Function report

Linux Kernel

v5.5.9

Brick Technologies Co., Ltd

Source Code:block\blk-iocost.c Create Date:2022-07-28 17:49:35
Last Modify:2020-03-12 14:18:49 Copyright©Brick
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Annotation kernel can get tool activityDownload SCCTChinese

Name:ioc_qos_write

Proto:static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input, size_t nbytes, loff_t off)

Type:ssize_t

Parameter:

TypeParameterName
struct kernfs_open_file *of
char *input
size_tnbytes
loff_toff
2192  disk = lkg_conf_prep - parse and prepare for per-blkg config update*@inputp: input string pointer* Parse the device node prefix part, MAJ:MIN, of per-blkg config update* from @input and get and return the matching gendisk. *@inputp is
2193  If IS_ERR(disk) Then Return PTR_ERR(disk)
2196  ioc = q_to_ioc(queue)
2197  If Not ioc Then
2198  ret = blk_iocost_init(queue)
2199  If ret Then Go to err
2201  ioc = q_to_ioc(queue)
2204  spin_lock_irq( & lock)
2205  memcpy(qos, qos, size of qos )
2206  enable = enabled
2207  user = user_qos_params
2208  spin_unlock_irq( & lock)
2210  When p = strsep - Split a string into tokens*@s: The string to be searched*@ct: The characters to search for* strsep() updates @s to point after the token, ready for the next call.* It returns empty tokens, too, behaving exactly like the libc function cycle
2216  If Not p Then Continue
2220  Case match_token: - Find a token (and optional args) in a string*@s: the string to examine for token/argument pairs*@table: match_table_t describing the set of allowed option tokens and the* arguments that may be associated with them. Must be terminated with a == QOS_ENABLE
2221  match_u64: - scan a decimal representation of a u64 from* a substring_t*@s: substring_t to be scanned*@result: resulting unsigned long long on success* Description: Attempts to parse the &substring_t @s as a long decimal* integer
2222  enable = v
2223  Continue
2224  Case match_token: - Find a token (and optional args) in a string*@s: the string to examine for token/argument pairs*@table: match_table_t describing the set of allowed option tokens and the* arguments that may be associated with them. Must be terminated with a == QOS_CTRL
2225  match_strlcpy: - Copy the characters from a substring_t to a sized buffer*@dest: where to copy to*@src: &substring_t to copy*@size: size of destination buffer* Description: Copy the characters in &substring_t @src to the* c-style string @dest
2226  If Not strcmp(buf, "auto") Then user = false
2228  Else if Not strcmp(buf, "user") Then user = true
2230  Else Go to einval
2232  Continue
2235  tok = match_token(p, qos_tokens, args)
2237  Case tok == QOS_RPPM
2238  Case tok == QOS_WPPM
2239  If match_strlcpy: - Copy the characters from a substring_t to a sized buffer*@dest: where to copy to*@src: &substring_t to copy*@size: size of destination buffer* Description: Copy the characters in &substring_t @src to the* c-style string @dest >= size of buf Then Go to einval
2242  If group_parse_float - parse a floating number*@input: input string*@dec_shift: number of decimal digits to shift*@v: output* Parse a decimal floating point number in @input and store the result in*@v with decimal point right shifted @dec_shift times Then Go to einval
2244  If v < 0 || v > 10000 Then Go to einval
2246  qos[tok] = v * 100
2247  Break
2248  Case tok == QOS_RLAT
2249  Case tok == QOS_WLAT
2250  If match_u64: - scan a decimal representation of a u64 from* a substring_t*@s: substring_t to be scanned*@result: resulting unsigned long long on success* Description: Attempts to parse the &substring_t @s as a long decimal* integer Then Go to einval
2252  qos[tok] = v
2253  Break
2254  Case tok == QOS_MIN
2255  Case tok == QOS_MAX
2256  If match_strlcpy: - Copy the characters from a substring_t to a sized buffer*@dest: where to copy to*@src: &substring_t to copy*@size: size of destination buffer* Description: Copy the characters in &substring_t @src to the* c-style string @dest >= size of buf Then Go to einval
2259  If group_parse_float - parse a floating number*@input: input string*@dec_shift: number of decimal digits to shift*@v: output* Parse a decimal floating point number in @input and store the result in*@v with decimal point right shifted @dec_shift times Then Go to einval
2261  If v < 0 Then Go to einval
2263  qos[tok] = clamp_t - return a value clamped to a given range using a given type*@type: the type of variable to use*@val: current value*@lo: minimum allowable value*@hi: maximum allowable value* This macro does no typechecking and uses temporary variables of type(s64, v * 100, VRATE_MIN_PPM, VRATE_MAX_PPM)
2265  Break
2266  Default
2267  Go to einval
2269  user = true
2272  If qos[QOS_MIN] > qos[QOS_MAX] Then Go to einval
2275  spin_lock_irq( & lock)
2277  If enable Then
2278  lk_queue_flag_set - atomically set a queue flag*@flag: flag to be set*@q: request queue
2279  enabled = true
2280  Else
2281  lk_queue_flag_clear - atomically clear a queue flag*@flag: flag to be cleared*@q: request queue
2282  enabled = false
2285  If user Then
2286  memcpy(qos, qos, size of qos )
2287  user_qos_params = true
2288  Else
2289  user_qos_params = false
2292  ioc_refresh_params(ioc, true)
2293  spin_unlock_irq( & lock)
2295  This is a counterpart of get_disk_and_module() and thus also of* get_gendisk().
2296  Return nbytes
2297  einval :
2298  ret = -EINVAL
2299  err :
2300  This is a counterpart of get_disk_and_module() and thus also of* get_gendisk().
2301  Return ret