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-rw-r--r--fs/sysv/dir.c154
-rw-r--r--fs/sysv/namei.c42
-rw-r--r--fs/sysv/sysv.h3
3 files changed, 111 insertions, 88 deletions
diff --git a/fs/sysv/dir.c b/fs/sysv/dir.c
index 88e38cd8f5c9..999bceb99974 100644
--- a/fs/sysv/dir.c
+++ b/fs/sysv/dir.c
@@ -28,37 +28,50 @@ const struct file_operations sysv_dir_operations = {
.fsync = generic_file_fsync,
};
-static inline void dir_put_page(struct page *page)
+inline void dir_put_page(struct page *page, void *page_addr)
{
- kunmap(page);
+ kunmap_local((void *)((unsigned long)page_addr & PAGE_MASK));
put_page(page);
}
-static int dir_commit_chunk(struct page *page, loff_t pos, unsigned len)
+static void dir_commit_chunk(struct page *page, loff_t pos, unsigned len)
{
struct address_space *mapping = page->mapping;
struct inode *dir = mapping->host;
- int err = 0;
block_write_end(NULL, mapping, pos, len, len, page, NULL);
if (pos+len > dir->i_size) {
i_size_write(dir, pos+len);
mark_inode_dirty(dir);
}
- if (IS_DIRSYNC(dir))
- err = write_one_page(page);
- else
- unlock_page(page);
+ unlock_page(page);
+}
+
+static int sysv_handle_dirsync(struct inode *dir)
+{
+ int err;
+
+ err = filemap_write_and_wait(dir->i_mapping);
+ if (!err)
+ err = sync_inode_metadata(dir, 1);
return err;
}
-static struct page * dir_get_page(struct inode *dir, unsigned long n)
+/*
+ * Calls to dir_get_page()/dir_put_page() must be nested according to the
+ * rules documented in mm/highmem.rst.
+ *
+ * NOTE: sysv_find_entry() and sysv_dotdot() act as calls to dir_get_page()
+ * and must be treated accordingly for nesting purposes.
+ */
+static void *dir_get_page(struct inode *dir, unsigned long n, struct page **p)
{
struct address_space *mapping = dir->i_mapping;
struct page *page = read_mapping_page(mapping, n, NULL);
- if (!IS_ERR(page))
- kmap(page);
- return page;
+ if (IS_ERR(page))
+ return ERR_CAST(page);
+ *p = page;
+ return kmap_local_page(page);
}
static int sysv_readdir(struct file *file, struct dir_context *ctx)
@@ -80,11 +93,11 @@ static int sysv_readdir(struct file *file, struct dir_context *ctx)
for ( ; n < npages; n++, offset = 0) {
char *kaddr, *limit;
struct sysv_dir_entry *de;
- struct page *page = dir_get_page(inode, n);
+ struct page *page;
- if (IS_ERR(page))
+ kaddr = dir_get_page(inode, n, &page);
+ if (IS_ERR(kaddr))
continue;
- kaddr = (char *)page_address(page);
de = (struct sysv_dir_entry *)(kaddr+offset);
limit = kaddr + PAGE_SIZE - SYSV_DIRSIZE;
for ( ;(char*)de <= limit; de++, ctx->pos += sizeof(*de)) {
@@ -96,11 +109,11 @@ static int sysv_readdir(struct file *file, struct dir_context *ctx)
if (!dir_emit(ctx, name, strnlen(name,SYSV_NAMELEN),
fs16_to_cpu(SYSV_SB(sb), de->inode),
DT_UNKNOWN)) {
- dir_put_page(page);
+ dir_put_page(page, kaddr);
return 0;
}
}
- dir_put_page(page);
+ dir_put_page(page, kaddr);
}
return 0;
}
@@ -123,6 +136,11 @@ static inline int namecompare(int len, int maxlen,
* 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.
+ *
+ * On Success dir_put_page() should be called on *res_page.
+ *
+ * sysv_find_entry() acts as a call to dir_get_page() and must be treated
+ * accordingly for nesting purposes.
