Skip to contentSkip to conversation

cifs: don't check for failure from mempool_alloc()

PATCH Applied NeilBrown 2 participants 2 messages Apr 10, 2017 – Apr 27, 2017

Subsystems (2)
lore
Share & tools
lore

NeilBrown

author
#0 lore raw

PATCH 1/1 cifs: don't check for failure from mempool_alloc()

mempool_alloc() cannot fail if the gfp flags allow it to sleep, and both GFP_FS allows for sleeping.

So these tests of the return value from mempool_alloc() cannot be needed.

---
 fs/cifs/misc.c          | 14 +++++---------
 fs/cifs/smb2transport.c | 30 +++++++++++++-----------------
 fs/cifs/transport.c     | 32 ++++++++++++++------------------
 3 files changed, 32 insertions(+), 44 deletions(-)
fs/cifs/misc.c +5 -9
index d3fb11529ed9..843787850435 100644
@@ -167,13 +167,11 @@ cifs_buf_get(void)
 
 	/* clear the first few header bytes */
 	/* for most paths, more is cleared in header_assemble */
-	if (ret_buf) {
-		memset(ret_buf, 0, buf_size + 3);
-		atomic_inc(&bufAllocCount);
+	memset(ret_buf, 0, buf_size + 3);
+	atomic_inc(&bufAllocCount);
 #ifdef CONFIG_CIFS_STATS2
-		atomic_inc(&totBufAllocCount);
+	atomic_inc(&totBufAllocCount);
 #endif /* CONFIG_CIFS_STATS2 */
-	}
 
 	return ret_buf;
 }
@@ -201,15 +199,13 @@ cifs_small_buf_get(void)
    albeit slightly larger than necessary and maxbuffersize
    defaults to this and can not be bigger */
 	ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS);
-	if (ret_buf) {
 	/* No need to clear memory here, cleared in header assemble */
 	/*	memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
-		atomic_inc(&smBufAllocCount);
+	atomic_inc(&smBufAllocCount);
 #ifdef CONFIG_CIFS_STATS2
-		atomic_inc(&totSmBufAllocCount);
+	atomic_inc(&totSmBufAllocCount);
 #endif /* CONFIG_CIFS_STATS2 */
 
-	}
 	return ret_buf;
 }
 
fs/cifs/smb2transport.c +13 -17
index 506b67fc93d9..c69ec96e92ac 100644
@@ -538,23 +538,19 @@ smb2_mid_entry_alloc(const struct smb2_sync_hdr *shdr,
 	}
 
 	temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
-	if (temp == NULL)
-		return temp;
-	else {
-		memset(temp, 0, sizeof(struct mid_q_entry));
-		temp->mid = le64_to_cpu(shdr->MessageId);
-		temp->pid = current->pid;
-		temp->command = shdr->Command; /* Always LE */
-		temp->when_alloc = jiffies;
-		temp->server = server;
-
-		/*
-		 * The default is for the mid to be synchronous, so the
-		 * default callback just wakes up the current task.
-		 */
-		temp->callback = cifs_wake_up_task;
-		temp->callback_data = current;
-	}
+	memset(temp, 0, sizeof(struct mid_q_entry));
+	temp->mid = le64_to_cpu(shdr->MessageId);
+	temp->pid = current->pid;
+	temp->command = shdr->Command; /* Always LE */
+	temp->when_alloc = jiffies;
+	temp->server = server;
+
+	/*
+	 * The default is for the mid to be synchronous, so the
+	 * default callback just wakes up the current task.
+	 */
+	temp->callback = cifs_wake_up_task;
+	temp->callback_data = current;
 
 	atomic_inc(&midCount);
 	temp->mid_state = MID_REQUEST_ALLOCATED;
fs/cifs/transport.c +14 -18
index f6e13a977fc8..4d64b5b8fc9c 100644
@@ -55,26 +55,22 @@ AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
 	}
 
 	temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
-	if (temp == NULL)
-		return temp;
-	else {
-		memset(temp, 0, sizeof(struct mid_q_entry));
-		temp->mid = get_mid(smb_buffer);
-		temp->pid = current->pid;
-		temp->command = cpu_to_le16(smb_buffer->Command);
-		cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
+	memset(temp, 0, sizeof(struct mid_q_entry));
+	temp->mid = get_mid(smb_buffer);
+	temp->pid = current->pid;
+	temp->command = cpu_to_le16(smb_buffer->Command);
+	cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
 	/*	do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
-		/* when mid allocated can be before when sent */
-		temp->when_alloc = jiffies;
-		temp->server = server;
+	/* when mid allocated can be before when sent */
+	temp->when_alloc = jiffies;
+	temp->server = server;
 
-		/*
-		 * The default is for the mid to be synchronous, so the
-		 * default callback just wakes up the current task.
-		 */
-		temp->callback = cifs_wake_up_task;
-		temp->callback_data = current;
-	}
+	/*
+	 * The default is for the mid to be synchronous, so the
+	 * default callback just wakes up the current task.
+	 */
+	temp->callback = cifs_wake_up_task;
+	temp->callback_data = current;
 
 	atomic_inc(&midCount);
 	temp->mid_state = MID_REQUEST_ALLOCATED;
Signature · 1 line
2.12.2
Applied
#1 lore raw

merged into cifs-2.6.git for-next

Quoted 142 lines · NeilBrown

mempool_alloc() cannot fail if the gfp flags allow it to sleep, and both GFP_FS allows for sleeping.

