Re: [PATCH 03/17] ocfs2/dlm: replace __get_free_page() with kmalloc()

[Joseph Qi]

On 5/24/26 1:54 AM, Mike Rapoport (Microsoft) wrote:
> A few places in ocsfs2 allocate temporary buffers with __get_free_page() or
> get_zeroed_page().
> 
> kmalloc() is a better API for such use and it also provides better
> scalability and more debugging possibilities.
> 
> Replace use of __get_free_page() and get_zeroed_page() with kmalloc() and
> kzalloc() respectively.
> 
> Signed-off-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>

Looks fine.
Reviewed-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx>

> ---
>  fs/ocfs2/dlm/dlmdebug.c    | 24 +++++++++---------------
>  fs/ocfs2/dlm/dlmdomain.c   |  8 +++++---
>  fs/ocfs2/dlm/dlmmaster.c   |  5 ++---
>  fs/ocfs2/dlm/dlmrecovery.c |  4 ++--
>  4 files changed, 18 insertions(+), 23 deletions(-)
> 
> diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c
> index fe4fdd09bae3..6ca8b3b68eef 100644
> --- a/fs/ocfs2/dlm/dlmdebug.c
> +++ b/fs/ocfs2/dlm/dlmdebug.c
> @@ -260,10 +260,10 @@ void dlm_print_one_mle(struct dlm_master_list_entry *mle)
>  {
>  	char *buf;
>  
> -	buf = (char *) get_zeroed_page(GFP_ATOMIC);
> +	buf = kzalloc(PAGE_SIZE, GFP_ATOMIC);
>  	if (buf) {
>  		dump_mle(mle, buf, PAGE_SIZE - 1);
> -		free_page((unsigned long)buf);
> +		kfree(buf);
>  	}
>  }
>  
> @@ -280,7 +280,7 @@ static struct dentry *dlm_debugfs_root;
>  /* begin - utils funcs */
>  static int debug_release(struct inode *inode, struct file *file)
>  {
> -	free_page((unsigned long)file->private_data);
> +	kfree(file->private_data);
>  	return 0;
>  }
>  
> @@ -327,17 +327,15 @@ static int debug_purgelist_open(struct inode *inode, struct file *file)
>  	struct dlm_ctxt *dlm = inode->i_private;
>  	char *buf = NULL;
>  
> -	buf = (char *) get_zeroed_page(GFP_NOFS);
> +	buf = kzalloc(PAGE_SIZE, GFP_NOFS);
>  	if (!buf)
> -		goto bail;
> +		return -ENOMEM;
>  
>  	i_size_write(inode, debug_purgelist_print(dlm, buf, PAGE_SIZE - 1));
>  
>  	file->private_data = buf;
>  
>  	return 0;
> -bail:
> -	return -ENOMEM;
>  }
>  
>  static const struct file_operations debug_purgelist_fops = {
> @@ -384,17 +382,15 @@ static int debug_mle_open(struct inode *inode, struct file *file)
>  	struct dlm_ctxt *dlm = inode->i_private;
>  	char *buf = NULL;
>  
> -	buf = (char *) get_zeroed_page(GFP_NOFS);
> +	buf = kzalloc(PAGE_SIZE, GFP_NOFS);
>  	if (!buf)
> -		goto bail;
> +		return -ENOMEM;
>  
>  	i_size_write(inode, debug_mle_print(dlm, buf, PAGE_SIZE - 1));
>  
>  	file->private_data = buf;
>  
>  	return 0;
> -bail:
> -	return -ENOMEM;
>  }
>  
>  static const struct file_operations debug_mle_fops = {
> @@ -775,17 +771,15 @@ static int debug_state_open(struct inode *inode, struct file *file)
>  	struct dlm_ctxt *dlm = inode->i_private;
>  	char *buf = NULL;
>  
> -	buf = (char *) get_zeroed_page(GFP_NOFS);
> +	buf = kzalloc(PAGE_SIZE, GFP_NOFS);
>  	if (!buf)
> -		goto bail;
> +		return -ENOMEM;
>  
>  	i_size_write(inode, debug_state_print(dlm, buf, PAGE_SIZE - 1));
>  
>  	file->private_data = buf;
>  
>  	return 0;
> -bail:
> -	return -ENOMEM;
>  }
>  
>  static const struct file_operations debug_state_fops = {
> diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
> index dc9da9133c8e..97bb9400e24b 100644
> --- a/fs/ocfs2/dlm/dlmdomain.c
> +++ b/fs/ocfs2/dlm/dlmdomain.c
> @@ -63,7 +63,7 @@ static inline void byte_copymap(u8 dmap[], unsigned long smap[],
>  static void dlm_free_pagevec(void **vec, int pages)
>  {
>  	while (pages--)
> -		free_page((unsigned long)vec[pages]);
> +		kfree(vec[pages]);
>  	kfree(vec);
>  }
>  
> @@ -75,9 +75,11 @@ static void **dlm_alloc_pagevec(int pages)
>  	if (!vec)
>  		return NULL;
>  
> -	for (i = 0; i < pages; i++)
> -		if (!(vec[i] = (void *)__get_free_page(GFP_KERNEL)))
> +	for (i = 0; i < pages; i++) {
> +		vec[i] = kmalloc(PAGE_SIZE, GFP_KERNEL);
> +		if (!vec[i])
>  			goto out_free;
> +	}
>  
>  	mlog(0, "Allocated DLM hash pagevec; %d pages (%lu expected), %lu buckets per page\n",
>  	     pages, (unsigned long)DLM_HASH_PAGES,
> diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
> index 93eff38fdadd..aee3b4c56dcc 100644
> --- a/fs/ocfs2/dlm/dlmmaster.c
> +++ b/fs/ocfs2/dlm/dlmmaster.c
> @@ -2548,7 +2548,7 @@ static int dlm_migrate_lockres(struct dlm_ctxt *dlm,
>  
>  	/* preallocate up front. if this fails, abort */
>  	ret = -ENOMEM;
> -	mres = (struct dlm_migratable_lockres *) __get_free_page(GFP_NOFS);
> +	mres = kmalloc(PAGE_SIZE, GFP_NOFS);
>  	if (!mres) {
>  		mlog_errno(ret);
>  		goto leave;
> @@ -2725,8 +2725,7 @@ static int dlm_migrate_lockres(struct dlm_ctxt *dlm,
>  	if (wake)
>  		wake_up(&res->wq);
>  
> -	if (mres)
> -		free_page((unsigned long)mres);
> +	kfree(mres);
>  
>  	dlm_put(dlm);
>  
> diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c
> index 128872bd945d..9b97bf73df22 100644
> --- a/fs/ocfs2/dlm/dlmrecovery.c
> +++ b/fs/ocfs2/dlm/dlmrecovery.c
> @@ -837,7 +837,7 @@ int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
>  	}
>  
>  	/* this will get freed by dlm_request_all_locks_worker */
> -	buf = (char *) __get_free_page(GFP_NOFS);
> +	buf = kmalloc(PAGE_SIZE, GFP_NOFS);
>  	if (!buf) {
>  		kfree(item);
>  		dlm_put(dlm);
> @@ -933,7 +933,7 @@ static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data)
>  		}
>  	}
>  leave:
> -	free_page((unsigned long)data);
> +	kfree(data);
>  }
>  
>  
>