*/
struct sysv_dir_entry *sysv_find_entry(struct dentry *dentry, struct page **res_page)
{
@@ -142,11 +160,10 @@ struct sysv_dir_entry *sysv_find_entry(struct dentry *dentry, struct page **res_
n = start;
do {
- char *kaddr;
- page = dir_get_page(dir, n);
- if (!IS_ERR(page)) {
- kaddr = (char*)page_address(page);
- de = (struct sysv_dir_entry *) kaddr;
+ char *kaddr = dir_get_page(dir, n, &page);
+
+ if (!IS_ERR(kaddr)) {
+ de = (struct sysv_dir_entry *)kaddr;
kaddr += PAGE_SIZE - SYSV_DIRSIZE;
for ( ; (char *) de <= kaddr ; de++) {
if (!de->inode)
@@ -155,7 +172,7 @@ struct sysv_dir_entry *sysv_find_entry(struct dentry *dentry, struct page **res_
name, de->name))
goto found;
}
- dir_put_page(page);
+ dir_put_page(page, kaddr);
}
if (++n >= npages)
@@ -185,11 +202,9 @@ int sysv_add_link(struct dentry *dentry, struct inode *inode)
/* We take care of directory expansion in the same loop */
for (n = 0; n <= npages; n++) {
- page = dir_get_page(dir, n);
- err = PTR_ERR(page);
- if (IS_ERR(page))
- goto out;
- kaddr = (char*)page_address(page);
+ kaddr = dir_get_page(dir, n, &page);
+ if (IS_ERR(kaddr))
+ return PTR_ERR(kaddr);
de = (struct sysv_dir_entry *)kaddr;
kaddr += PAGE_SIZE - SYSV_DIRSIZE;
while ((char *)de <= kaddr) {
@@ -200,14 +215,13 @@ int sysv_add_link(struct dentry *dentry, struct inode *inode)
goto out_page;
de++;
}
- dir_put_page(page);
+ dir_put_page(page, kaddr);
}
BUG();
return -EINVAL;
got_it:
- pos = page_offset(page) +
- (char*)de - (char*)page_address(page);
+ pos = page_offset(page) + offset_in_page(de);
lock_page(page);
err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
if (err)
@@ -215,12 +229,12 @@ got_it:
memcpy (de->name, name, namelen);
memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2);
de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
- err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
+ dir_commit_chunk(page, pos, SYSV_DIRSIZE);
dir->i_mtime = dir->i_ctime = current_time(dir);
mark_inode_dirty(dir);
+ err = sysv_handle_dirsync(dir);
out_page:
- dir_put_page(page);
-out:
+ dir_put_page(page, kaddr);
return err;
out_unlock:
unlock_page(page);
@@ -230,19 +244,20 @@ out_unlock:
int sysv_delete_entry(struct sysv_dir_entry *de, struct page *page)
{
struct inode *inode = page->mapping->host;
- char *kaddr = (char*)page_address(page);
- loff_t pos = page_offset(page) + (char *)de - kaddr;
+ loff_t pos = page_offset(page) + offset_in_page(de);
int err;
lock_page(page);
err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
- BUG_ON(err);
+ if (err) {
+ unlock_page(page);
+ return err;
+ }
de->inode = 0;
- err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
- dir_put_page(page);
+ dir_commit_chunk(page, pos, SYSV_DIRSIZE);
inode->i_ctime = inode->i_mtime = current_time(inode);
mark_inode_dirty(inode);
- return err;
+ return sysv_handle_dirsync(inode);
}
int sysv_make_empty(struct inode *inode, struct inode *dir)
@@ -259,9 +274,7 @@ int sysv_make_empty(struct inode *inode, struct inode *dir)
unlock_page(page);
goto fail;
}
- kmap(page);
-
- base = (char*)page_address(page);
+ base = kmap_local_page(page);
memset(base, 0, PAGE_SIZE);
de = (struct sysv_dir_entry *) base;
@@ -271,8 +284,9 @@ int sysv_make_empty(struct inode *inode, struct inode *dir)
de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), dir->i_ino);
strcpy(de->name,"..");
- kunmap(page);
- err = dir_commit_chunk(page, 0, 2 * SYSV_DIRSIZE);
+ kunmap_local(base);
+ dir_commit_chunk(page, 0, 2 * SYSV_DIRSIZE);
+ err = sysv_handle_dirsync(inode);
fail:
put_page(page);
return err;
@@ -286,16 +300,15 @@ int sysv_empty_dir(struct inode * inode)
struct super_block *sb = inode->i_sb;
struct page *page = NULL;
unsigned long i, npages = dir_pages(inode);
+ char *kaddr;
for (i = 0; i < npages; i++) {
- char *kaddr;
- struct sysv_dir_entry * de;
- page = dir_get_page(inode, i);
+ struct sysv_dir_entry *de;
- if (IS_ERR(page))
+ kaddr = dir_get_page(inode, i, &page);
+ if (IS_ERR(kaddr))
continue;
- kaddr = (char *)page_address(page);
de = (struct sysv_dir_entry *)kaddr;
kaddr += PAGE_SIZE-SYSV_DIRSIZE;
@@ -314,44 +327,51 @@ int sysv_empty_dir(struct inode * inode)
if (de->name[1] != '.' || de->name[2])
goto not_empty;
}
- dir_put_page(page);
+ dir_put_page(page, kaddr);
}
return 1;
not_empty:
- dir_put_page(page);
+ dir_put_page(page, kaddr);
return 0;
}
/* Releases the page */
-void sysv_set_link(struct sysv_dir_entry *de, struct page *page,
+int sysv_set_link(struct sysv_dir_entry *de, struct page *page,
struct inode *inode)
{
struct inode *dir = page->mapping->host;
- loff_t pos = page_offset(page) +
- (char *)de-(char*)page_address(page);
+ loff_t pos = page_offset(page) + offset_in_page(de);
int err;
lock_page(page);
err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
- BUG_ON(err);
+ if (err) {
+ unlock_page(page);
+ return err;
+ }
de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
- err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
- dir_put_page(page);
+ dir_commit_chunk(page, pos, SYSV_DIRSIZE);
dir->i_mtime = dir->i_ctime = current_time(dir);
mark_inode_dirty(dir);
+ return sysv_handle_dirsync(inode);
}
-struct sysv_dir_entry * sysv_dotdot (struct inode *dir, struct page **p)
+/*
+ * Calls to dir_get_page()/dir_put_page() must be nested according to the
+ * rules documented in mm/highmem.rst.
