erofs: use meta buffers for inode operations

Get rid of old erofs_get_meta_page() within inode operations by
using on-stack meta buffers in order to prepare subpage and folio
features.

Link: https://lore.kernel.org/r/20220102040017.51352-3-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@yulong.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 2345f1de438e628fdee75abf23715b8dcc3c549e..ff62f84f47d30f9369fbeb01d9e7f7ce26223e60 100644 (file)
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -13,8 +13,8 @@
  * the inode payload page if it's an extended inode) in order to fill
  * inline data if possible.
  */
-static struct page *erofs_read_inode(struct inode *inode,
-                                    unsigned int *ofs)
+static void *erofs_read_inode(struct erofs_buf *buf,
+                             struct inode *inode, unsigned int *ofs)
 {
        struct super_block *sb = inode->i_sb;
        struct erofs_sb_info *sbi = EROFS_SB(sb);
@@ -22,7 +22,7 @@ static struct page *erofs_read_inode(struct inode *inode,
        const erofs_off_t inode_loc = iloc(sbi, vi->nid);
 
        erofs_blk_t blkaddr, nblks = 0;
-       struct page *page;
+       void *kaddr;
        struct erofs_inode_compact *dic;
        struct erofs_inode_extended *die, *copied = NULL;
        unsigned int ifmt;
@@ -34,14 +34,14 @@ static struct page *erofs_read_inode(struct inode *inode,
        erofs_dbg("%s, reading inode nid %llu at %u of blkaddr %u",
                  __func__, vi->nid, *ofs, blkaddr);
 
-       page = erofs_get_meta_page(sb, blkaddr);
-       if (IS_ERR(page)) {
+       kaddr = erofs_read_metabuf(buf, sb, blkaddr, EROFS_KMAP);
+       if (IS_ERR(kaddr)) {
                erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld",
-                         vi->nid, PTR_ERR(page));
-               return page;
+                         vi->nid, PTR_ERR(kaddr));
+               return kaddr;
        }
 
-       dic = page_address(page) + *ofs;
+       dic = kaddr + *ofs;
        ifmt = le16_to_cpu(dic->i_format);
 
        if (ifmt & ~EROFS_I_ALL) {
@@ -62,12 +62,12 @@ static struct page *erofs_read_inode(struct inode *inode,
        switch (erofs_inode_version(ifmt)) {
        case EROFS_INODE_LAYOUT_EXTENDED:
                vi->inode_isize = sizeof(struct erofs_inode_extended);
-               /* check if the inode acrosses page boundary */
-               if (*ofs + vi->inode_isize <= PAGE_SIZE) {
+               /* check if the extended inode acrosses block boundary */
+               if (*ofs + vi->inode_isize <= EROFS_BLKSIZ) {
                        *ofs += vi->inode_isize;
                        die = (struct erofs_inode_extended *)dic;
                } else {
-                       const unsigned int gotten = PAGE_SIZE - *ofs;
+                       const unsigned int gotten = EROFS_BLKSIZ - *ofs;
 
                        copied = kmalloc(vi->inode_isize, GFP_NOFS);
                        if (!copied) {
@@ -75,18 +75,16 @@ static struct page *erofs_read_inode(struct inode *inode,
                                goto err_out;
                        }
                        memcpy(copied, dic, gotten);
-                       unlock_page(page);
-                       put_page(page);
-
-                       page = erofs_get_meta_page(sb, blkaddr + 1);
-                       if (IS_ERR(page)) {
-                               erofs_err(sb, "failed to get inode payload page (nid: %llu), err %ld",
-                                         vi->nid, PTR_ERR(page));
+                       kaddr = erofs_read_metabuf(buf, sb, blkaddr + 1,
+                                                  EROFS_KMAP);
+                       if (IS_ERR(kaddr)) {
+                               erofs_err(sb, "failed to get inode payload block (nid: %llu), err %ld",
+                                         vi->nid, PTR_ERR(kaddr));
                                kfree(copied);
-                               return page;
+                               return kaddr;
                        }
                        *ofs = vi->inode_isize - gotten;
-                       memcpy((u8 *)copied + gotten, page_address(page), *ofs);
+                       memcpy((u8 *)copied + gotten, kaddr, *ofs);
                        die = copied;
                }
                vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount);
@@ -200,7 +198,7 @@ static struct page *erofs_read_inode(struct inode *inode,
                inode->i_blocks = roundup(inode->i_size, EROFS_BLKSIZ) >> 9;
        else
                inode->i_blocks = nblks << LOG_SECTORS_PER_BLOCK;
-       return page;
+       return kaddr;
 
 bogusimode:
        erofs_err(inode->i_sb, "bogus i_mode (%o) @ nid %llu",
@@ -209,12 +207,11 @@ bogusimode:
 err_out:
        DBG_BUGON(1);
        kfree(copied);
-       unlock_page(page);
-       put_page(page);
+       erofs_put_metabuf(buf);
        return ERR_PTR(err);
 }
 
