found, and the entry itself
+ * (as a parameter - res_dir). Page is returned mapped and unlocked.
+ * Entry is guaranteed to be valid.
*/
-struct ufs_dir_entry * ufs_find_entry (struct dentry *dentry,
- struct buffer_head ** res_bh)
-{
- struct super_block * sb;
- struct buffer_head * bh_use[NAMEI_RA_SIZE];
- struct buffer_head * bh_read[NAMEI_RA_SIZE];
- unsigned long offset;
- int block, toread, i, err;
- struct inode *dir = dentry->d_parent->d_inode;
- const char *name = dentry->d_name.name;
- int namelen = dentry->d_name.len;
-
- UFSD(("ENTER, dir_ino %lu, name %s, namlen %u\n", dir->i_ino, name, namelen))
-
- *res_bh = NULL;
-
- sb = dir->i_sb;
-
- if (namelen > UFS_MAXNAMLEN)
- return NULL;
-
- memset (bh_use, 0, sizeof (bh_use));
- toread = 0;
- for (block = 0; block < NAMEI_RA_SIZE; ++block) {
- struct buffer_head * bh;
-
- if ((block << sb->s_blocksize_bits) >= dir->i_size)
- break;
- bh = ufs_getfrag (dir, block, 0, &err);
- bh_use[block] = bh;
- if (bh && !buffer_uptodate(bh))
- bh_read[toread++] = bh;
- }
-
- for (block = 0, offset = 0; offset < dir->i_size; block++) {
- struct buffer_head * bh;
- struct ufs_dir_entry * de;
- char * dlimit;
-
- if ((block % NAMEI_RA_BLOCKS) == 0 && toread) {
- ll_rw_block (READ, toread, bh_read);
- toread = 0;
- }
- bh = bh_use[block % NAMEI_RA_SIZE];
- if (!bh) {
- ufs_error (sb, "ufs_find_entry",
- "directory #%lu contains a hole at offset %lu",
- dir->i_ino, offset);
- offset += sb->s_blocksize;
- continue;
- }
- wait_on_buffer (bh);
- if (!buffer_uptodate(bh)) {
- /*
- * read error: all bets are off
- */
- break;
- }
-
- de = (struct ufs_dir_entry *) bh->b_data;
- dlimit = bh->b_data + sb->s_blocksize;
- while ((char *) de < dlimit && offset < dir->i_size) {
- /* this code is executed quadratically often */
- /* do minimal checking by hand */
- int de_len;
-
- if ((char *) de + namelen <= dlimit &&
- ufs_match(sb, namelen, name, de)) {
- /* found a match -
- just to be sure, do a full check */
- if (!ufs_check_dir_entry("ufs_find_entry",
- dir, de, bh, offset))
- goto failed;
- for (i = 0; i < NAMEI_RA_SIZE; ++i) {
- if (bh_use[i] != bh)
- brelse (bh_use[i]);
- }
- *res_bh = bh;
- return de;
- }
- /* prevent looping on a bad block */
- de_len = fs16_to_cpu(sb, de->d_reclen);
- if (de_len <= 0)
- goto failed;
- offset += de_len;
- de = (struct ufs_dir_entry *) ((char *) de + de_len);
- }
-
- brelse (bh);
- if (((block + NAMEI_RA_SIZE) << sb->s_blocksize_bits ) >=
- dir->i_size)
- bh = NULL;
- else
- bh = ufs_getfrag (dir, block + NAMEI_RA_SIZE, 0, &err);
- bh_use[block % NAMEI_RA_SIZE] = bh;
- if (bh && !buffer_uptodate(bh))
- bh_read[toread++] = bh;
- }
-
-failed:
- for (i = 0; i < NAMEI_RA_SIZE; ++i) brelse (bh_use[i]);
- UFSD(("EXIT\n"))
- return NULL;
-}
-
-static int
-ufs_check_dir_entry (const char *function, struct inode *dir,
- struct ufs_dir_entry *de, struct buffer_head *bh,
- unsigned long offset)
+struct ufs_dir_entry *ufs_find_entry(struct inode *dir, struct dentry *dentry,
+ struct page **res_page)
{
struct super_block *sb = dir->i_sb;
- const char *error_msg = NULL;