So these tests of the return value from mempool_alloc() cannot be needed.

---
 fs/cifs/misc.c          | 14 +++++---------
 fs/cifs/smb2transport.c | 30 +++++++++++++-----------------
 fs/cifs/transport.c     | 32 ++++++++++++++------------------
 3 files changed, 32 insertions(+), 44 deletions(-)
fs/cifs/misc.c +5 -9
index d3fb11529ed9..843787850435 100644
@@ -167,13 +167,11 @@ cifs_buf_get(void)
 
        /* clear the first few header bytes */
        /* for most paths, more is cleared in header_assemble */
-       if (ret_buf) {
-               memset(ret_buf, 0, buf_size + 3);
-               atomic_inc(&bufAllocCount);
+       memset(ret_buf, 0, buf_size + 3);
+       atomic_inc(&bufAllocCount);
 #ifdef CONFIG_CIFS_STATS2
-               atomic_inc(&totBufAllocCount);
+       atomic_inc(&totBufAllocCount);
 #endif /* CONFIG_CIFS_STATS2 */
-       }
 
        return ret_buf;
 }
@@ -201,15 +199,13 @@ cifs_small_buf_get(void)
    albeit slightly larger than necessary and maxbuffersize
    defaults to this and can not be bigger */
        ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS);
-       if (ret_buf) {
        /* No need to clear memory here, cleared in header assemble */
        /*      memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
-               atomic_inc(&smBufAllocCount);
+       atomic_inc(&smBufAllocCount);
 #ifdef CONFIG_CIFS_STATS2
-               atomic_inc(&totSmBufAllocCount);
+       atomic_inc(&totSmBufAllocCount);
 #endif /* CONFIG_CIFS_STATS2 */
 
-       }
        return ret_buf;
 }
 
fs/cifs/smb2transport.c +13 -17
index 506b67fc93d9..c69ec96e92ac 100644
@@ -538,23 +538,19 @@ smb2_mid_entry_alloc(const struct smb2_sync_hdr *shdr,
        }
 
        temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
-       if (temp == NULL)
-               return temp;
-       else {
-               memset(temp, 0, sizeof(struct mid_q_entry));
-               temp->mid = le64_to_cpu(shdr->MessageId);
-               temp->pid = current->pid;
-               temp->command = shdr->Command; /* Always LE */
-               temp->when_alloc = jiffies;
-               temp->server = server;
-
-               /*
-                * The default is for the mid to be synchronous, so the
-                * default callback just wakes up the current task.
-                */
-               temp->callback = cifs_wake_up_task;
-               temp->callback_data = current;
-       }
+       memset(temp, 0, sizeof(struct mid_q_entry));
+       temp->mid = le64_to_cpu(shdr->MessageId);
+       temp->pid = current->pid;
+       temp->command = shdr->Command; /* Always LE */
+       temp->when_alloc = jiffies;
+       temp->server = server;
+
+       /*
+        * The default is for the mid to be synchronous, so the
+        * default callback just wakes up the current task.
+        */
+       temp->callback = cifs_wake_up_task;
+       temp->callback_data = current;
 
        atomic_inc(&midCount);
        temp->mid_state = MID_REQUEST_ALLOCATED;
fs/cifs/transport.c +14 -19
index f6e13a977fc8..4d64b5b8fc9c 100644
@@ -55,26 +55,22 @@ AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
        }
 
        temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
-       if (temp == NULL)
-               return temp;
-       else {
-               memset(temp, 0, sizeof(struct mid_q_entry));
-               temp->mid = get_mid(smb_buffer);
-               temp->pid = current->pid;
-               temp->command = cpu_to_le16(smb_buffer->Command);
-               cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
+       memset(temp, 0, sizeof(struct mid_q_entry));
+       temp->mid = get_mid(smb_buffer);
+       temp->pid = current->pid;
+       temp->command = cpu_to_le16(smb_buffer->Command);
+       cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
        /*      do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
-               /* when mid allocated can be before when sent */
-               temp->when_alloc = jiffies;
-               temp->server = server;
+       /* when mid allocated can be before when sent */
+       temp->when_alloc = jiffies;
+       temp->server = server;
 
-               /*
-                * The default is for the mid to be synchronous, so the
-                * default callback just wakes up the current task.
-                */
-               temp->callback = cifs_wake_up_task;
-               temp->callback_data = current;
-       }
+       /*
+        * The default is for the mid to be synchronous, so the
+        * default callback just wakes up the current task.
+        */
+       temp->callback = cifs_wake_up_task;
+       temp->callback_data = current;
 
        atomic_inc(&midCount);
        temp->mid_state = MID_REQUEST_ALLOCATED;
--

2.12.2

Signature · 3 lines
Thanks,

Steve