use guard(mutex) for scope based resource management of mutex. This would make the code simpler and easier to maintain.
More details on lock guards can be found at https://lore.kernel.org/all/20230612093537.614161...@infradead.org/T/#u Signed-off-by: Shrikanth Hegde <sshe...@linux.ibm.com> --- arch/powerpc/kernel/rtas_flash.c | 64 ++++++++++---------------------- 1 file changed, 20 insertions(+), 44 deletions(-) diff --git a/arch/powerpc/kernel/rtas_flash.c b/arch/powerpc/kernel/rtas_flash.c index 5407024881e5..583dc16e9d3c 100644 --- a/arch/powerpc/kernel/rtas_flash.c +++ b/arch/powerpc/kernel/rtas_flash.c @@ -312,13 +312,13 @@ static ssize_t rtas_flash_write(struct file *file, const char __user *buffer, { struct rtas_update_flash_t *const uf = &rtas_update_flash_data; char *p; - int next_free, rc; + int next_free; struct flash_block_list *fl; - mutex_lock(&rtas_update_flash_mutex); + guard(mutex)(&rtas_update_flash_mutex); if (uf->status == FLASH_AUTH || count == 0) - goto out; /* discard data */ + return count; /* discard data */ /* In the case that the image is not ready for flashing, the memory * allocated for the block list will be freed upon the release of the @@ -327,7 +327,7 @@ static ssize_t rtas_flash_write(struct file *file, const char __user *buffer, if (uf->flist == NULL) { uf->flist = kmem_cache_zalloc(flash_block_cache, GFP_KERNEL); if (!uf->flist) - goto nomem; + return -ENOMEM; } fl = uf->flist; @@ -338,7 +338,7 @@ static ssize_t rtas_flash_write(struct file *file, const char __user *buffer, /* Need to allocate another block_list */ fl->next = kmem_cache_zalloc(flash_block_cache, GFP_KERNEL); if (!fl->next) - goto nomem; + return -ENOMEM; fl = fl->next; next_free = 0; } @@ -347,25 +347,17 @@ static ssize_t rtas_flash_write(struct file *file, const char __user *buffer, count = RTAS_BLK_SIZE; p = kmem_cache_zalloc(flash_block_cache, GFP_KERNEL); if (!p) - goto nomem; + return -ENOMEM; if(copy_from_user(p, buffer, count)) { kmem_cache_free(flash_block_cache, p); - rc = -EFAULT; - goto error; + return -EFAULT; } fl->blocks[next_free].data = p; fl->blocks[next_free].length = count; fl->num_blocks++; -out: - mutex_unlock(&rtas_update_flash_mutex); - return count; -nomem: - rc = -ENOMEM; -error: - mutex_unlock(&rtas_update_flash_mutex); - return rc; + return count; } /* @@ -405,19 +397,18 @@ static ssize_t manage_flash_write(struct file *file, const char __user *buf, static const char reject_str[] = "0"; static const char commit_str[] = "1"; char stkbuf[10]; - int op, rc; + int op; - mutex_lock(&rtas_manage_flash_mutex); + guard(mutex)(&rtas_manage_flash_mutex); if ((args_buf->status == MANAGE_AUTH) || (count == 0)) - goto out; + return count; op = -1; if (buf) { if (count > 9) count = 9; - rc = -EFAULT; if (copy_from_user (stkbuf, buf, count)) - goto error; + return -EFAULT; if (strncmp(stkbuf, reject_str, strlen(reject_str)) == 0) op = RTAS_REJECT_TMP_IMG; else if (strncmp(stkbuf, commit_str, strlen(commit_str)) == 0) @@ -425,18 +416,11 @@ static ssize_t manage_flash_write(struct file *file, const char __user *buf, } if (op == -1) { /* buf is empty, or contains invalid string */ - rc = -EINVAL; - goto error; + return -EINVAL; } manage_flash(args_buf, op); -out: - mutex_unlock(&rtas_manage_flash_mutex); return count; - -error: - mutex_unlock(&rtas_manage_flash_mutex); - return rc; } /* @@ -499,16 +483,14 @@ static ssize_t validate_flash_write(struct file *file, const char __user *buf, { struct rtas_validate_flash_t *const args_buf = &rtas_validate_flash_data; - int rc; - mutex_lock(&rtas_validate_flash_mutex); + guard(mutex)(&rtas_validate_flash_mutex); /* We are only interested in the first 4K of the * candidate image */ if ((*off >= VALIDATE_BUF_SIZE) || (args_buf->status == VALIDATE_AUTH)) { *off += count; - mutex_unlock(&rtas_validate_flash_mutex); return count; } @@ -519,20 +501,14 @@ static ssize_t validate_flash_write(struct file *file, const char __user *buf, args_buf->status = VALIDATE_INCOMPLETE; } - if (!access_ok(buf, count)) { - rc = -EFAULT; - goto done; - } - if (copy_from_user(args_buf->buf + *off, buf, count)) { - rc = -EFAULT; - goto done; - } + if (!access_ok(buf, count)) + return -EFAULT; + + if (copy_from_user(args_buf->buf + *off, buf, count)) + return -EFAULT; *off += count; - rc = count; -done: - mutex_unlock(&rtas_validate_flash_mutex); - return rc; + return count; } static int validate_flash_release(struct inode *inode, struct file *file) -- 2.39.3