- int rlen = fs16_to_cpu(sb, de->d_reclen);
+ const char *name = dentry->d_name.name;
+ int namelen = dentry->d_name.len;
+ unsigned reclen = UFS_DIR_REC_LEN(namelen);
+ unsigned long start, n;
+ unsigned long npages = ufs_dir_pages(dir);
+ struct page *page = NULL;
+ struct ufs_dir_entry *de;
- if (rlen < UFS_DIR_REC_LEN(1))
- error_msg = "reclen is smaller than minimal";
- else if (rlen % 4 != 0)
- error_msg = "reclen % 4 != 0";
- else if (rlen < UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)))
- error_msg = "reclen is too small for namlen";
- else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize)
- error_msg = "directory entry across blocks";
- else if (fs32_to_cpu(sb, de->d_ino) > (UFS_SB(sb)->s_uspi->s_ipg *
- UFS_SB(sb)->s_uspi->s_ncg))
- error_msg = "inode out of bounds";
+ UFSD(("ENTER, dir_ino %lu, name %s, namlen %u\n", dir->i_ino, name, namelen));
- if (error_msg != NULL)
- ufs_error (sb, function, "bad entry in directory #%lu, size %Lu: %s - "
- "offset=%lu, inode=%lu, reclen=%d, namlen=%d",
- dir->i_ino, dir->i_size, error_msg, offset,
- (unsigned long)fs32_to_cpu(sb, de->d_ino),
- rlen, ufs_get_de_namlen(sb, de));
-
- return (error_msg == NULL ? 1 : 0);
-}
+ if (npages == 0 || namelen > UFS_MAXNAMLEN)
+ goto out;
-struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct buffer_head **p)
-{
- int err;
- struct buffer_head *bh = ufs_bread (dir, 0, 0, &err);
- struct ufs_dir_entry *res = NULL;
+ /* OFFSET_CACHE */
+ *res_page = NULL;
- if (bh) {
- res = (struct ufs_dir_entry *) bh->b_data;
- res = (struct ufs_dir_entry *)((char *)res +
- fs16_to_cpu(dir->i_sb, res->d_reclen));
- }
- *p = bh;
- return res;
-}
-ino_t ufs_inode_by_name(struct inode * dir, struct dentry *dentry)
-{
- ino_t res = 0;
- struct ufs_dir_entry * de;
- struct buffer_head *bh;
+ /* start = ei->i_dir_start_lookup; */
+ start = 0;
+ if (start >= npages)
+ start = 0;
+ n = start;
+ do {
+ char *kaddr;
+ page = ufs_get_page(dir, n);
+ if (!IS_ERR(page)) {
+ kaddr = page_address(page);
+ de = (struct ufs_dir_entry *) kaddr;
+ kaddr += ufs_last_byte(dir, n) - reclen;
+ while ((char *) de <= kaddr) {
+ if (de->d_reclen == 0) {
+ ufs_error(dir->i_sb, __FUNCTION__,
+ "zero-length directory entry");
+ ufs_put_page(page);
+ goto out;
+ }
+ if (ufs_match(sb, namelen, name, de))
+ goto found;
+ de = ufs_next_entry(sb, de);
+ }
+ ufs_put_page(page);
+ }
+ if (++n >= npages)
+ n = 0;
+ } while (n != start);
+out:
+ return NULL;
- de = ufs_find_entry (dentry, &bh);
- if (de) {
- res = fs32_to_cpu(dir->i_sb, de->d_ino);
- brelse(bh);
- }
- return res;
-}
-
-void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de,
- struct buffer_head *bh, struct inode *inode)
-{
- dir->i_version++;
- de->d_ino = cpu_to_fs32(dir->i_sb, inode->i_ino);
- mark_buffer_dirty(bh);
- if (IS_DIRSYNC(dir))
- sync_dirty_buffer(bh);
- brelse (bh);
+found:
+ *res_page = page;
+ /* ei->i_dir_start_lookup = n; */
+ return de;
}
/*
- * ufs_add_entry()
- *
- * adds a file entry to the specified directory, using the same
- * semantics as ufs_find_entry(). It returns NULL if it failed.
