From 287440c90e8bf967622072c0766d1c680d3c16ae Mon Sep 17 00:00:00 2001 From: Neil Brown Date: Sun, 12 Aug 2007 01:09:29 +0200 Subject: [PATCH] md/bitmap: tidy up i_writecount handling in md/bitmap md/bitmap modifies i_writecount of a bitmap file to make sure that no-one else writes to it. The reverting of the change is sometimes done twice, and there is one error path where it is omitted. This patch tidies that up. Signed-off-by: Neil Brown Signed-off-by: Adrian Bunk --- drivers/md/bitmap.c | 8 +------- drivers/md/md.c | 49 +++++++++++++++++++++++++++------------------ 2 files changed, 31 insertions(+), 26 deletions(-) diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index bd345d34d53f..2150693145fc 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -641,7 +641,6 @@ static void drain_write_queues(struct bitmap *bitmap) static void bitmap_file_put(struct bitmap *bitmap) { struct file *file; - struct inode *inode; unsigned long flags; spin_lock_irqsave(&bitmap->lock, flags); @@ -655,13 +654,8 @@ static void bitmap_file_put(struct bitmap *bitmap) bitmap_file_unmap(bitmap); - if (file) { - inode = file->f_mapping->host; - spin_lock(&inode->i_lock); - atomic_set(&inode->i_writecount, 1); /* allow writes again */ - spin_unlock(&inode->i_lock); + if (file) fput(file); - } } diff --git a/drivers/md/md.c b/drivers/md/md.c index 0d26b39e8a13..22ca22c343c6 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2644,6 +2644,32 @@ out: return err; } +/* similar to deny_write_access, but accounts for our holding a reference + * to the file ourselves */ +static int deny_bitmap_write_access(struct file * file) +{ + struct inode *inode = file->f_mapping->host; + + spin_lock(&inode->i_lock); + if (atomic_read(&inode->i_writecount) > 1) { + spin_unlock(&inode->i_lock); + return -ETXTBSY; + } + atomic_set(&inode->i_writecount, -1); + spin_unlock(&inode->i_lock); + + return 0; +} + +static void restore_bitmap_write_access(struct file *file) +{ + struct inode *inode = file->f_mapping->host; + + spin_lock(&inode->i_lock); + atomic_set(&inode->i_writecount, 1); + spin_unlock(&inode->i_lock); +} + static int do_md_stop(mddev_t * mddev, int ro) { int err = 0; @@ -2705,7 +2731,7 @@ static int do_md_stop(mddev_t * mddev, int ro) bitmap_destroy(mddev); if (mddev->bitmap_file) { - atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1); + restore_bitmap_write_access(mddev->bitmap_file); fput(mddev->bitmap_file); mddev->bitmap_file = NULL; } @@ -3299,23 +3325,6 @@ abort_export: return err; } -/* similar to deny_write_access, but accounts for our holding a reference - * to the file ourselves */ -static int deny_bitmap_write_access(struct file * file) -{ - struct inode *inode = file->f_mapping->host; - - spin_lock(&inode->i_lock); - if (atomic_read(&inode->i_writecount) > 1) { - spin_unlock(&inode->i_lock); - return -ETXTBSY; - } - atomic_set(&inode->i_writecount, -1); - spin_unlock(&inode->i_lock); - - return 0; -} - static int set_bitmap_file(mddev_t *mddev, int fd) { int err; @@ -3363,8 +3372,10 @@ static int set_bitmap_file(mddev_t *mddev, int fd) mddev->pers->quiesce(mddev, 0); } if (fd < 0) { - if (mddev->bitmap_file) + if (mddev->bitmap_file) { + restore_bitmap_write_access(mddev->bitmap_file); fput(mddev->bitmap_file); + } mddev->bitmap_file = NULL; } -- 2.39.5