-static int erofs_fill_symlink(struct inode *inode, void *data,
+static int erofs_fill_symlink(struct inode *inode, void *kaddr,
                              unsigned int m_pofs)
 {
        struct erofs_inode *vi = EROFS_I(inode);
@@ -222,7 +219,7 @@ static int erofs_fill_symlink(struct inode *inode, void *data,
 
        /* if it cannot be handled with fast symlink scheme */
        if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
-           inode->i_size >= PAGE_SIZE) {
+           inode->i_size >= EROFS_BLKSIZ) {
                inode->i_op = &erofs_symlink_iops;
                return 0;
        }
@@ -232,8 +229,8 @@ static int erofs_fill_symlink(struct inode *inode, void *data,
                return -ENOMEM;
 
        m_pofs += vi->xattr_isize;
-       /* inline symlink data shouldn't cross page boundary as well */
-       if (m_pofs + inode->i_size > PAGE_SIZE) {
+       /* inline symlink data shouldn't cross block boundary */
+       if (m_pofs + inode->i_size > EROFS_BLKSIZ) {
                kfree(lnk);
                erofs_err(inode->i_sb,
                          "inline data cross block boundary @ nid %llu",
@@ -241,8 +238,7 @@ static int erofs_fill_symlink(struct inode *inode, void *data,
                DBG_BUGON(1);
                return -EFSCORRUPTED;
        }
-
-       memcpy(lnk, data + m_pofs, inode->i_size);
+       memcpy(lnk, kaddr + m_pofs, inode->i_size);
        lnk[inode->i_size] = '\0';
 
        inode->i_link = lnk;
@@ -253,16 +249,17 @@ static int erofs_fill_symlink(struct inode *inode, void *data,
 static int erofs_fill_inode(struct inode *inode, int isdir)
 {
        struct erofs_inode *vi = EROFS_I(inode);
-       struct page *page;
+       struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
+       void *kaddr;
        unsigned int ofs;
        int err = 0;
 
        trace_erofs_fill_inode(inode, isdir);
 
        /* read inode base data from disk */
-       page = erofs_read_inode(inode, &ofs);
-       if (IS_ERR(page))
-               return PTR_ERR(page);
+       kaddr = erofs_read_inode(&buf, inode, &ofs);
+       if (IS_ERR(kaddr))
+               return PTR_ERR(kaddr);
 
        /* setup the new inode */
        switch (inode->i_mode & S_IFMT) {
@@ -278,7 +275,7 @@ static int erofs_fill_inode(struct inode *inode, int isdir)
                inode->i_fop = &erofs_dir_fops;
                break;
        case S_IFLNK:
-               err = erofs_fill_symlink(inode, page_address(page), ofs);
+               err = erofs_fill_symlink(inode, kaddr, ofs);
                if (err)
                        goto out_unlock;
                inode_nohighmem(inode);
@@ -302,8 +299,7 @@ static int erofs_fill_inode(struct inode *inode, int isdir)
        inode->i_mapping->a_ops = &erofs_raw_access_aops;
 
 out_unlock:
-       unlock_page(page);
-       put_page(page);
+       erofs_put_metabuf(&buf);
        return err;
 }
 

diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 7053f1c4171dea68818dbc380ad32abdb3c070d2..f1e4eb3025f6ddfa144003026dd5331d2682a078 100644 (file)
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -475,6 +475,9 @@ struct erofs_map_dev {
 /* data.c */
 extern const struct file_operations erofs_file_fops;
 struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr);
+void erofs_put_metabuf(struct erofs_buf *buf);
+void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
+                        erofs_blk_t blkaddr, enum erofs_kmap_type type);
 int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev);
 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
                 u64 start, u64 len);