+ * Parent is locked.
*/
int ufs_add_link(struct dentry *dentry, struct inode *inode)
{
- struct super_block * sb;
- struct ufs_sb_private_info * uspi;
- unsigned long offset;
- unsigned fragoff;
- unsigned short rec_len;
- struct buffer_head * bh;
- struct ufs_dir_entry * de, * de1;
struct inode *dir = dentry->d_parent->d_inode;
const char *name = dentry->d_name.name;
int namelen = dentry->d_name.len;
+ struct super_block *sb = dir->i_sb;
+ unsigned reclen = UFS_DIR_REC_LEN(namelen);
+ unsigned short rec_len, name_len;
+ struct page *page = NULL;
+ struct ufs_dir_entry *de;
+ unsigned long npages = ufs_dir_pages(dir);
+ unsigned long n;
+ char *kaddr;
+ unsigned from, to;
int err;
- UFSD(("ENTER, name %s, namelen %u\n", name, namelen))
-
- sb = dir->i_sb;
- uspi = UFS_SB(sb)->s_uspi;
+ UFSD(("ENTER, name %s, namelen %u\n", name, namelen));
- if (!namelen)
- return -EINVAL;
- bh = ufs_bread (dir, 0, 0, &err);
- if (!bh)
- return err;
- rec_len = UFS_DIR_REC_LEN(namelen);
- offset = 0;
- de = (struct ufs_dir_entry *) bh->b_data;
- while (1) {
- if ((char *)de >= UFS_SECTOR_SIZE + bh->b_data) {
- fragoff = offset & ~uspi->s_fmask;
- if (fragoff != 0 && fragoff != UFS_SECTOR_SIZE)
- ufs_error (sb, "ufs_add_entry", "internal error"
- " fragoff %u", fragoff);
- if (!fragoff) {
- brelse (bh);
- bh = ufs_bread (dir, offset >> sb->s_blocksize_bits, 1, &err);
- if (!bh)
- return err;
- }
- if (dir->i_size <= offset) {
- if (dir->i_size == 0) {
- brelse(bh);
- return -ENOENT;
- }
- de = (struct ufs_dir_entry *) (bh->b_data + fragoff);
- de->d_ino = 0;
+ /*
+ * We take care of directory expansion in the same loop.
+ * This code plays outside i_size, so it locks the page
+ * to protect that region.
+ */
+ for (n = 0; n <= npages; n++) {
+ char *dir_end;
+
+ page = ufs_get_page(dir, n);
+ err = PTR_ERR(page);
+ if (IS_ERR(page))
+ goto out;
+ lock_page(page);
+ kaddr = page_address(page);
+ dir_end = kaddr + ufs_last_byte(dir, n);
+ de = (struct ufs_dir_entry *)kaddr;
+ kaddr += PAGE_CACHE_SIZE - reclen;
+ while ((char *)de <= kaddr) {
+ if ((char *)de == dir_end) {
+ /* We hit i_size */
+ name_len = 0;
+ rec_len = UFS_SECTOR_SIZE;
de->d_reclen = cpu_to_fs16(sb, UFS_SECTOR_SIZE);
- ufs_set_de_namlen(sb, de, 0);
- dir->i_size = offset + UFS_SECTOR_SIZE;
- mark_inode_dirty(dir);
- } else {
- de = (struct ufs_dir_entry *) bh->b_data;
+ de->d_ino = 0;
+ goto got_it;
}
+ if (de->d_reclen == 0) {
+ ufs_error(dir->i_sb, __FUNCTION__,
+ "zero-length directory entry");
+ err = -EIO;
+ goto out_unlock;
+ }
+ err = -EEXIST;
+ if (ufs_match(sb, namelen, name, de))
+ goto out_unlock;
+ name_len = UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de));
+ rec_len = fs16_to_cpu(sb, de->d_reclen);
+ if (!de->d_ino && rec_len >= reclen)
+ goto got_it;
