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

From: NeilBrown
Date: Sun Apr 09 2017 - 22:09:11 EST



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.

Signed-off-by: NeilBrown <neilb@xxxxxxxx>
---
fs/cifs/misc.c | 14 +++++---------
fs/cifs/smb2transport.c | 30 +++++++++++++-----------------
fs/cifs/transport.c | 32 ++++++++++++++------------------
3 files changed, 32 insertions(+), 44 deletions(-)

diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index d3fb11529ed9..843787850435 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -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;
}

diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
index 506b67fc93d9..c69ec96e92ac 100644
--- a/fs/cifs/smb2transport.c
+++ b/fs/cifs/smb2transport.c
@@ -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;
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index f6e13a977fc8..4d64b5b8fc9c 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -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

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