1 From: Gabor Juhos <juhosg@openwrt.org>
2 Subject: spi-fsl-espi: avoid frequent high order allocations
4 The driver allocates 64KiB of memory fro a local buffer before
5 each transfer and releases that afterwards. When the memory is
6 fragmented this allocation often fails and causes a warning like
9 kworker/u2:2: page allocation failure: order:4, mode:0x10c0d0
10 CPU: 0 PID: 7011 Comm: kworker/u2:2 Not tainted 3.10.24 #1
11 Workqueue: ffe07000.spi mpc8xxx_spi_work
13 [c1c6dcf0] [c0006914] show_stack+0x50/0x170 (unreliable)
14 [c1c6dd30] [c0259858] dump_stack+0x24/0x34
15 [c1c6dd40] [c00672e8] warn_alloc_failed+0x120/0x13c
16 [c1c6dd90] [c0069920] __alloc_pages_nodemask+0x574/0x5c8
17 [c1c6de20] [c0069990] __get_free_pages+0x1c/0x4c
18 [c1c6de30] [c0185174] fsl_espi_do_one_msg+0x128/0x2a0
19 [c1c6de90] [c0184290] mpc8xxx_spi_work+0x50/0x7c
20 [c1c6dea0] [c0037af8] process_one_work+0x208/0x30c
21 [c1c6dec0] [c00387a0] worker_thread+0x20c/0x308
22 [c1c6def0] [c003de60] kthread+0xa4/0xa8
23 [c1c6df40] [c000c4bc] ret_from_kernel_thread+0x5c/0x64
25 m25p80 spi0.0: error -12 reading SR
26 end_request: I/O error, dev mtdblock3, sector 680
27 SQUASHFS error: squashfs_read_data failed to read block 0x54a4a
28 SQUASHFS error: Unable to read data cache entry [54a4a]
30 Preallocate the buffer from the probe routine to avoid
33 Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
35 --- a/drivers/spi/spi-fsl-espi.c
36 +++ b/drivers/spi/spi-fsl-espi.c
37 @@ -338,17 +338,13 @@ static void fsl_espi_do_trans(struct spi
38 static void fsl_espi_cmd_trans(struct spi_message *m,
39 struct fsl_espi_transfer *trans, u8 *rx_buff)
41 + struct spi_device *spi = m->spi;
42 + struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
43 struct spi_transfer *t;
45 + u8 *local_buf = mspi->local_buf;
47 struct fsl_espi_transfer *espi_trans = trans;
49 - local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
51 - espi_trans->status = -ENOMEM;
55 list_for_each_entry(t, &m->transfers, transfer_list) {
57 memcpy(local_buf + i, t->tx_buf, t->len);
58 @@ -361,28 +357,23 @@ static void fsl_espi_cmd_trans(struct sp
59 fsl_espi_do_trans(m, espi_trans);
61 espi_trans->actual_length = espi_trans->len;
65 static void fsl_espi_rw_trans(struct spi_message *m,
66 struct fsl_espi_transfer *trans, u8 *rx_buff)
68 + struct spi_device *spi = m->spi;
69 + struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
70 struct fsl_espi_transfer *espi_trans = trans;
71 unsigned int n_tx = espi_trans->n_tx;
72 unsigned int n_rx = espi_trans->n_rx;
73 struct spi_transfer *t;
75 + u8 *local_buf = mspi->local_buf;
77 unsigned int trans_len;
81 - local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
83 - espi_trans->status = -ENOMEM;
87 for (pos = 0, loop = 0; pos < n_rx; pos += trans_len, loop++) {
88 trans_len = n_rx - pos;
89 if (trans_len > SPCOM_TRANLEN_MAX - n_tx)
90 @@ -416,8 +407,6 @@ static void fsl_espi_rw_trans(struct spi
92 espi_trans->actual_length += espi_trans->len;
98 static void fsl_espi_do_one_msg(struct spi_message *m)
99 @@ -585,6 +574,7 @@ static irqreturn_t fsl_espi_irq(s32 irq,
100 static void fsl_espi_remove(struct mpc8xxx_spi *mspi)
102 iounmap(mspi->reg_base);
103 + kfree(mspi->local_buf);
106 static struct spi_master * fsl_espi_probe(struct device *dev,
107 @@ -615,10 +605,16 @@ static struct spi_master * fsl_espi_prob
108 mpc8xxx_spi->spi_do_one_msg = fsl_espi_do_one_msg;
109 mpc8xxx_spi->spi_remove = fsl_espi_remove;
111 + mpc8xxx_spi->local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
112 + if (!mpc8xxx_spi->local_buf) {
117 mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
118 if (!mpc8xxx_spi->reg_base) {
124 reg_base = mpc8xxx_spi->reg_base;
125 @@ -661,6 +657,8 @@ unreg_master:
126 free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
128 iounmap(mpc8xxx_spi->reg_base);
130 + kfree(mpc8xxx_spi->local_buf);
132 spi_master_put(master);
134 --- a/drivers/spi/spi-fsl-lib.h
135 +++ b/drivers/spi/spi-fsl-lib.h
136 @@ -30,6 +30,7 @@ struct mpc8xxx_spi {
138 #ifdef CONFIG_SPI_FSL_ESPI