+ if (rec_len >= name_len + reclen)
+ goto got_it;
+ de = (struct ufs_dir_entry *) ((char *) de + rec_len);
}
- if (!ufs_check_dir_entry ("ufs_add_entry", dir, de, bh, offset)) {
- brelse (bh);
- return -ENOENT;
- }
- if (ufs_match(sb, namelen, name, de)) {
- brelse (bh);
- return -EEXIST;
- }
- if (de->d_ino == 0 && fs16_to_cpu(sb, de->d_reclen) >= rec_len)
- break;
-
- if (fs16_to_cpu(sb, de->d_reclen) >=
- UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)) + rec_len)
- break;
- offset += fs16_to_cpu(sb, de->d_reclen);
- de = (struct ufs_dir_entry *) ((char *) de + fs16_to_cpu(sb, de->d_reclen));
+ unlock_page(page);
+ ufs_put_page(page);
}
+ BUG();
+ return -EINVAL;
+got_it:
+ from = (char*)de - (char*)page_address(page);
+ to = from + rec_len;
+ err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
+ if (err)
+ goto out_unlock;
if (de->d_ino) {
- de1 = (struct ufs_dir_entry *) ((char *) de +
- UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
- de1->d_reclen =
- cpu_to_fs16(sb, fs16_to_cpu(sb, de->d_reclen) -
- UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
- de->d_reclen =
- cpu_to_fs16(sb, UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
+ struct ufs_dir_entry *de1 =
+ (struct ufs_dir_entry *) ((char *) de + name_len);
+ de1->d_reclen = cpu_to_fs16(sb, rec_len - name_len);
+ de->d_reclen = cpu_to_fs16(sb, name_len);
+
de = de1;
}
- de->d_ino = 0;
+
ufs_set_de_namlen(sb, de, namelen);
- memcpy (de->d_name, name, namelen + 1);
+ memcpy(de->d_name, name, namelen + 1);
de->d_ino = cpu_to_fs32(sb, inode->i_ino);
ufs_set_de_type(sb, de, inode->i_mode);
- mark_buffer_dirty(bh);
- if (IS_DIRSYNC(dir))
- sync_dirty_buffer(bh);
- brelse (bh);
- dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
- dir->i_version++;
- mark_inode_dirty(dir);
- UFSD(("EXIT\n"))
+ err = ufs_commit_chunk(page, from, to);
+ dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
+
+ mark_inode_dirty(dir);
+ /* OFFSET_CACHE */
+out_put:
+ ufs_put_page(page);
+out:
+ return err;
+out_unlock:
+ unlock_page(page);
+ goto out_put;
+}
+
+static inline unsigned
+ufs_validate_entry(struct super_block *sb, char *base,
+ unsigned offset, unsigned mask)
+{
+ struct ufs_dir_entry *de = (struct ufs_dir_entry*)(base + offset);
+ struct ufs_dir_entry *p = (struct ufs_dir_entry*)(base + (offset&mask));
+ while ((char*)p < (char*)de) {
+ if (p->d_reclen == 0)
+ break;
+ p = ufs_next_entry(sb, p);
+ }
+ return (char *)p - base;
+}
+
+
+/*
+ * This is blatantly stolen from ext2fs
+ */
+static int
+ufs_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+ loff_t pos = filp->f_pos;
+ struct inode *inode = filp->f_dentry->d_inode;
+ struct super_block *sb = inode->i_sb;
+ unsigned int offset = pos & ~PAGE_CACHE_MASK;