+ *
+ * sysv_dotdot() acts as a call to dir_get_page() and must be treated
+ * accordingly for nesting purposes.
+ */
+struct sysv_dir_entry *sysv_dotdot(struct inode *dir, struct page **p)
{
- struct page *page = dir_get_page(dir, 0);
- struct sysv_dir_entry *de = NULL;
+ struct sysv_dir_entry *de = dir_get_page(dir, 0, p);
- if (!IS_ERR(page)) {
- de = (struct sysv_dir_entry*) page_address(page) + 1;
- *p = page;
- }
- return de;
+ if (IS_ERR(de))
+ return NULL;
+ /* ".." is the second directory entry */
+ return de + 1;
}
ino_t sysv_inode_by_name(struct dentry *dentry)
@@ -362,7 +382,7 @@ ino_t sysv_inode_by_name(struct dentry *dentry)
if (de) {
res = fs16_to_cpu(SYSV_SB(dentry->d_sb), de->inode);
- dir_put_page(page);
+ dir_put_page(page, de);
}
return res;
}
diff --git a/fs/sysv/namei.c b/fs/sysv/namei.c
index ecd424461511..a25862773d82 100644
--- a/fs/sysv/namei.c
+++ b/fs/sysv/namei.c
@@ -153,19 +153,18 @@ static int sysv_unlink(struct inode * dir, struct dentry * dentry)
struct inode * inode = d_inode(dentry);
struct page * page;
struct sysv_dir_entry * de;
- int err = -ENOENT;
+ int err;
de = sysv_find_entry(dentry, &page);
if (!de)
- goto out;
+ return -ENOENT;
- err = sysv_delete_entry (de, page);
- if (err)
- goto out;
-
- inode->i_ctime = dir->i_ctime;
- inode_dec_link_count(inode);
-out:
+ err = sysv_delete_entry(de, page);
+ if (!err) {
+ inode->i_ctime = dir->i_ctime;
+ inode_dec_link_count(inode);
+ }
+ dir_put_page(page, de);
return err;
}
@@ -227,7 +226,10 @@ static int sysv_rename(struct mnt_idmap *idmap, struct inode *old_dir,
new_de = sysv_find_entry(new_dentry, &new_page);
if (!new_de)
goto out_dir;
- sysv_set_link(new_de, new_page, old_inode);
+ err = sysv_set_link(new_de, new_page, old_inode);
+ dir_put_page(new_page, new_de);
+ if (err)
+ goto out_dir;
new_inode->i_ctime = current_time(new_inode);
if (dir_de)
drop_nlink(new_inode);
@@ -240,23 +242,23 @@ static int sysv_rename(struct mnt_idmap *idmap, struct inode *old_dir,
inode_inc_link_count(new_dir);
}
- sysv_delete_entry(old_de, old_page);
+ err = sysv_delete_entry(old_de, old_page);
+ if (err)
+ goto out_dir;
+
mark_inode_dirty(old_inode);
if (dir_de) {
- sysv_set_link(dir_de, dir_page, new_dir);
- inode_dec_link_count(old_dir);
+ err = sysv_set_link(dir_de, dir_page, new_dir);
+ if (!err)
+ inode_dec_link_count(old_dir);
}
- return 0;
out_dir:
- if (dir_de) {
- kunmap(dir_page);
- put_page(dir_page);
- }
+ if (dir_de)
+ dir_put_page(dir_page, dir_de);
out_old:
- kunmap(old_page);
- put_page(old_page);
+ dir_put_page(old_page, old_de);
out:
return err;
}
diff --git a/fs/sysv/sysv.h b/fs/sysv/sysv.h
index 5e122a5673c1..f2c36ea42df6 100644
--- a/fs/sysv/sysv.h
+++ b/fs/sysv/sysv.h
@@ -148,12 +148,13 @@ extern void sysv_destroy_icache(void);
/* dir.c */
+extern void dir_put_page(struct page *page, void *vaddr);
extern struct sysv_dir_entry *sysv_find_entry(struct dentry *, struct page **);
extern int sysv_add_link(struct dentry *, struct inode *);
extern int sysv_delete_entry(struct sysv_dir_entry *, struct page *);
extern int sysv_make_empty(struct inode *, struct inode *);
extern int sysv_empty_dir(struct inode *);
-extern void sysv_set_link(struct sysv_dir_entry *, struct page *,
+extern int sysv_set_link(struct sysv_dir_entry *, struct page *,
struct inode *);
extern struct sysv_dir_entry *sysv_dotdot(struct inode *, struct page **);
extern ino_t sysv_inode_by_name(struct dentry *);
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-25 09:27:20 +0000