+ unsigned long n = pos >> PAGE_CACHE_SHIFT;
+ unsigned long npages = ufs_dir_pages(inode);
+ unsigned chunk_mask = ~(UFS_SECTOR_SIZE - 1);
+ int need_revalidate = filp->f_version != inode->i_version;
+ unsigned flags = UFS_SB(sb)->s_flags;
+
+ UFSD(("BEGIN"));
+
+ if (pos > inode->i_size - UFS_DIR_REC_LEN(1))
+ return 0;
+
+ for ( ; n < npages; n++, offset = 0) {
+ char *kaddr, *limit;
+ struct ufs_dir_entry *de;
+
+ struct page *page = ufs_get_page(inode, n);
+
+ if (IS_ERR(page)) {
+ ufs_error(sb, __FUNCTION__,
+ "bad page in #%lu",
+ inode->i_ino);
+ filp->f_pos += PAGE_CACHE_SIZE - offset;
+ return -EIO;
+ }
+ kaddr = page_address(page);
+ if (unlikely(need_revalidate)) {
+ if (offset) {
+ offset = ufs_validate_entry(sb, kaddr, offset, chunk_mask);
+ filp->f_pos = (n<<PAGE_CACHE_SHIFT) + offset;
+ }
+ filp->f_version = inode->i_version;
+ need_revalidate = 0;
+ }
+ de = (struct ufs_dir_entry *)(kaddr+offset);
+ limit = kaddr + ufs_last_byte(inode, n) - UFS_DIR_REC_LEN(1);
+ for ( ;(char*)de <= limit; de = ufs_next_entry(sb, de)) {
+ if (de->d_reclen == 0) {
+ ufs_error(sb, __FUNCTION__,
+ "zero-length directory entry");
+ ufs_put_page(page);
+ return -EIO;
+ }
+ if (de->d_ino) {
+ int over;
+ unsigned char d_type = DT_UNKNOWN;
+
+ offset = (char *)de - kaddr;
+
+ UFSD(("filldir(%s,%u)\n", de->d_name,
+ fs32_to_cpu(sb, de->d_ino)));
+ UFSD(("namlen %u\n", ufs_get_de_namlen(sb, de)));
+
+ if ((flags & UFS_DE_MASK) == UFS_DE_44BSD)
+ d_type = de->d_u.d_44.d_type;
+
+ over = filldir(dirent, de->d_name,
+ ufs_get_de_namlen(sb, de),
+ (n<<PAGE_CACHE_SHIFT) | offset,
+ fs32_to_cpu(sb, de->d_ino), d_type);
+ if (over) {
+ ufs_put_page(page);
+ return 0;
+ }
+ }
+ filp->f_pos += fs16_to_cpu(sb, de->d_reclen);
+ }
+ ufs_put_page(page);
+ }
return 0;
}
+
/*
* ufs_delete_entry deletes a directory entry by merging it with the
* previous entry.
*/
-int ufs_delete_entry (struct inode * inode, struct ufs_dir_entry * dir,
- struct buffer_head * bh )
-
+int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir,
+ struct page * page)
{
- struct super_block * sb;
- struct ufs_dir_entry * de, * pde;
- unsigned i;
-
- UFSD(("ENTER\n"))
+ struct super_block *sb = inode->i_sb;
+ struct address_space *mapping = page->mapping;
+ char *kaddr = page_address(page);
+ unsigned from = ((char*)dir - kaddr) & ~(UFS_SECTOR_SIZE - 1);
+ unsigned to = ((char*)dir - kaddr) + fs16_to_cpu(sb, dir->d_reclen);
+ struct ufs_dir_entry *pde = NULL;
+ struct ufs_dir_entry *de = (struct ufs_dir_entry *) (kaddr + from);
+ int err;
- sb = inode->i_sb;
- i = 0;
- pde = NULL;
- de = (struct ufs_dir_entry *) bh->b_data;
-
+ UFSD(("ENTER\n"));
+
UFSD(("ino %u, reclen %u, namlen %u, name %s\n",
- fs32_to_cpu(sb, de->d_ino),
- fs16_to_cpu(sb, de->d_reclen),
- ufs_get_de_namlen(sb, de), de->d_name))
+ fs32_to_cpu(sb, de->d_ino),
+ fs16_to_cpu(sb, de->d_reclen),
+ ufs_get_de_namlen(sb, de), de->d_name));
- while (i < bh->b_size) {
- if (!ufs_check_dir_entry ("ufs_delete_entry", inode, de, bh, i)) {
- brelse(bh);
- return -EIO;
+ while ((char*)de < (char*)dir) {
+ if (de->d_reclen == 0) {
+ ufs_error(inode->i_sb, __FUNCTION__,
+ "zero-length directory entry");
+ err = -EIO;
+ goto out;
}
- if (de == dir) {
- if (pde)
- fs16_add(sb, &pde->d_reclen,
- fs16_to_cpu(sb, dir->d_reclen));
- dir->d_ino = 0;
- inode->i_version++;
- inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
- mark_inode_dirty(inode);
- mark_buffer_dirty(bh);
- if (IS_DIRSYNC(inode))
- sync_dirty_buffer(bh);
- brelse(bh);
- UFSD(("EXIT\n"))
- return 0;
- }
- i += fs16_to_cpu(sb, de->d_reclen);
- if (i == UFS_SECTOR_SIZE) pde = NULL;
- else pde = de;
- de = (struct ufs_dir_entry *)
- ((char *) de + fs16_to_cpu(sb, de->d_reclen));
- if (i == UFS_SECTOR_SIZE && de->d_reclen == 0)
- break;
+ pde = de;
+ de = ufs_next_entry(sb, de);
}
- UFSD(("EXIT\n"))
- brelse(bh);
- return -ENOENT;
+ if (pde)
+ from = (char*)pde - (char*)page_address(page);
+ lock_page(page);
+ err = mapping->a_ops->prepare_write(NULL, page, from, to);
+ BUG_ON(err);
+ if (pde)
+ pde->d_reclen = cpu_to_fs16(sb, to-from);
+ dir->d_ino = 0;
+ err = ufs_commit_chunk(page, from, to);
+ inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
+ mark_inode_dirty(inode);
+out:
+ ufs_put_page(page);
+ UFSD(("EXIT\n"));
+ return err;
}
int ufs_make_empty(struct inode * inode, struct inode *dir)
{
struct super_block * sb = dir->i_sb;
- struct buffer_head * dir_block;
+ struct address_space *mapping = inode->i_mapping;
+ struct page *page = grab_cache_page(mapping, 0);
struct ufs_dir_entry * de;
+ char *base;
int err;
- dir_block = ufs_bread (inode, 0, 1, &err);
- if (!dir_block)
- return err;
+ if (!page)
+ return -ENOMEM;
+ kmap(page);
+ err = mapping->a_ops->prepare_write(NULL, page, 0, UFS_SECTOR_SIZE);
+ if (err) {
+ unlock_page(page);
+ goto fail;
+ }
- inode->i_blocks = sb->s_blocksize / UFS_SECTOR_SIZE;
- de = (struct ufs_dir_entry *) dir_block->b_data;
+
+ base = (char*)page_address(page);
+ memset(base, 0, PAGE_CACHE_SIZE);
+
+ de = (struct ufs_dir_entry *) base;
+
de->d_ino = cpu_to_fs32(sb, inode->i_ino);
ufs_set_de_type(sb, de, inode->i_mode);
ufs_set_de_namlen(sb, de, 1);
@@ -552,72 +594,65 @@
de->d_reclen = cpu_to_fs16(sb, UFS_SECTOR_SIZE - UFS_DIR_REC_LEN(1));
ufs_set_de_namlen(sb, de, 2);
strcpy (de->d_name, "..");
- mark_buffer_dirty(dir_block);
- brelse (dir_block);
- mark_inode_dirty(inode);
- return 0;
+
+ err = ufs_commit_chunk(page, 0, UFS_SECTOR_SIZE);
+fail:
+ kunmap(page);
+ page_cache_release(page);
+ return err;
}
/*
* routine to check that the specified directory is empty (for rmdir)
*/
-int ufs_empty_dir (struct inode * inode)
+int ufs_empty_dir(struct inode * inode)
{
- struct super_block * sb;
- unsigned long offset;
- struct buffer_head * bh;
- struct ufs_dir_entry * de, * de1;
- int err;
-
- sb = inode->i_sb;
+ struct super_block *sb = inode->i_sb;
+ struct page *page = NULL;
+ unsigned long i, npages = ufs_dir_pages(inode);
- if (inode->i_size < UFS_DIR_REC_LEN(1) + UFS_DIR_REC_LEN(2) ||
- !(bh = ufs_bread (inode, 0, 0, &err))) {
- ufs_warning (inode->i_sb, "empty_dir",
- "bad directory (dir #%lu) - no data block",
- inode->i_ino);
- return 1;
- }
- de = (struct ufs_dir_entry *) bh->b_data;
- de1 = (struct ufs_dir_entry *)
- ((char *)de + fs16_to_cpu(sb, de->d_reclen));
- if (fs32_to_cpu(sb, de->d_ino) != inode->i_ino || de1->d_ino == 0 ||
- strcmp (".", de->d_name) || strcmp ("..", de1->d_name)) {
- ufs_warning (inode->i_sb, "empty_dir",
- "bad directory (dir #%lu) - no `.' or `..'",
- inode->i_ino);
- return 1;
- }
- offset = fs16_to_cpu(sb, de->d_reclen) + fs16_to_cpu(sb, de1->d_reclen);
- de = (struct ufs_dir_entry *)
- ((char *)de1 + fs16_to_cpu(sb, de1->d_reclen));
- while (offset < inode->i_size ) {
- if (!bh || (void *) de >= (void *) (bh->b_data + sb->s_blocksize)) {
- brelse (bh);
- bh = ufs_bread (inode, offset >> sb->s_blocksize_bits, 1, &err);
- if (!bh) {
- ufs_error (sb, "empty_dir",
- "directory #%lu contains a hole at offset %lu",
- inode->i_ino, offset);
- offset += sb->s_blocksize;
- continue;
+ for (i = 0; i < npages; i++) {
+ char *kaddr;
+ struct ufs_dir_entry *de;
+ page = ufs_get_page(inode, i);
+
+ if (IS_ERR(page))
+ continue;
+
+ kaddr = page_address(page);
+ de = (struct ufs_dir_entry *)kaddr;
+ kaddr += ufs_last_byte(inode, i) - UFS_DIR_REC_LEN(1);
+
+ while ((char *)de <= kaddr) {
+ if (de->d_reclen == 0) {
+ ufs_error(inode->i_sb, __FUNCTION__,
+ "zero-length directory entry: "
+ "kaddr=%p, de=%p\n", kaddr, de);
+ goto not_empty;
}
- de = (struct ufs_dir_entry *) bh->b_data;
+ if (de->d_ino) {
+ u16 namelen=ufs_get_de_namlen(sb, de);
+ /* check for . and .. */
+ if (de->d_name[0] != '.')
+ goto not_empty;
+ if (namelen > 2)
+ goto not_empty;
+ if (namelen < 2) {
+ if (inode->i_ino !=
+ fs32_to_cpu(sb, de->d_ino))
+ goto not_empty;
+ } else if (de->d_name[1] != '.')
+ goto not_empty;
+ }
+ de = ufs_next_entry(sb, de);
}
- if (!ufs_check_dir_entry ("empty_dir", inode, de, bh, offset)) {
- brelse (bh);
- return 1;
- }
- if (de->d_ino) {
- brelse (bh);
- return 0;
- }
- offset += fs16_to_cpu(sb, de->d_reclen);
- de = (struct ufs_dir_entry *)
- ((char *)de + fs16_to_cpu(sb, de->d_reclen));
+ ufs_put_page(page);
}
- brelse (bh);
return 1;
+
+not_empty:
+ ufs_put_page(page);
+ return 0;
}
const struct file_operations ufs_dir_operations = {